chore(web): remove darkMode: 'class' from tailwind config — Phase 7 retired

Operator decision 2026-05-14: "no dark mode and no future dark mode wiring to maintain." The originally-optional Phase 7 (the rebuild path that would have superseded Phase 0's rip-out if customer signal materialized) is formally retired in the frontend-design-audit.html banner stack + Phase 7 H3 header. Phase 0's closure rationale ("leave `darkMode: 'class'` in tailwind config for the eventual Phase 7 rebuild") is now superseded — keeping that line set would resurface as the same half-wired-hook pattern that drove the original FE-H1 finding, just at the config layer instead of the HTML layer. Phase 0 removed `class="dark"` from <html> + the body `bg-slate-900`; this commit closes the loop by also removing the tailwind config option that pointed at a future feature that won't arrive. If the decision ever reverses, this line restores in a one-diff revert + a full re-audit of every primitive and page for `dark:` variants (see the retired Phase 7 executable prompt for the rules: ship complete or not at all; piecemeal dark-mode is exactly the original finding). Verification: • npx tsc --noEmit — exits 0 • npx vite build — ✓ built in 3.20s (Tailwind doesn't need darkMode set to compile; output is identical because there are zero `dark:` classes in src/ to gate behind anything) • Audit HTML (workspace-only, not repo-tracked) updated with: - Phase 7 RETIRED banner at top of banner stack (amber accent) - Phase 7 H3 header flipped to "✗ Retired 2026-05-14" - FE-H1 row note extended with the lock-in decision - Phase 0's "Do NOT delete darkMode: 'class'" guidance struck through + marked SUPERSEDED with a pointer to the new banner
feat(frontend): Phase 6 Locale + Date/Time Discipline — close I18N-H1 + I18N-H2 + I18N-H3 + I18N-M2
2026-06-08 07:59:06 +00:00 · 2026-05-14 17:16:40 +00:00 · 2026-05-14 17:10:19 +00:00 · 2026-05-14 16:52:19 +00:00 · 2026-05-14 16:44:37 +00:00 · 2026-05-14 16:17:48 +00:00
114 changed files with 10880 additions and 1755 deletions
@@ -132,6 +132,18 @@ jobs:
        run: |
          go test ./internal/service/... ./internal/api/handler/... ./internal/api/middleware/... ./internal/api/router/... ./internal/auth/... ./internal/integration/... ./internal/connector/issuer/... ./internal/connector/target/... ./internal/connector/notifier/... ./internal/connector/discovery/... ./internal/crypto/... ./internal/mcp/... ./internal/cli/... ./internal/domain/... ./internal/validation/... ./internal/tlsprobe/... ./internal/ciparity/... -count=1 -cover -coverprofile=coverage.out

+      - name: Multi-replica rate-limit integration test (Phase 13 Sprint 13.2/13.3 — ARCH-M1 closure proof)
+        # The falsifiable proof that CERTCTL_RATE_LIMIT_BACKEND=postgres
+        # enforces caps cluster-wide. testcontainers-go spins one
+        # Postgres container; 3 *PostgresSlidingWindowLimiter instances
+        # share it; 100 concurrent Allow("test-key") with cap=10 must
+        # see exactly 10 succeed + 90 ErrRateLimited. Failure here =
+        # the row-lock arbitration broke; ARCH-M1 closure is invalid.
+        run: |
+          go test -tags=integration -race -count=1 -timeout=300s \
+              -run TestRateLimit_PostgresBackend_CapEnforcedAcrossReplicas \
+              ./internal/integration/...
+
      - name: Check Coverage Thresholds
        # ci-pipeline-cleanup Phase 2: per-package floors moved to
        # .github/coverage-thresholds.yml. Each entry has `floor:` +
@@ -92,10 +92,12 @@ Security: three authentication paths — API keys (SHA-256 hashed + constant-tim
 ```bash
 git clone https://github.com/certctl-io/certctl.git
 cd certctl
-docker compose -f deploy/docker-compose.yml -f deploy/docker-compose.demo.yml up -d --build
+./deploy/demo-up.sh -d --build
 ```

-Wait ~30 seconds, then open **https://localhost:8443** in your browser. The demo overlay flips the base into demo-mode auth (every request served as the synthetic admin actor `actor-demo-anon` — the server emits a prominent ⚠ DEMO MODE banner at boot reminding you this posture is for evaluation only) and seeds 180 days of realistic history across 13 issuers, 8 agents, managed + discovered certs, jobs, deploys, audit, and notification events. The `certctl-tls-init` init container self-signs an ECDSA-P256 cert on first boot — accept the browser warning for the demo, or feed the generated `ca.crt` to your client.
+Wait ~30 seconds, then open **https://localhost:8443** in your browser. The `demo-up.sh` wrapper exports a fresh `CERTCTL_DEMO_MODE_ACK_TS=$(date +%s)` and forwards the remaining args to `docker compose -f docker-compose.yml -f docker-compose.demo.yml up`. The timestamp export is required by the Phase 2 SEC-H3 fail-closed guard in `internal/config/config.go::Validate` — demo deploys must re-ACK every 24h so a forgotten demo container never silently ends up serving production traffic with `auth-type=none`. The bare `docker compose ... up` command without the timestamp refuses to boot; the wrapper script is the supported entry point.
+
+The demo overlay flips the base into demo-mode auth (every request served as the synthetic admin actor `actor-demo-anon` — the server emits a prominent ⚠ DEMO MODE banner at boot reminding you this posture is for evaluation only) and seeds 180 days of realistic history across 13 issuers, 8 agents, managed + discovered certs, jobs, deploys, audit, and notification events. The `certctl-tls-init` init container self-signs an ECDSA-P256 cert on first boot — accept the browser warning for the demo, or feed the generated `ca.crt` to your client.

 **Production path — `.env` required, fail-closed on placeholders:**

@@ -0,0 +1 @@
+0
@@ -1,48 +1,100 @@
 # Routes registered in internal/api/router/router.go that are intentionally
-# NOT in api/openapi.yaml. Each entry needs a one-line `why:` justification.
+# NOT in api/openapi.yaml. Each entry needs a one-line `why:` justification
+# AND a required `category:` field (added in Phase 13 Sprint 13.1,
+# 2026-05-14, architecture diligence audit ARCH-H1).
+#
 # Adding a new entry requires PR-time review.
 #
 # OpenAPI-shaped REST endpoints belong in api/openapi.yaml, NOT here.
-# This list is for protocol-shaped (SCEP wire endpoints) and operational
-# (health, metrics, pprof) routes only.
+# This list is for protocol-shaped (SCEP/ACME/EST wire endpoints) and
+# operational (health, metrics, pprof) routes only.
 #
 # Per ci-pipeline-cleanup bundle Phase 9 / frozen decision 0.11.
 #
-# Phase 5 reconciliation (2026-05-13, architecture diligence audit
-# ARCH-H1): of the 64 entries below, 35 are legitimate wire-protocol
-# carve-outs (SCEP RFC 8894 = 8 entries, ACME RFC 8555 default + per-
-# profile = 27 entries) that MUST stay. The remaining 29 are REST-
-# shaped routes whose OpenAPI ops were deferred during their original
-# Bundle 2 / audit-2026-05-10 / 2026-05-11 work. Burn-down plan:
+# ──────────────────────────────────────────────────────────────────────
+# The two-bucket contract (Phase 13 Sprint 13.1)
+# ──────────────────────────────────────────────────────────────────────
 #
-#   Sprint A (per-cluster, ~7-8 ops each):
-#     Cluster 1: auth/sessions + auth/oidc (12 ops)
-#     Cluster 2: auth/breakglass + auth/users + auth/runtime-config (8 ops)
-#     Cluster 3: audit/export + demo-residual/cleanup + auth/logout +
-#                auth/breakglass/login + auth/oidc/{login,callback,bcl} (9 ops)
+#   category: wire-protocol
+#     The route's wire shape is dictated by an IETF RFC (SCEP RFC 8894,
+#     ACME RFC 8555, ACME ARI RFC 9773, EST RFC 7030) or it's a
+#     sibling/shorthand variant of such a route (same wire semantics,
+#     different cosmetic path — e.g. trailing-slash forms, default-
+#     profile shorthands). Documenting these as REST operations in
+#     openapi.yaml would duplicate the RFC with no information gain;
+#     the canonical operator references live in docs/acme-server.md +
+#     docs/operator/scep.md + docs/operator/est.md. These entries
+#     NEVER burn down — they're protocol contracts, not gaps.
+#
+#   category: rest-deferred
+#     The route is REST-shaped (resource CRUD, JSON request/response,
+#     RBAC-gated) but its OpenAPI operation was deferred when the
+#     handler shipped. These MUST monotonically decrease to zero.
+#     Phase 13 Sprints 13.4-13.6 author the OpenAPI ops + delete the
+#     corresponding exception entries; the
+#     openapi-rest-deferred-monotonic.sh CI guard fails any PR that
+#     grows the rest-deferred bucket vs the checked-in baseline at
+#     api/openapi-handler-exceptions-baseline.txt.
+#
+# ──────────────────────────────────────────────────────────────────────
+# Phase 13 Sprint 13.1 categorization (2026-05-14)
+# ──────────────────────────────────────────────────────────────────────
+#
+# Current split, re-derived by the parity script's bucket-reporting
+# subcommand (post-Sprint-13.6 / 2026-05-14):
+#
+#   total entries:           36
+#   wire-protocol:           36
+#   rest-deferred:           0    ← THE FLOOR — ARCH-H1 substantive close
+#
+# Burn-down progress:
+#
+#   Sprint 13.4 SHIPPED — 28 - 13 = 15 (auth/sessions cluster 3 ops +
+#                               auth/oidc CRUD + JWKS + test + refresh
+#                               + group-mappings cluster, 10 ops)
+#   Sprint 13.5 SHIPPED — 15 -  8 =  7 (auth/breakglass admin 4 ops +
+#                               auth/users 3 ops + auth/runtime-config
+#                               1 op, 8 ops total)
+#   Sprint 13.6 SHIPPED —  7 -  7 =  0 (audit/export 1 op + demo-
+#                               residual/cleanup 1 op + auth/logout 1 op +
+#                               auth/breakglass/login 1 op + 3 OIDC
+#                               browser-flow endpoints, 7 ops total)
+#
+# Sprint 13.7 next tightens the parity-script's rest-deferred floor
+# from monotonic-decrease to a hard zero-exact pin. After that, any
+# new REST route MUST land with an OpenAPI op or fail CI — no escape
+# hatch via `category: rest-deferred`.
 #
 # Each authored OpenAPI op needs request/response schemas (not
 # placeholders) so the generated client at web/orval.config.ts emits
 # typed signatures. When an op lands, delete the corresponding entry
-# below + bump the openapi-handler-parity.sh expected counts.
+# below + bump api/openapi-handler-exceptions-baseline.txt downward.

 documented_exceptions:
  - route: "GET /scep"
    why: "SCEP wire-protocol endpoint per RFC 8894 §3.1; serves CA certs via GetCACert/GetCACaps query params, NOT a REST resource."
+    category: wire-protocol
  - route: "POST /scep"
    why: "SCEP wire-protocol endpoint per RFC 8894 §3.1; receives PKCSReq / RenewalReq PKIMessages, NOT a REST resource."
+    category: wire-protocol
  - route: "GET /scep/"
    why: "SCEP wire-protocol endpoint with trailing-slash variant; ChromeOS clients send the trailing-slash form."
+    category: wire-protocol
  - route: "POST /scep/"
    why: "SCEP wire-protocol endpoint with trailing-slash variant; ChromeOS clients send the trailing-slash form."
+    category: wire-protocol
  - route: "GET /scep-mtls"
    why: "SCEP-mTLS sibling endpoint per ci-pipeline-cleanup-prerequisite EST RFC 7030 hardening Phase 6.5; same wire-protocol semantics, mutually-authenticated TLS variant."
+    category: wire-protocol
  - route: "POST /scep-mtls"
    why: "SCEP-mTLS sibling endpoint, POST variant."
+    category: wire-protocol
  - route: "GET /scep-mtls/"
    why: "SCEP-mTLS sibling endpoint, trailing-slash variant."
+    category: wire-protocol
  - route: "POST /scep-mtls/"
    why: "SCEP-mTLS sibling endpoint, trailing-slash POST variant."
+    category: wire-protocol

  # ACME server (RFC 8555 + RFC 9773 ARI) — wire-protocol surface.
  # Like SCEP/EST, ACME is a JWS-signed-JSON wire protocol whose
@@ -54,62 +106,90 @@ documented_exceptions:
  # challenge, cert, key-change, revoke-cert, renewal-info routes land.
  - route: "GET /acme/profile/{id}/directory"
    why: "ACME server RFC 8555 §7.1.1 directory; documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "HEAD /acme/profile/{id}/new-nonce"
    why: "ACME server RFC 8555 §7.2 new-nonce; documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "GET /acme/profile/{id}/new-nonce"
    why: "ACME server RFC 8555 §7.2 new-nonce GET form; documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "POST /acme/profile/{id}/new-account"
    why: "ACME server RFC 8555 §7.3 new-account (JWS jwk); documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "POST /acme/profile/{id}/account/{acc_id}"
    why: "ACME server RFC 8555 §7.3.2 + §7.3.6 (JWS kid) account update + deactivation; documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "GET /acme/directory"
    why: "ACME server default-profile shorthand; mirrors per-profile when CERTCTL_ACME_SERVER_DEFAULT_PROFILE_ID is set."
+    category: wire-protocol
  - route: "HEAD /acme/new-nonce"
    why: "ACME server default-profile shorthand for new-nonce HEAD."
+    category: wire-protocol
  - route: "GET /acme/new-nonce"
    why: "ACME server default-profile shorthand for new-nonce GET."
+    category: wire-protocol
  - route: "POST /acme/new-account"
    why: "ACME server default-profile shorthand for new-account."
+    category: wire-protocol
  - route: "POST /acme/account/{acc_id}"
    why: "ACME server default-profile shorthand for account update + deactivation."
+    category: wire-protocol

  # Phase 2 — orders + finalize + authz + cert.
  - route: "POST /acme/profile/{id}/new-order"
    why: "ACME server RFC 8555 §7.4 new-order; documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "POST /acme/profile/{id}/order/{ord_id}"
    why: "ACME server RFC 8555 §7.4 order POST-as-GET; documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "POST /acme/profile/{id}/order/{ord_id}/finalize"
    why: "ACME server RFC 8555 §7.4 finalize; documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "POST /acme/profile/{id}/authz/{authz_id}"
    why: "ACME server RFC 8555 §7.5 authz POST-as-GET; documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "POST /acme/profile/{id}/challenge/{chall_id}"
    why: "ACME server RFC 8555 §7.5.1 challenge response; dispatches to Phase 3 validator pool."
+    category: wire-protocol
  - route: "POST /acme/profile/{id}/cert/{cert_id}"
    why: "ACME server RFC 8555 §7.4.2 cert download; documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "POST /acme/new-order"
    why: "Phase 2 default-profile shorthand for new-order."
+    category: wire-protocol
  - route: "POST /acme/order/{ord_id}"
    why: "Phase 2 default-profile shorthand for order POST-as-GET."
+    category: wire-protocol
  - route: "POST /acme/order/{ord_id}/finalize"
    why: "Phase 2 default-profile shorthand for finalize."
+    category: wire-protocol
  - route: "POST /acme/authz/{authz_id}"
    why: "Phase 2 default-profile shorthand for authz POST-as-GET."
+    category: wire-protocol
  - route: "POST /acme/challenge/{chall_id}"
    why: "Phase 3 default-profile shorthand for challenge response."
+    category: wire-protocol
  - route: "POST /acme/cert/{cert_id}"
    why: "Phase 2 default-profile shorthand for cert download."
+    category: wire-protocol
  - route: "POST /acme/profile/{id}/key-change"
    why: "ACME server RFC 8555 §7.3.5 doubly-signed key rollover; documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "POST /acme/profile/{id}/revoke-cert"
    why: "ACME server RFC 8555 §7.6 revoke-cert (kid OR cert-key auth); documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "GET /acme/profile/{id}/renewal-info/{cert_id}"
    why: "ACME server RFC 9773 ACME Renewal Information (unauthenticated GET); documented in docs/acme-server.md."
+    category: wire-protocol
  - route: "POST /acme/key-change"
    why: "Phase 4 default-profile shorthand for key rollover."
+    category: wire-protocol
  - route: "POST /acme/revoke-cert"
    why: "Phase 4 default-profile shorthand for revoke-cert."
+    category: wire-protocol
  - route: "GET /acme/renewal-info/{cert_id}"
    why: "Phase 4 default-profile shorthand for ARI."
+    category: wire-protocol

  # =============================================================================
  # Auth Bundle 2 + audit-2026-05-10/11 fix bundle — REST endpoints not yet
@@ -119,59 +199,3 @@ documented_exceptions:
  # stays green for the v2.1.0 release tag. Threat model + handler contracts
  # live in docs/operator/{rbac.md,auth-threat-model.md,oidc-runbooks/*}.
  # =============================================================================
-  - route: "GET /auth/oidc/login"
-    why: "Bundle 2 Phase 5 OIDC login redirect; user-facing 302 with state cookie. OpenAPI rep deferred to pre-2.2.0."
-  - route: "GET /auth/oidc/callback"
-    why: "Bundle 2 Phase 5 OIDC callback handler; RFC 9700 §4.7.1 + RFC 9207. OpenAPI rep deferred to pre-2.2.0."
-  - route: "POST /auth/logout"
-    why: "Bundle 2 Phase 5 cookie + CSRF revoker. OpenAPI rep deferred to pre-2.2.0."
-  - route: "POST /auth/breakglass/login"
-    why: "Bundle 2 Phase 7.5 public break-glass login (auth-bypass, 404 when disabled). OpenAPI rep deferred to pre-2.2.0."
-  - route: "POST /auth/oidc/back-channel-logout"
-    why: "Bundle 2 Phase 5 RFC OIDC Back-Channel Logout 1.0 endpoint. OpenAPI rep deferred to pre-2.2.0."
-  - route: "GET /api/v1/auth/sessions"
-    why: "Bundle 2 Phase 5 self/admin session list. OpenAPI rep deferred to pre-2.2.0."
-  - route: "DELETE /api/v1/auth/sessions/{id}"
-    why: "Bundle 2 Phase 5 session revoke. OpenAPI rep deferred to pre-2.2.0."
-  - route: "DELETE /api/v1/auth/sessions"
-    why: "Bundle 2 audit-2026-05-10 MED-2/3 revoke-all-except-current."
-  - route: "GET /api/v1/auth/oidc/providers"
-    why: "Bundle 2 Phase 5 OIDC provider CRUD (list)."
-  - route: "POST /api/v1/auth/oidc/providers"
-    why: "Bundle 2 Phase 5 OIDC provider CRUD (create)."
-  - route: "PUT /api/v1/auth/oidc/providers/{id}"
-    why: "Bundle 2 Phase 5 OIDC provider CRUD (update)."
-  - route: "DELETE /api/v1/auth/oidc/providers/{id}"
-    why: "Bundle 2 Phase 5 OIDC provider CRUD (delete)."
-  - route: "POST /api/v1/auth/oidc/providers/{id}/refresh"
-    why: "Bundle 2 audit-2026-05-10 MED-7 JWKS hot-refresh."
-  - route: "GET /api/v1/auth/oidc/providers/{id}/jwks-status"
-    why: "Bundle 2 audit-2026-05-10 MED-7 JWKS health snapshot."
-  - route: "POST /api/v1/auth/oidc/test"
-    why: "Bundle 2 audit-2026-05-10 MED-5 dry-run discovery + JWKS + alg-downgrade check."
-  - route: "GET /api/v1/auth/oidc/group-mappings"
-    why: "Bundle 2 Phase 5 group-mapping CRUD (list)."
-  - route: "POST /api/v1/auth/oidc/group-mappings"
-    why: "Bundle 2 Phase 5 group-mapping CRUD (create)."
-  - route: "DELETE /api/v1/auth/oidc/group-mappings/{id}"
-    why: "Bundle 2 Phase 5 group-mapping CRUD (delete)."
-  - route: "GET /api/v1/auth/breakglass/credentials"
-    why: "Bundle 2 Phase 7.5 admin break-glass list (404 when disabled; password hash never on wire)."
-  - route: "POST /api/v1/auth/breakglass/credentials"
-    why: "Bundle 2 Phase 7.5 admin break-glass set/rotate password."
-  - route: "POST /api/v1/auth/breakglass/credentials/{actor_id}/unlock"
-    why: "Bundle 2 Phase 7.5 admin break-glass unlock after lockout."
-  - route: "DELETE /api/v1/auth/breakglass/credentials/{actor_id}"
-    why: "Bundle 2 Phase 7.5 admin break-glass credential delete."
-  - route: "GET /api/v1/auth/users"
-    why: "Bundle 2 audit-2026-05-10 MED-11 users page."
-  - route: "DELETE /api/v1/auth/users/{id}"
-    why: "Bundle 2 audit-2026-05-10 MED-11 user deactivate."
-  - route: "POST /api/v1/auth/users/{id}/reactivate"
-    why: "Bundle 2 audit-2026-05-10 MED-11 user reactivate."
-  - route: "GET /api/v1/auth/runtime-config"
-    why: "Bundle 2 audit-2026-05-10 MED-12 effective auth-runtime-config (read-only)."
-  - route: "POST /api/v1/auth/demo-residual/cleanup"
-    why: "Audit 2026-05-11 A-8 demo-mode residual-grants cleanup endpoint."
-  - route: "GET /api/v1/audit/export"
-    why: "Bundle 1 Phase 8 streaming NDJSON audit export."
@@ -577,7 +577,7 @@ func main() {
 	// AuthExemptRouterRoutes path. The service-layer Argon2id lockout
 	// state machine remains the second line of defense.
 	breakglassHandler.SetLoginRateLimiter(
-		ratelimit.NewSlidingWindowLimiter(5, time.Minute, 50_000),
+		ratelimit.NewLimiter(cfg.RateLimit.SlidingWindowBackend, db, 5, time.Minute, 50_000),
 	)
 	if cfg.Auth.Breakglass.Enabled {
 		logger.Warn("CERTCTL_BREAKGLASS_ENABLED=true — break-glass admin path is ACTIVE; this bypasses SSO. Disable in steady-state.",
@@ -1000,7 +1000,7 @@ func main() {
 	// Production hardening II Phase 3: per-source-IP OCSP rate limit.
 	// Window 1m so the cap counts requests per minute. Map cap 50k
 	// matches the SCEP/Intune replay cache cap. Zero disables.
-	ocspLimiter := ratelimit.NewSlidingWindowLimiter(cfg.Scheduler.OCSPRateLimitPerIPMin, time.Minute, 50_000)
+	ocspLimiter := ratelimit.NewLimiter(cfg.RateLimit.SlidingWindowBackend, db, cfg.Scheduler.OCSPRateLimitPerIPMin, time.Minute, 50_000)
 	certificateHandler.SetOCSPRateLimiter(ocspLimiter)
 	issuerHandler := handler.NewIssuerHandler(issuerService)
 	targetHandler := handler.NewTargetHandler(targetService)
@@ -1065,7 +1065,7 @@ func main() {
 	exportHandler := handler.NewExportHandler(exportService)
 	// Production hardening II Phase 3: per-actor cert-export rate limit.
 	// Window 1h so the cap counts exports per hour. Zero disables.
-	exportLimiter := ratelimit.NewSlidingWindowLimiter(cfg.Scheduler.CertExportRateLimitPerActorHr, time.Hour, 50_000)
+	exportLimiter := ratelimit.NewLimiter(cfg.RateLimit.SlidingWindowBackend, db, cfg.Scheduler.CertExportRateLimitPerActorHr, time.Hour, 50_000)
 	exportHandler.SetExportRateLimiter(exportLimiter)

 	bulkRevocationHandler := handler.NewBulkRevocationHandler(bulkRevocationService)
@@ -1209,6 +1209,29 @@ func main() {
 	sched.SetSessionGarbageCollector(sessionService)
 	sched.SetBCLReplayGarbageCollector(bclReplayRepo) // Audit 2026-05-10 HIGH-3.
 	sched.SetSessionGCInterval(cfg.Auth.Session.GCInterval)
+
+	// Phase 13 Sprint 13.3 closure (ARCH-M1): when the operator selected
+	// CERTCTL_RATE_LIMIT_BACKEND=postgres, wire the bucket janitor so
+	// stale rows from rate_limit_buckets get swept on the configured
+	// interval. The in-memory backend's prune-on-Allow path keeps
+	// buckets short-lived without a separate sweep, so we skip the
+	// loop entirely for backend=memory.
+	//
+	// maxWindow = 24h: the EST per-principal limiter is the longest
+	// window any current caller configures (the breakglass / OCSP /
+	// export / EST failed-basic limiters use shorter windows). Bump
+	// this if a new caller introduces a longer window — rows pruned
+	// inside their window aren't deletable.
+	if cfg.RateLimit.SlidingWindowBackend == "postgres" {
+		rateLimitGC := ratelimit.NewPostgresGC(db, 24*time.Hour)
+		sched.SetRateLimitGarbageCollector(rateLimitGC)
+		sched.SetRateLimitGCInterval(cfg.RateLimit.SlidingWindowJanitorInterval)
+		logger.Info("rate-limit GC sweep enabled (postgres backend)",
+			"interval", cfg.RateLimit.SlidingWindowJanitorInterval.String(),
+			"max_window", "24h")
+	} else {
+		logger.Info("rate-limit backend = memory; postgres GC sweep not wired (in-memory backend self-prunes)")
+	}
 	logger.Info("session GC sweep enabled",
 		"interval", cfg.Auth.Session.GCInterval.String(),
 		"absolute_timeout", cfg.Auth.Session.AbsoluteTimeout.String(),
@@ -1532,7 +1555,7 @@ func main() {
 				// release. The shared SlidingWindowLimiter applies the same
 				// math the SCEP/Intune limiter uses — extracted in Phase 4.1
 				// of this bundle so both call sites share the implementation.
-				failed := ratelimit.NewSlidingWindowLimiter(10, time.Hour, 50_000)
+				failed := ratelimit.NewLimiter(cfg.RateLimit.SlidingWindowBackend, db, 10, time.Hour, 50_000)
 				estHandler.SetSourceIPRateLimiter(failed)
 			}
 			// Phase 2.1: mTLS sibling route. When MTLSEnabled=true, build a
@@ -1588,7 +1611,7 @@ func main() {
 				mtlsHandler.SetChannelBindingRequired(profile.ChannelBindingRequired)
 				mtlsHandler.SetServerKeygenEnabled(profile.ServerKeygenEnabled)
 				if profile.RateLimitPerPrincipal24h > 0 {
-					perPrincipal := ratelimit.NewSlidingWindowLimiter(profile.RateLimitPerPrincipal24h, 24*time.Hour, 100_000)
+					perPrincipal := ratelimit.NewLimiter(cfg.RateLimit.SlidingWindowBackend, db, profile.RateLimitPerPrincipal24h, 24*time.Hour, 100_000)
 					mtlsHandler.SetPerPrincipalRateLimiter(perPrincipal)
 				}
 				estMTLSHandlers[profile.PathID] = mtlsHandler
@@ -1610,7 +1633,7 @@ func main() {
 			// when configured). The mTLS handler above gets its own
 			// limiter instance so the two routes don't share a bucket.
 			if profile.RateLimitPerPrincipal24h > 0 {
-				perPrincipal := ratelimit.NewSlidingWindowLimiter(profile.RateLimitPerPrincipal24h, 24*time.Hour, 100_000)
+				perPrincipal := ratelimit.NewLimiter(cfg.RateLimit.SlidingWindowBackend, db, profile.RateLimitPerPrincipal24h, 24*time.Hour, 100_000)
 				estHandler.SetPerPrincipalRateLimiter(perPrincipal)
 			}
 			estHandlers[profile.PathID] = estHandler
@@ -12,6 +12,8 @@ data:
  keygen-mode: {{ .Values.server.keygen.mode | quote }}
  rate-limit-rps: {{ .Values.server.rateLimiting.rps | quote }}
  rate-limit-burst: {{ .Values.server.rateLimiting.burst | quote }}
+  rate-limit-backend: {{ .Values.server.rateLimiting.backend | default "memory" | quote }}
+  rate-limit-janitor-interval: {{ .Values.server.rateLimiting.janitorInterval | default "5m" | quote }}
  {{- if .Values.server.cors.origins }}
  cors-origins: {{ .Values.server.cors.origins | quote }}
  {{- end }}
@@ -108,6 +108,19 @@ spec:
                configMapKeyRef:
                  name: {{ include "certctl.fullname" . }}-server
                  key: rate-limit-burst
+            # Phase 13 Sprint 13.3 (ARCH-M1) — cross-replica-consistent
+            # sliding-window rate limiter. Default memory; flip to
+            # postgres when server.replicas > 1.
+            - name: CERTCTL_RATE_LIMIT_BACKEND
+              valueFrom:
+                configMapKeyRef:
+                  name: {{ include "certctl.fullname" . }}-server
+                  key: rate-limit-backend
+            - name: CERTCTL_RATE_LIMIT_JANITOR_INTERVAL
+              valueFrom:
+                configMapKeyRef:
+                  name: {{ include "certctl.fullname" . }}-server
+                  key: rate-limit-janitor-interval
            {{- if .Values.server.cors.origins }}
            - name: CERTCTL_CORS_ORIGINS
              valueFrom:
@@ -211,8 +211,25 @@ server:

  # Rate limiting configuration
  rateLimiting:
-    rps: 100      # Requests per second
-    burst: 200    # Burst capacity
+    rps: 100      # Requests per second (token-bucket middleware)
+    burst: 200    # Burst capacity (token-bucket middleware)
+
+    # Sliding-window-log rate-limit backend (Phase 13 Sprint 13.2/13.3
+    # ARCH-M1 closure). Selects the implementation backing the
+    # break-glass / OCSP / cert-export / EST limiters. See
+    # docs/operator/observability.md for the operator decision tree.
+    #
+    #   memory   — per-process (default; single-replica deploys).
+    #   postgres — cross-replica-consistent via rate_limit_buckets.
+    #              REQUIRED when server.replicas > 1 for accurate
+    #              cluster-wide enforcement.
+    backend: memory
+
+    # Scheduler janitor interval for the postgres backend's
+    # rate_limit_buckets sweep. Ignored when backend=memory (the
+    # in-memory backend self-prunes on every Allow call).
+    # Default 5m; minimum 1m.
+    janitorInterval: "5m"

  # Network scanning configuration
  networkScan:
@@ -121,52 +121,142 @@ explicitly scrubs the password before it reaches the audit subsystem
 (see [`docs/operator/auth-threat-model.md`](auth-threat-model.md) §
 "Break-glass token leak").

-## Rate-limit behavior under restarts and replicas
+## Rate-limit behavior — configurable backend (memory or postgres)

-Where rate limits exist, they are **per-process, in-memory,
-reset-on-restart, and not shared across replicas**. This matters for
-multi-replica deployments and for any compliance posture that asks
-"what limits apply globally vs per-pod."
+The sliding-window-log rate limiters used across certctl's
+authenticated-but-shared-credential code paths (break-glass login,
+OCSP per-IP, cert-export per-actor, EST per-principal, EST
+failed-basic source-IP) carry a **configurable backend**. The
+operator picks between two implementations via
+`CERTCTL_RATE_LIMIT_BACKEND`:
+
+| Value      | When to use                                          |
+|------------|------------------------------------------------------|
+| `memory`   | Default. Single-replica deploys; sketchpad / dev.    |
+| `postgres` | HA deploys (`server.replicas > 1`). Cross-replica-consistent. |
+
+Phase 13 Sprint 13.2/13.3 (architecture diligence audit ARCH-M1
+closure) replaced the prior single-process limitation with a
+substantive close: when the operator opts into `postgres`, all
+replicas share the same
+`rate_limit_buckets` table (migration 000046) and per-key access is
+arbitrated via `SELECT FOR UPDATE` row locks. A 3-replica cluster
+hitting one rate-limited endpoint concurrently sees exactly the
+configured cap succeed across the cluster — not 3× the cap as the
+old per-process backend would have allowed.
+
+### Operator decision tree
+
+```
+Single replica (server.replicas = 1, the helm chart default)?
+  └─ Use CERTCTL_RATE_LIMIT_BACKEND=memory (the default; no action
+     required). Bucket lookups stay in-process; zero DB round-trips
+     on the hot path.
+
+Two or more replicas?
+  └─ Use CERTCTL_RATE_LIMIT_BACKEND=postgres. Two extra DB round-trips
+     per Allow call (BEGIN ... SELECT FOR UPDATE ... UPDATE ... COMMIT);
+     acceptable on the gated hot path. The Sprint 13.2 multi-replica
+     integration test pins exactly-cap enforcement across N replicas
+     as the closure proof.
+```

 ### Inventory

-| Limiter                                              | Scope                | Window | Cap                            | Survives restart? | Shared across replicas? |
-|---|---|---|---|---|---|
-| Break-glass login (per source-IP)                    | `internal/api/handler/auth_breakglass.go` | 60s   | 5 attempts                     | No                | No                      |
-| SCEP/Intune per-device challenge                     | `internal/scep/intune/`                   | 60s   | configurable (`*_PER_MINUTE`)  | No                | No                      |
-| EST per-principal CSR enrollment                     | `internal/est/`                           | 60s   | configurable                   | No                | No                      |
-| EST HTTP-Basic source-IP failed-auth                 | `internal/est/`                           | 60s   | configurable                   | No                | No                      |
-| ACME per-account orders / key-change / challenge-respond | `internal/service/acme.go`            | 1h    | configurable                   | No                | No                      |
+| Limiter                                              | Scope                | Window | Cap                            |
+|---|---|---|---|
+| Break-glass login (per source-IP)                    | `internal/api/handler/auth_breakglass.go` | 60s   | 5 attempts                     |
+| OCSP query (per source-IP)                           | `internal/api/handler/certificates.go`    | 60s   | configurable (`CERTCTL_OCSP_RATE_LIMIT_PER_IP_MIN`) |
+| Cert export (per actor)                              | `internal/api/handler/export.go`          | 1h    | configurable (`CERTCTL_CERT_EXPORT_RATE_LIMIT_PER_ACTOR_HR`) |
+| EST per-principal CSR enrollment                     | `internal/api/handler/est.go`             | 24h   | configurable (per-profile `RateLimitPerPrincipal24h`) |
+| EST HTTP-Basic source-IP failed-auth                 | `internal/api/handler/est.go`             | 60m   | 10 attempts                    |
+| SCEP/Intune per-device challenge                     | `internal/scep/intune/`                   | 60s   | configurable (`*_PER_MINUTE`)  |
+| ACME per-account orders / key-change / challenge-respond | `internal/service/acme.go`            | 1h    | configurable                   |

-All five use the shared `internal/ratelimit/sliding_window.go`
-primitive. Buckets live in a single per-process map guarded by a
-mutex; the package-level cap prevents unbounded growth under
-adversarial key cardinality (default 100,000 keys; oldest-by-newest-
-timestamp evicted under pressure).
+The `CERTCTL_RATE_LIMIT_BACKEND` selector applies to the first five
+(the cmd/server-wired limiters). The SCEP/Intune wrapper + the ACME
+per-account limiter ride their own internal accounting today; both
+are tracked as follow-ups in WORKSPACE-ROADMAP.md.

-### Implications for multi-replica deployments
+### Backend internals

- **Effective per-replica cap is the documented cap.** A 2-replica
-  deployment lets through up to 2× the per-key window cap before
-  either replica rejects.
- **Restart resets the bucket.** A `kubectl rollout restart` empties
-  the in-memory windows on every replica. An attacker who notices
-  this could in principle re-issue burst attempts after every roll;
-  the threat model accepts this because rollouts are operator-driven
-  and the relevant endpoints already require credentials.
- **No cross-replica fan-out.** Rate-limit decisions on replica A
-  are not visible to replica B. Sticky-session ingress routing (with
-  `service.spec.sessionAffinity: ClientIP` on Kubernetes or the
-  equivalent on your load balancer) tightens the effective cap to
-  per-replica + per-source-IP rather than per-replica + per-source-IP
-  for whichever pod the request happened to land on.
+Both backends share the algorithm: sliding-window log + per-key
+bucket + prune-on-Allow.

-If your threat model requires globally-enforced rate limits across
-replicas, the implementation surface is roughly: swap the per-process
-map for a database-backed sliding window (or a Redis-backed equivalent
-if you already run Redis). This is on the
-[WORKSPACE-ROADMAP.md](../../WORKSPACE-ROADMAP.md) as a v3 item;
-nothing in the certctl threat model today requires it.
+**Memory backend (`memory`)** — per-process map keyed by bucket key;
+mutex-guarded; package-level LRU cap prevents unbounded growth under
+adversarial key cardinality (default 100,000 keys per limiter
+instance; oldest-by-newest-timestamp evicted under pressure).
+Implemented at `internal/ratelimit/sliding_window.go`.
+
+**Postgres backend (`postgres`)** — same algorithm against the
+`rate_limit_buckets` table:
+
+```sql
+CREATE TABLE rate_limit_buckets (
+    bucket_key TEXT          PRIMARY KEY,
+    timestamps TIMESTAMPTZ[] NOT NULL DEFAULT '{}',
+    updated_at TIMESTAMPTZ   NOT NULL DEFAULT NOW()
+);
+```
+
+`Allow(key, now)` opens a transaction, ensures the row exists
+(`INSERT ... ON CONFLICT DO NOTHING`), acquires the row lock
+(`SELECT ... FOR UPDATE`), prunes timestamps older than `now-window`,
+compares the post-prune count against `maxN`, conditionally appends
+`now`, persists, and commits. The row lock is what arbitrates across
+replicas: replicas A and B firing simultaneous `Allow("k")` never
+race because Postgres serializes the per-key row update across the
+cluster. Implemented at
+`internal/ratelimit/postgres_sliding_window.go`.
+
+### Janitor sweep (postgres backend only)
+
+The scheduler runs a `rate_limit_buckets` janitor every
+`CERTCTL_RATE_LIMIT_JANITOR_INTERVAL` (default 5m, minimum 1m). The
+sweep deletes rows whose `updated_at` is older than the longest
+configured window any limiter uses (24h today, matching the EST
+per-principal limiter). Idempotent; repeated sweeps find zero rows.
+The memory backend's prune-on-Allow path keeps buckets short-lived
+without a separate sweep, so the loop is a no-op when
+`backend=memory`.
+
+### Falsifiable closure proof
+
+The Phase 13 Sprint 13.2 integration test
+`internal/integration/ratelimit_multi_replica_test.go`
+(`//go:build integration`) fires 100 concurrent `Allow("test-key")`
+calls round-robined across 3 independent `PostgresSlidingWindowLimiter`
+instances sharing one Postgres database (`cap=10`, `window=1m`) and
+asserts exactly 10 succeed + 90 return `ErrRateLimited`. If the
+cross-replica row lock weren't arbitrating, each replica would
+independently let through ~3-4 requests, giving 12-15 successes
+total. Re-run:
+
+```
+go test -tags=integration -count=1 -run TestRateLimit_MultiReplica \
+    ./internal/integration/...
+```
+
+### Helm chart wiring
+
+The helm chart at `deploy/helm/certctl/` exposes the backend via
+`server.rateLimiting.backend` (default `memory`). To opt into the
+postgres backend for an HA deploy:
+
+```
+helm upgrade --install certctl deploy/helm/certctl \
+    --set server.replicas=3 \
+    --set server.rateLimiting.backend=postgres \
+    --set server.rateLimiting.janitorInterval=5m
+```
+
+`server.replicas > 1` without flipping `backend` to `postgres` works
+fine — the limits stay per-process — but the operator gets a 2× /
+3× / Nx effective cap depending on replica count. The chart does NOT
+auto-flip on `replicas > 1` because some HA deploys deliberately want
+per-process limits (sticky-session ingress + tight per-replica caps
+to detect bot traffic at the edge before it hits the application).

 ### Where these numbers live

@@ -4,12 +4,12 @@
 <!-- Re-run after adding or removing any t.Skip(). CI guard:    -->
 <!-- scripts/ci-guards/skip-inventory-drift.sh                  -->

-> Last reviewed: 2026-05-13
+> Last reviewed: 2026-05-14

 ## Summary

- Total t.Skip sites: **142**
- testing.Short() guards: **76** (these gate behind `go test -short`)
+- Total t.Skip sites: **144**
+- testing.Short() guards: **78** (these gate behind `go test -short`)

 Re-run inventory with: `./scripts/skip-inventory.sh`.

@@ -156,6 +156,8 @@ Re-run inventory with: `./scripts/skip-inventory.sh`.

 ### `internal/ratelimit`

+- `internal/ratelimit/equivalence_test.go:80` — t.Skip("race-style test under -short")
+- `internal/ratelimit/equivalence_test.go:88` — t.Skip("postgres equivalence tests require testcontainers; skipped under -short")
 - `internal/ratelimit/sliding_window_test.go:146` — t.Skip("race-style test under -short")

 ### `internal/repository/postgres`
@@ -78,7 +78,7 @@ type AuthBreakglassHandler struct {
 	// nil-safe: when unset, the handler skips the limiter check and
 	// relies on the service-layer Argon2id lockout. Production deploys
 	// MUST set this via SetLoginRateLimiter.
-	loginLimiter *ratelimit.SlidingWindowLimiter
+	loginLimiter ratelimit.Limiter
 }

 // NewAuthBreakglassHandler constructs the handler.
@@ -89,7 +89,7 @@ func NewAuthBreakglassHandler(svc BreakglassService, cookieAttrs SessionCookieAt
 // SetLoginRateLimiter wires the per-source-IP rate limiter the Login
 // handler enforces. Bundle 5 closure (S1) — see the AuthBreakglassHandler
 // type docstring for the full rationale.
-func (h *AuthBreakglassHandler) SetLoginRateLimiter(l *ratelimit.SlidingWindowLimiter) {
+func (h *AuthBreakglassHandler) SetLoginRateLimiter(l ratelimit.Limiter) {
 	h.loginLimiter = l
 }

@@ -52,7 +52,7 @@ type CertificateService interface {
 // CertificateHandler handles HTTP requests for certificate operations.
 type CertificateHandler struct {
 	svc         CertificateService
-	ocspLimiter *ratelimit.SlidingWindowLimiter // production hardening II Phase 3 — per-source-IP cap on OCSP
+	ocspLimiter ratelimit.Limiter // production hardening II Phase 3 — per-source-IP cap on OCSP
 }

 // NewCertificateHandler creates a new CertificateHandler with a service dependency.
@@ -65,7 +65,7 @@ func NewCertificateHandler(svc CertificateService) CertificateHandler {
 // cmd/server/main.go): 1000 req/min/IP. Setting to nil disables the
 // limit; the limiter's own NewSlidingWindowLimiter(maxN<=0, ...)
 // also produces a no-op limiter, so the env-var-zero case is safe.
-func (h *CertificateHandler) SetOCSPRateLimiter(l *ratelimit.SlidingWindowLimiter) {
+func (h *CertificateHandler) SetOCSPRateLimiter(l ratelimit.Limiter) {
 	h.ocspLimiter = l
 }

@@ -100,13 +100,13 @@ type ESTHandler struct {
 	// EST RFC 7030 hardening Phase 3.3: per-handler source-IP rate
 	// limiter for FAILED HTTP Basic auth attempts. Keyed by sourceIP so
 	// a hostile network segment can't burn through the password.
-	failedBasicLimiter *ratelimit.SlidingWindowLimiter
+	failedBasicLimiter ratelimit.Limiter

 	// EST RFC 7030 hardening Phase 4.2: per-handler per-principal sliding-
 	// window rate limit. Keyed by (CSR-CN, sourceIP) so a stolen
 	// bootstrap cert AND a known device CN can't be used to flood the
 	// issuer. Disabled when nil; configured per-profile.
-	perPrincipalLimiter *ratelimit.SlidingWindowLimiter
+	perPrincipalLimiter ratelimit.Limiter

 	// labelForLog gives observability code a per-profile string to
 	// include in audit log lines / Prometheus labels. Defaults to
@@ -170,7 +170,7 @@ func (h *ESTHandler) SetEnrollmentPassword(pw string) { h.basicPassword = pw }
 // rate limiter. Phase 3.3. Disabled when nil — but Validate() at
 // startup refuses an enabled basic-auth profile without a configured
 // limiter, so a real deploy always wires one.
-func (h *ESTHandler) SetSourceIPRateLimiter(l *ratelimit.SlidingWindowLimiter) {
+func (h *ESTHandler) SetSourceIPRateLimiter(l ratelimit.Limiter) {
 	h.failedBasicLimiter = l
 }

@@ -179,7 +179,7 @@ func (h *ESTHandler) SetSourceIPRateLimiter(l *ratelimit.SlidingWindowLimiter) {
 // every successful enrollment, NOT just failures — the goal is to
 // bound enrollment-flooding from a compromised credential, not just
 // failed-auth brute force.
-func (h *ESTHandler) SetPerPrincipalRateLimiter(l *ratelimit.SlidingWindowLimiter) {
+func (h *ESTHandler) SetPerPrincipalRateLimiter(l ratelimit.Limiter) {
 	h.perPrincipalLimiter = l
 }

@@ -28,7 +28,7 @@ type ExportService interface {
 // ExportHandler handles HTTP requests for certificate export operations.
 type ExportHandler struct {
 	svc           ExportService
-	exportLimiter *ratelimit.SlidingWindowLimiter // production hardening II Phase 3
+	exportLimiter ratelimit.Limiter // production hardening II Phase 3
 }

 // NewExportHandler creates a new ExportHandler with a service dependency.
@@ -40,7 +40,7 @@ func NewExportHandler(svc ExportService) ExportHandler {
 // Production hardening II Phase 3. Default cap (when set in
 // cmd/server/main.go): 50 exports/hr/operator. Setting to nil
 // disables the limit.
-func (h *ExportHandler) SetExportRateLimiter(l *ratelimit.SlidingWindowLimiter) {
+func (h *ExportHandler) SetExportRateLimiter(l ratelimit.Limiter) {
 	h.exportLimiter = l
 }

@@ -441,11 +441,13 @@ func Load() (*Config, error) {
 			},
 		},
 		RateLimit: RateLimitConfig{
-			Enabled:          getEnvBool("CERTCTL_RATE_LIMIT_ENABLED", true),
-			RPS:              getEnvFloat("CERTCTL_RATE_LIMIT_RPS", 50),
-			BurstSize:        getEnvInt("CERTCTL_RATE_LIMIT_BURST", 100),
-			PerUserRPS:       getEnvFloat("CERTCTL_RATE_LIMIT_PER_USER_RPS", 0),
-			PerUserBurstSize: getEnvInt("CERTCTL_RATE_LIMIT_PER_USER_BURST", 0),
+			Enabled:                      getEnvBool("CERTCTL_RATE_LIMIT_ENABLED", true),
+			RPS:                          getEnvFloat("CERTCTL_RATE_LIMIT_RPS", 50),
+			BurstSize:                    getEnvInt("CERTCTL_RATE_LIMIT_BURST", 100),
+			PerUserRPS:                   getEnvFloat("CERTCTL_RATE_LIMIT_PER_USER_RPS", 0),
+			PerUserBurstSize:             getEnvInt("CERTCTL_RATE_LIMIT_PER_USER_BURST", 0),
+			SlidingWindowBackend:         getEnv("CERTCTL_RATE_LIMIT_BACKEND", "memory"),
+			SlidingWindowJanitorInterval: getEnvDuration("CERTCTL_RATE_LIMIT_JANITOR_INTERVAL", 5*time.Minute),
 		},
 		CORS: CORSConfig{
 			AllowedOrigins: getEnvList("CERTCTL_CORS_ORIGINS", nil),
@@ -764,6 +766,36 @@ func (c *Config) Validate() error {
 		)
 	}

+	// Phase 13 Sprint 13.3 closure (ARCH-M1): validate
+	// CERTCTL_RATE_LIMIT_BACKEND is one of the two supported values.
+	// Fail-closed on any other input so a typo doesn't silently fall
+	// back to the wrong backend (the operator picked "postgress" and
+	// got memory rate-limits in a 3-replica cluster).
+	switch c.RateLimit.SlidingWindowBackend {
+	case "", "memory", "postgres":
+		// "" is treated as "memory" — test-built Configs (which
+		// construct the struct literal directly without going
+		// through Load()) don't get the default; Load() always
+		// fills "memory". Either path lands the runtime on the
+		// in-memory backend.
+	default:
+		return fmt.Errorf(
+			"invalid CERTCTL_RATE_LIMIT_BACKEND=%q — refuse to start: must be \"memory\" (default, per-process limits; for single-replica deploys) or \"postgres\" (cross-replica-consistent via the rate_limit_buckets table; required for HA deploys). See docs/operator/observability.md.",
+			c.RateLimit.SlidingWindowBackend,
+		)
+	}
+	// Janitor interval lower bound — 1 minute. Below this the sweep
+	// cost outweighs the row-cleanup benefit; above this still
+	// matches the operator's bound (5 minutes default; can be raised
+	// indefinitely).
+	if c.RateLimit.SlidingWindowJanitorInterval > 0 &&
+		c.RateLimit.SlidingWindowJanitorInterval < time.Minute {
+		return fmt.Errorf(
+			"invalid CERTCTL_RATE_LIMIT_JANITOR_INTERVAL=%v — refuse to start: must be ≥ 1 minute (default 5m).",
+			c.RateLimit.SlidingWindowJanitorInterval,
+		)
+	}
+
 	// Validate database configuration
 	if c.Database.URL == "" {
 		return fmt.Errorf("database URL is required")
@@ -321,6 +321,46 @@ type RateLimitConfig struct {
 	// zero, BurstSize is used. Default: 0 (use BurstSize).
 	// Setting: CERTCTL_RATE_LIMIT_PER_USER_BURST environment variable.
 	PerUserBurstSize int
+
+	// SlidingWindowBackend selects which backend implements the
+	// per-key sliding-window-log limiters wired in cmd/server/main.go
+	// (break-glass login, OCSP per-IP, cert-export per-actor, EST
+	// per-principal, EST failed-basic source-IP). Distinct from the
+	// token-bucket fields above — those are middleware RPS limits
+	// applied across every request via the http handler chain; this
+	// field controls the sliding-window-log primitive used by
+	// authenticated-but-shared-credential code paths.
+	//
+	// Valid values:
+	//   "memory"   — per-process, sync.Mutex-guarded map (historical
+	//                default; perfect for single-replica deploys).
+	//   "postgres" — cross-replica-consistent via the
+	//                rate_limit_buckets table (migration 000046).
+	//                SELECT FOR UPDATE arbitrates per-key access
+	//                across the cluster. Adds ~2 DB round-trips per
+	//                Allow call; acceptable on the gated hot path.
+	//
+	// Default: "memory". HA deploys with server.replicas > 1 should
+	// flip to "postgres" so a 2-replica deployment doesn't effectively
+	// double the per-key cap.
+	//
+	// Phase 13 Sprint 13.2/13.3 closure (architecture diligence audit
+	// ARCH-M1). See docs/operator/observability.md.
+	//
+	// Setting: CERTCTL_RATE_LIMIT_BACKEND environment variable.
+	SlidingWindowBackend string
+
+	// SlidingWindowJanitorInterval is how often the scheduler sweeps
+	// stale rows from rate_limit_buckets. A row is stale when its
+	// updated_at is older than the longest configured window any
+	// caller uses (currently 24h for the EST per-principal limiter).
+	// Default: 5 minutes. Minimum: 1 minute. No-op when
+	// SlidingWindowBackend = "memory" (the in-memory backend's
+	// prune-on-Allow path keeps buckets short-lived without a
+	// separate sweep).
+	//
+	// Setting: CERTCTL_RATE_LIMIT_JANITOR_INTERVAL environment variable.
+	SlidingWindowJanitorInterval time.Duration
 }

 // CORSConfig contains CORS configuration.
@@ -0,0 +1,195 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+
+//go:build integration
+
+package integration
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+	"sync"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	_ "github.com/lib/pq"
+	"github.com/testcontainers/testcontainers-go"
+	"github.com/testcontainers/testcontainers-go/wait"
+
+	"github.com/certctl-io/certctl/internal/ratelimit"
+)
+
+// Phase 13 Sprint 13.2 closure (2026-05-14, architecture diligence audit
+// ARCH-M1) — the falsifiable closure proof for cross-replica rate-limit
+// consistency.
+//
+// Scenario:
+//   - ONE postgres container (representing the shared backend).
+//   - N=3 independent *PostgresSlidingWindowLimiter instances pointing
+//     at it (representing 3 server replicas — each replica's process
+//     has its own constructed limiter, but they all share the same
+//     database state).
+//   - 100 concurrent Allow("test-key") calls spread across the 3
+//     limiters via sync.WaitGroup.
+//   - Assert: exactly 10 succeed + 90 return ErrRateLimited.
+//
+// If the postgres backend's SELECT FOR UPDATE serialization weren't
+// arbitrating across the 3 limiters, more than 10 calls would be
+// allowed (each replica would independently let through 10/3 ≈ 4
+// requests, giving ~12-15 successes depending on scheduling). The
+// hard-pass on exactly-10 is what makes ARCH-M1 closure substantive
+// rather than wishful.
+//
+// Gated by //go:build integration matching the rest of
+// internal/integration/. Sprint 13.3 promotes this test to a
+// required CI status check.
+
+func TestRateLimit_PostgresBackend_CapEnforcedAcrossReplicas(t *testing.T) {
+	const (
+		replicas      = 3
+		cap           = 10
+		window        = 1 * time.Minute
+		concurrentReq = 100
+		key           = "test-key"
+	)
+
+	ctx := context.Background()
+
+	// Boot a shared postgres container.
+	container, dsn := startPostgresContainer(ctx, t)
+	t.Cleanup(func() { _ = container.Terminate(context.Background()) })
+
+	// Each "replica" gets its own *sql.DB pool — same database, different
+	// connection pool — matching how N server processes would each open
+	// their own pool to the same control-plane database.
+	dbs := make([]*sql.DB, replicas)
+	for i := 0; i < replicas; i++ {
+		db, err := sql.Open("postgres", dsn)
+		if err != nil {
+			t.Fatalf("open db (replica %d): %v", i, err)
+		}
+		db.SetMaxOpenConns(8)
+		if err := db.Ping(); err != nil {
+			t.Fatalf("ping (replica %d): %v", i, err)
+		}
+		t.Cleanup(func() { db.Close() })
+		dbs[i] = db
+	}
+
+	// Apply the rate_limit_buckets migration via dbs[0]. All replicas
+	// see the same schema since they share the same database.
+	migPath := findMigrationFromHere("000046_rate_limit_buckets.up.sql")
+	body, err := os.ReadFile(migPath)
+	if err != nil {
+		t.Fatalf("read migration: %v", err)
+	}
+	if _, err := dbs[0].ExecContext(ctx, string(body)); err != nil {
+		t.Fatalf("apply migration: %v", err)
+	}
+
+	// Instantiate one limiter per replica.
+	limiters := make([]*ratelimit.PostgresSlidingWindowLimiter, replicas)
+	for i := 0; i < replicas; i++ {
+		limiters[i] = ratelimit.NewPostgresSlidingWindowLimiter(dbs[i], cap, window)
+	}
+
+	// Fire concurrentReq parallel Allow calls, round-robining across the
+	// replicas. Each call uses the SAME key + a SHARED `now` so the
+	// scenario is deterministic. The cross-replica row lock is what
+	// enforces the cap globally.
+	var (
+		allowed int64
+		denied  int64
+		wg      sync.WaitGroup
+	)
+	now := time.Now()
+	for i := 0; i < concurrentReq; i++ {
+		wg.Add(1)
+		go func(idx int) {
+			defer wg.Done()
+			l := limiters[idx%replicas]
+			err := l.Allow(key, now)
+			if err == nil {
+				atomic.AddInt64(&allowed, 1)
+			} else if errors.Is(err, ratelimit.ErrRateLimited) {
+				atomic.AddInt64(&denied, 1)
+			} else {
+				t.Errorf("unexpected error from Allow: %v", err)
+			}
+		}(i)
+	}
+	wg.Wait()
+
+	gotAllowed := atomic.LoadInt64(&allowed)
+	gotDenied := atomic.LoadInt64(&denied)
+
+	t.Logf("replicas=%d cap=%d concurrent=%d → allowed=%d denied=%d",
+		replicas, cap, concurrentReq, gotAllowed, gotDenied)
+
+	if gotAllowed != int64(cap) {
+		t.Errorf("allowed = %d, want exactly %d (cross-replica row lock should serialize Allow calls so exactly cap succeed)",
+			gotAllowed, cap)
+	}
+	if gotDenied != int64(concurrentReq-cap) {
+		t.Errorf("denied = %d, want %d (concurrentReq - cap)", gotDenied, concurrentReq-cap)
+	}
+}
+
+// ----------------------------------------------------------------
+// Local testcontainers harness. Kept in-file because the rest of
+// internal/integration/ uses HTTP-against-running-server smoke tests
+// against a docker-compose stack — different shape from ours.
+// ----------------------------------------------------------------
+
+func startPostgresContainer(ctx context.Context, t *testing.T) (testcontainers.Container, string) {
+	t.Helper()
+
+	req := testcontainers.ContainerRequest{
+		Image:        "postgres:16-alpine",
+		ExposedPorts: []string{"5432/tcp"},
+		Env: map[string]string{
+			"POSTGRES_DB":       "certctl_test",
+			"POSTGRES_USER":     "certctl",
+			"POSTGRES_PASSWORD": "certctl",
+		},
+		WaitingFor: wait.ForLog("database system is ready to accept connections").WithOccurrence(2),
+	}
+	container, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{
+		ContainerRequest: req,
+		Started:          true,
+	})
+	if err != nil {
+		t.Fatalf("start postgres container: %v", err)
+	}
+
+	host, err := container.Host(ctx)
+	if err != nil {
+		t.Fatalf("container host: %v", err)
+	}
+	port, err := container.MappedPort(ctx, "5432")
+	if err != nil {
+		t.Fatalf("container port: %v", err)
+	}
+	dsn := fmt.Sprintf("postgres://certctl:certctl@%s:%s/certctl_test?sslmode=disable",
+		host, port.Port())
+	return container, dsn
+}
+
+func findMigrationFromHere(filename string) string {
+	_, here, _, _ := runtime.Caller(0)
+	dir := filepath.Dir(here)
+	for i := 0; i < 6; i++ {
+		candidate := filepath.Join(dir, "migrations", filename)
+		if _, err := os.Stat(candidate); err == nil {
+			return candidate
+		}
+		dir = filepath.Dir(dir)
+	}
+	return ""
+}
@@ -0,0 +1,412 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+
+package ratelimit_test
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	_ "github.com/lib/pq"
+	"github.com/testcontainers/testcontainers-go"
+	"github.com/testcontainers/testcontainers-go/wait"
+
+	"github.com/certctl-io/certctl/internal/ratelimit"
+)
+
+// Phase 13 Sprint 13.2 closure (2026-05-14, architecture diligence audit
+// ARCH-M1): backend-equivalence test suite. Runs the same scenario
+// surface against both backends (in-memory + postgres) via the shared
+// Limiter interface — if the postgres backend's caller-visible
+// semantics drift from the memory backend's, this file fails first.
+//
+// Mirrors the white-box test names in sliding_window_test.go: every
+// public-surface behavior pinned there (cap, expiry, disabled bypass,
+// empty-key short-circuit, concurrency) gets re-pinned here for the
+// postgres backend.
+//
+// Postgres tests skip under -short (matches the pattern in
+// internal/repository/postgres/testutil_test.go); CI's
+// `go test -race -short -count=1 ./...` exercises only the memory
+// half. The integration job runs the full suite.
+
+// ----------------------------------------------------------------
+// Backend-equivalence helpers
+// ----------------------------------------------------------------
+
+// limiterFactory builds a fresh Limiter for one test case.
+// Memory backends discard `db`; postgres backends use it.
+type limiterFactory func(t *testing.T, db *sql.DB, maxN int, window time.Duration) ratelimit.Limiter
+
+func memoryFactory(t *testing.T, _ *sql.DB, maxN int, window time.Duration) ratelimit.Limiter {
+	t.Helper()
+	// Map cap of 10_000 — large enough that none of the equivalence
+	// scenarios trip the LRU-eviction branch (the eviction branch is
+	// memory-specific; postgres has no equivalent so it's not part of
+	// the cross-backend contract).
+	return ratelimit.NewSlidingWindowLimiter(maxN, window, 10_000)
+}
+
+func postgresFactory(t *testing.T, db *sql.DB, maxN int, window time.Duration) ratelimit.Limiter {
+	t.Helper()
+	if db == nil {
+		t.Fatal("postgresFactory requires a non-nil *sql.DB")
+	}
+	return ratelimit.NewPostgresSlidingWindowLimiter(db, maxN, window)
+}
+
+// ----------------------------------------------------------------
+// Per-backend test entry points
+// ----------------------------------------------------------------
+
+func TestSlidingWindowLimiter_Equivalence_Memory(t *testing.T) {
+	t.Run("AllowsUpToCap", func(t *testing.T) { caseAllowsUpToCap(t, memoryFactory, nil) })
+	t.Run("DistinctKeysIndependent", func(t *testing.T) { caseDistinctKeysIndependent(t, memoryFactory, nil) })
+	t.Run("WindowExpiry", func(t *testing.T) { caseWindowExpiry(t, memoryFactory, nil) })
+	t.Run("DisabledBypass", func(t *testing.T) { caseDisabledBypass(t, memoryFactory, nil) })
+	t.Run("NegativeCapDisabled", func(t *testing.T) { caseNegativeCapDisabled(t, memoryFactory, nil) })
+	t.Run("EmptyKeyShortCircuits", func(t *testing.T) { caseEmptyKeyShortCircuits(t, memoryFactory, nil) })
+	t.Run("ConcurrentRaceFree", func(t *testing.T) {
+		if testing.Short() {
+			t.Skip("race-style test under -short")
+		}
+		caseConcurrentRaceFree(t, memoryFactory, nil)
+	})
+}
+
+func TestSlidingWindowLimiter_Equivalence_Postgres(t *testing.T) {
+	if testing.Short() {
+		t.Skip("postgres equivalence tests require testcontainers; skipped under -short")
+	}
+	tdb := setupTestDB(t)
+	defer tdb.teardown(t)
+
+	t.Run("AllowsUpToCap", func(t *testing.T) {
+		db := tdb.freshSchema(t, "AllowsUpToCap")
+		caseAllowsUpToCap(t, postgresFactory, db)
+	})
+	t.Run("DistinctKeysIndependent", func(t *testing.T) {
+		db := tdb.freshSchema(t, "DistinctKeysIndependent")
+		caseDistinctKeysIndependent(t, postgresFactory, db)
+	})
+	t.Run("WindowExpiry", func(t *testing.T) {
+		db := tdb.freshSchema(t, "WindowExpiry")
+		caseWindowExpiry(t, postgresFactory, db)
+	})
+	t.Run("DisabledBypass", func(t *testing.T) {
+		db := tdb.freshSchema(t, "DisabledBypass")
+		caseDisabledBypass(t, postgresFactory, db)
+	})
+	t.Run("NegativeCapDisabled", func(t *testing.T) {
+		db := tdb.freshSchema(t, "NegativeCapDisabled")
+		caseNegativeCapDisabled(t, postgresFactory, db)
+	})
+	t.Run("EmptyKeyShortCircuits", func(t *testing.T) {
+		db := tdb.freshSchema(t, "EmptyKeyShortCircuits")
+		caseEmptyKeyShortCircuits(t, postgresFactory, db)
+	})
+	t.Run("ConcurrentRaceFree", func(t *testing.T) {
+		db := tdb.freshSchema(t, "ConcurrentRaceFree")
+		caseConcurrentRaceFree(t, postgresFactory, db)
+	})
+}
+
+// ----------------------------------------------------------------
+// Backend-agnostic test cases (one per behavior pinned in
+// sliding_window_test.go's public-surface tests)
+// ----------------------------------------------------------------
+
+func caseAllowsUpToCap(t *testing.T, mk limiterFactory, db *sql.DB) {
+	l := mk(t, db, 3, 24*time.Hour)
+	now := time.Now()
+	for i := 0; i < 3; i++ {
+		if err := l.Allow("k", now.Add(time.Duration(i)*time.Minute)); err != nil {
+			t.Fatalf("call %d should be allowed: %v", i+1, err)
+		}
+	}
+	if err := l.Allow("k", now.Add(4*time.Minute)); !errors.Is(err, ratelimit.ErrRateLimited) {
+		t.Fatalf("4th call should be rate-limited; got %v", err)
+	}
+}
+
+func caseDistinctKeysIndependent(t *testing.T, mk limiterFactory, db *sql.DB) {
+	l := mk(t, db, 1, 24*time.Hour)
+	now := time.Now()
+
+	if err := l.Allow("k-1", now); err != nil {
+		t.Fatalf("first allow: %v", err)
+	}
+	if err := l.Allow("k-2", now); err != nil {
+		t.Fatalf("different key must have its own bucket: %v", err)
+	}
+	if err := l.Allow("k-1", now.Add(1*time.Second)); !errors.Is(err, ratelimit.ErrRateLimited) {
+		t.Fatalf("repeat key should be limited; got %v", err)
+	}
+}
+
+func caseWindowExpiry(t *testing.T, mk limiterFactory, db *sql.DB) {
+	l := mk(t, db, 2, 1*time.Hour)
+	now := time.Now()
+
+	if err := l.Allow("k", now); err != nil {
+		t.Fatal(err)
+	}
+	if err := l.Allow("k", now.Add(30*time.Minute)); err != nil {
+		t.Fatal(err)
+	}
+	// Inside window — limited.
+	if err := l.Allow("k", now.Add(45*time.Minute)); !errors.Is(err, ratelimit.ErrRateLimited) {
+		t.Fatalf("inside-window 3rd call should be limited: %v", err)
+	}
+	// Past window — slots reopen.
+	if err := l.Allow("k", now.Add(2*time.Hour)); err != nil {
+		t.Fatalf("past-window call should be allowed (window reset): %v", err)
+	}
+}
+
+func caseDisabledBypass(t *testing.T, mk limiterFactory, db *sql.DB) {
+	l := mk(t, db, 0, 24*time.Hour) // maxN=0 → disabled
+	type disablable interface {
+		Disabled() bool
+	}
+	if d, ok := l.(disablable); ok && !d.Disabled() {
+		t.Fatal("limiter with maxN=0 must report Disabled()=true")
+	}
+	now := time.Now()
+	for i := 0; i < 100; i++ {
+		if err := l.Allow("k", now); err != nil {
+			t.Fatalf("disabled limiter must allow everything: %v", err)
+		}
+	}
+}
+
+func caseNegativeCapDisabled(t *testing.T, mk limiterFactory, db *sql.DB) {
+	l := mk(t, db, -1, 24*time.Hour)
+	type disablable interface {
+		Disabled() bool
+	}
+	if d, ok := l.(disablable); ok && !d.Disabled() {
+		t.Fatal("negative maxN must produce a disabled limiter")
+	}
+	now := time.Now()
+	if err := l.Allow("k", now); err != nil {
+		t.Fatalf("disabled limiter must allow: %v", err)
+	}
+}
+
+func caseEmptyKeyShortCircuits(t *testing.T, mk limiterFactory, db *sql.DB) {
+	// Empty key is the caller's defense-in-depth case — caller's
+	// validation upstream should reject empty-key events first. Limiter
+	// must not build a single shared bucket keyed by empty-key — that
+	// would be a chokepoint for every empty-key event.
+	l := mk(t, db, 1, 24*time.Hour)
+	now := time.Now()
+	for i := 0; i < 50; i++ {
+		if err := l.Allow("", now); err != nil {
+			t.Fatalf("empty key must short-circuit (call %d): %v", i, err)
+		}
+	}
+}
+
+func caseConcurrentRaceFree(t *testing.T, mk limiterFactory, db *sql.DB) {
+	l := mk(t, db, 50, 24*time.Hour)
+	var wg sync.WaitGroup
+	for g := 0; g < 20; g++ {
+		wg.Add(1)
+		go func(id int) {
+			defer wg.Done()
+			now := time.Now()
+			key := fmt.Sprintf("k-%d", id)
+			for i := 0; i < 30; i++ {
+				_ = l.Allow(key, now)
+			}
+		}(g)
+	}
+	wg.Wait()
+}
+
+// ----------------------------------------------------------------
+// Postgres-only testcontainers harness — mirrors
+// internal/repository/postgres/testutil_test.go's setupTestDB +
+// freshSchema pattern.
+// ----------------------------------------------------------------
+
+type testDB struct {
+	db        *sql.DB
+	container testcontainers.Container
+}
+
+func setupTestDB(t *testing.T) *testDB {
+	t.Helper()
+	ctx := context.Background()
+
+	req := testcontainers.ContainerRequest{
+		Image:        "postgres:16-alpine",
+		ExposedPorts: []string{"5432/tcp"},
+		Env: map[string]string{
+			"POSTGRES_DB":       "certctl_test",
+			"POSTGRES_USER":     "certctl",
+			"POSTGRES_PASSWORD": "certctl",
+		},
+		WaitingFor: wait.ForLog("database system is ready to accept connections").WithOccurrence(2),
+	}
+	container, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{
+		ContainerRequest: req,
+		Started:          true,
+	})
+	if err != nil {
+		t.Fatalf("start postgres container: %v", err)
+	}
+
+	host, err := container.Host(ctx)
+	if err != nil {
+		t.Fatalf("container host: %v", err)
+	}
+	port, err := container.MappedPort(ctx, "5432")
+	if err != nil {
+		t.Fatalf("container port: %v", err)
+	}
+
+	connStr := fmt.Sprintf("postgres://certctl:certctl@%s:%s/certctl_test?sslmode=disable", host, port.Port())
+	db, err := sql.Open("postgres", connStr)
+	if err != nil {
+		t.Fatalf("open db: %v", err)
+	}
+	// Pool size > 1 so the multi-goroutine concurrency case can hold
+	// multiple connections simultaneously; the row-lock arbitrates.
+	db.SetMaxOpenConns(8)
+
+	if err := db.Ping(); err != nil {
+		t.Fatalf("ping: %v", err)
+	}
+
+	return &testDB{db: db, container: container}
+}
+
+func (tdb *testDB) teardown(t *testing.T) {
+	t.Helper()
+	if tdb.db != nil {
+		tdb.db.Close()
+	}
+	if tdb.container != nil {
+		_ = tdb.container.Terminate(context.Background())
+	}
+}
+
+// freshSchema creates an isolated schema per test case + runs the
+// rate_limit_buckets migration inside it. Returns a *sql.DB whose
+// search_path is scoped to the new schema.
+//
+// Note: this helper takes a sub-test label (caller-supplied) so the
+// schema name is deterministic-per-case + stable across runs. The
+// canonical postgres testutil uses t.Name() but we're inside Run-
+// nested subtests where t.Name() includes "/" — flatten it.
+func (tdb *testDB) freshSchema(t *testing.T, label string) *sql.DB {
+	t.Helper()
+	schema := sanitizeSchemaName(label + "_" + t.Name())
+	ctx := context.Background()
+
+	// One connection-scoped session so SET search_path persists.
+	conn, err := tdb.db.Conn(ctx)
+	if err != nil {
+		t.Fatalf("acquire conn: %v", err)
+	}
+
+	if _, err := conn.ExecContext(ctx, fmt.Sprintf("CREATE SCHEMA IF NOT EXISTS %s", schema)); err != nil {
+		t.Fatalf("create schema: %v", err)
+	}
+	if _, err := conn.ExecContext(ctx, fmt.Sprintf("SET search_path TO %s, public", schema)); err != nil {
+		t.Fatalf("set search_path: %v", err)
+	}
+
+	// Run the rate_limit_buckets migration in this schema. The migration
+	// is the only one that introduces our table; other migrations don't
+	// matter for limiter behavior.
+	migPath := findMigration("000046_rate_limit_buckets.up.sql")
+	body, err := os.ReadFile(migPath)
+	if err != nil {
+		t.Fatalf("read migration: %v", err)
+	}
+	if _, err := conn.ExecContext(ctx, string(body)); err != nil {
+		t.Fatalf("apply migration: %v", err)
+	}
+
+	t.Cleanup(func() {
+		conn.ExecContext(context.Background(), fmt.Sprintf("DROP SCHEMA IF EXISTS %s CASCADE", schema))
+		conn.Close()
+	})
+
+	// Wrap the single connection in a *sql.DB-like by returning a fresh
+	// pool that goes through the same search_path. Simpler: just return
+	// the underlying *sql.DB and SET search_path session-wide by re-
+	// running the SET on every checkout. The cleanest move is to use
+	// the per-connection helper: return a *sql.DB that's actually a
+	// "limited to N=1 connection with search_path pinned" handle.
+	//
+	// Workaround the easy way: build a fresh *sql.DB whose dsn embeds
+	// search_path as a connection-time setting, so every connection
+	// auto-applies it.
+	dsn := connDSNWithSearchPath(tdb, schema)
+	scoped, err := sql.Open("postgres", dsn)
+	if err != nil {
+		t.Fatalf("open scoped db: %v", err)
+	}
+	scoped.SetMaxOpenConns(8)
+	t.Cleanup(func() { scoped.Close() })
+
+	// Sanity: row exists / table exists.
+	if _, err := scoped.ExecContext(ctx, "SELECT 1 FROM rate_limit_buckets LIMIT 1"); err != nil && !strings.Contains(err.Error(), "no rows") {
+		// Empty table is fine; only a missing-table error matters.
+		// "no rows" never fires here (we used Exec not Query).
+		t.Fatalf("smoke select: %v", err)
+	}
+
+	return scoped
+}
+
+func connDSNWithSearchPath(tdb *testDB, schema string) string {
+	// Derive the DSN by introspection of the container's host/port.
+	// Couldn't pre-store because freshSchema can be called many times.
+	ctx := context.Background()
+	host, _ := tdb.container.Host(ctx)
+	port, _ := tdb.container.MappedPort(ctx, "5432")
+	return fmt.Sprintf(
+		"postgres://certctl:certctl@%s:%s/certctl_test?sslmode=disable&search_path=%s,public",
+		host, port.Port(), schema,
+	)
+}
+
+func sanitizeSchemaName(name string) string {
+	name = strings.ToLower(name)
+	for _, ch := range []string{"/", " ", "-", "."} {
+		name = strings.ReplaceAll(name, ch, "_")
+	}
+	if len(name) > 50 {
+		name = name[:50]
+	}
+	return "test_rl_" + name
+}
+
+func findMigration(filename string) string {
+	_, here, _, _ := runtime.Caller(0)
+	// here = .../internal/ratelimit/equivalence_test.go
+	// migrations = .../migrations
+	dir := filepath.Dir(here)
+	for i := 0; i < 6; i++ {
+		candidate := filepath.Join(dir, "migrations", filename)
+		if _, err := os.Stat(candidate); err == nil {
+			return candidate
+		}
+		dir = filepath.Dir(dir)
+	}
+	return ""
+}
@@ -0,0 +1,65 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+
+package ratelimit
+
+import (
+	"database/sql"
+	"fmt"
+	"time"
+)
+
+// Phase 13 Sprint 13.3 (2026-05-14, architecture diligence audit
+// ARCH-M1): the backend-selector factory. Wires every
+// `ratelimit.NewSlidingWindowLimiter(...)` call site in
+// cmd/server/main.go through here so the operator-chosen backend
+// (CERTCTL_RATE_LIMIT_BACKEND={memory,postgres}) gates the limiter
+// type without each call site replicating the switch.
+//
+// Caller-visible behavior contract: NewLimiter(backend="memory", ...)
+// returns a *SlidingWindowLimiter identical to a direct
+// NewSlidingWindowLimiter call. NewLimiter(backend="postgres", ...)
+// returns a *PostgresSlidingWindowLimiter with the same Allow(key, now)
+// signature + the same ErrRateLimited sentinel + the same maxN<=0
+// disabled semantics. Sprint 13.3's "no signature change" rule is
+// what makes the swap drop-in.
+//
+// The mapCap argument is the in-memory backend's per-instance
+// key-cap (LRU-evicted under pressure). Postgres backend has no
+// equivalent — the table grows until the scheduler janitor sweeps
+// stale rows; mapCap is accepted + ignored for that backend so the
+// factory signature stays drop-in identical to NewSlidingWindowLimiter.
+
+// NewLimiter returns a Limiter backed by either the in-memory
+// SlidingWindowLimiter (backend="memory") or the
+// PostgresSlidingWindowLimiter (backend="postgres").
+//
+// `backend` is validated by config.Validate() at startup; any other
+// value here panics — config validation is the SoT, this is just
+// defensive in case the call site somehow bypasses startup
+// validation.
+//
+// `db` is required when backend="postgres" and ignored when
+// backend="memory". The factory does not nil-check db for the
+// memory branch because requiring a meaningful db handle for the
+// memory path would couple every limiter call site to the database
+// pool unnecessarily.
+//
+// `maxN <= 0` disables the limiter (both backends honor the
+// opt-out — all Allow calls return nil).
+func NewLimiter(backend string, db *sql.DB, maxN int, window time.Duration, mapCap int) Limiter {
+	switch backend {
+	case "memory":
+		return NewSlidingWindowLimiter(maxN, window, mapCap)
+	case "postgres":
+		if db == nil {
+			panic("ratelimit.NewLimiter: backend=postgres requires a non-nil *sql.DB (config.Validate should have caught this earlier)")
+		}
+		return NewPostgresSlidingWindowLimiter(db, maxN, window)
+	default:
+		// Defensive — config.Validate() rejects anything else at
+		// startup. Reaching this branch implies a coding error in a
+		// future call site that bypasses validation.
+		panic(fmt.Sprintf("ratelimit.NewLimiter: unknown backend %q (must be memory or postgres)", backend))
+	}
+}
@@ -0,0 +1,54 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+
+package ratelimit
+
+import "time"
+
+// Limiter is the rate-limit primitive every caller in cmd/server +
+// internal/api/handler + internal/service consumes. Two backends
+// satisfy this interface:
+//
+//   - SlidingWindowLimiter (in-memory; the historical default;
+//     declared in sliding_window.go).
+//   - PostgresSlidingWindowLimiter (cross-replica-consistent;
+//     declared in postgres_sliding_window.go; introduced in Phase 13
+//     Sprint 13.2 for the ARCH-M1 substantive close).
+//
+// Sprint 13.3 (next) wires every call site through the operator-
+// chosen backend via the CERTCTL_RATELIMIT_BACKEND={memory,postgres}
+// env var. Until then, both backends compile + tests for both pass,
+// but the production call sites still construct SlidingWindowLimiter
+// directly.
+//
+// Sprint 13.2 signature note: the prompt template specified
+// `Allow(key string) error`, but the actual repo signature has been
+// `Allow(key string, now time.Time) error` since the EST RFC 7030
+// hardening master bundle Phase 4.1 — the `now` parameter is what
+// makes the memory limiter testable against synthetic time. The
+// interface matches the actual signature so the existing
+// SlidingWindowLimiter satisfies Limiter without a method-set change.
+//
+// Per CLAUDE.md "the repo is truth" principle, code grounded against
+// the live signature (not the prompt's draft).
+type Limiter interface {
+	// Allow records a request at the given key/time and returns
+	// ErrRateLimited if the configured cap is exceeded inside the
+	// configured window. nil otherwise.
+	//
+	// Empty `key` short-circuits to nil (caller's defense-in-depth;
+	// caller upstream validation should reject empty-key events
+	// first — building a single shared bucket keyed by empty-key
+	// would be a chokepoint for every empty-key event).
+	//
+	// Disabled limiters (maxN <= 0) return nil for every call.
+	Allow(key string, now time.Time) error
+}
+
+// Compile-time interface satisfaction checks. Drift in either
+// backend's Allow signature fails the build at this file before any
+// caller breaks.
+var (
+	_ Limiter = (*SlidingWindowLimiter)(nil)
+	_ Limiter = (*PostgresSlidingWindowLimiter)(nil)
+)
@@ -0,0 +1,71 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+
+package ratelimit
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"time"
+)
+
+// Phase 13 Sprint 13.3 closure (2026-05-14, architecture diligence audit
+// ARCH-M1): the scheduler-invoked janitor for the postgres-backed
+// rate-limit bucket table. Sweeps rows whose updated_at is older than
+// the longest configured window any caller uses — these rows can
+// never be at-cap (every timestamp inside has aged past the window),
+// so dropping them entirely is safe.
+//
+// The in-memory backend's prune-on-Allow path keeps buckets short-
+// lived without a separate sweep; this file is postgres-only.
+
+// PostgresGC drives the rate_limit_buckets sweep. Constructed from the
+// same *sql.DB the limiters use; the scheduler holds it as a value
+// satisfying the ratelimit.GarbageCollector interface (mirrors the
+// shape of acme.GarbageCollector + sessions.GarbageCollector).
+type PostgresGC struct {
+	db        *sql.DB
+	maxWindow time.Duration
+}
+
+// NewPostgresGC returns a janitor that sweeps rows whose updated_at
+// is older than `maxWindow` ago. Pass the longest window any caller
+// in the deployment configures (the EST per-principal limiter uses
+// 24h today; bump if a new caller introduces a longer window).
+//
+// maxWindow <= 0 disables the sweep — GarbageCollect becomes a
+// no-op. Operator opt-out for sketchpad / single-replica deploys
+// that still want the postgres backend (rare; the memory backend is
+// the better fit).
+func NewPostgresGC(db *sql.DB, maxWindow time.Duration) *PostgresGC {
+	return &PostgresGC{db: db, maxWindow: maxWindow}
+}
+
+// GarbageCollect deletes every rate_limit_buckets row whose
+// updated_at is older than now-maxWindow. Returns the number of
+// rows deleted + any error from the DELETE.
+//
+// Single statement, single round-trip — operates on the
+// rate_limit_buckets_updated_at_idx index introduced in migration
+// 000046. Idempotent: repeated calls find 0 rows.
+func (g *PostgresGC) GarbageCollect(ctx context.Context) (int64, error) {
+	if g.maxWindow <= 0 {
+		return 0, nil
+	}
+	cutoff := time.Now().Add(-g.maxWindow)
+	res, err := g.db.ExecContext(ctx, `
+		DELETE FROM rate_limit_buckets
+		WHERE updated_at < $1
+	`, cutoff)
+	if err != nil {
+		return 0, fmt.Errorf("ratelimit-gc: delete stale buckets: %w", err)
+	}
+	n, err := res.RowsAffected()
+	if err != nil {
+		// Driver doesn't expose RowsAffected; rare. Don't fail the
+		// sweep — the delete already ran.
+		return 0, nil
+	}
+	return n, nil
+}
@@ -0,0 +1,228 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+
+package ratelimit
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/lib/pq"
+)
+
+// Phase 13 Sprint 13.2 closure (2026-05-14, architecture diligence audit
+// ARCH-M1): the cross-replica-consistent rate-limit backend. Same
+// algorithm as SlidingWindowLimiter (prune-on-Allow sliding-window log)
+// but the state lives in postgres so N replicas see the same per-key
+// bucket. Replaces the per-process in-memory limit when the operator
+// sets CERTCTL_RATELIMIT_BACKEND=postgres (wired in Sprint 13.3).
+//
+// Algorithm
+// =========
+// Each Allow call runs a single BEGIN/COMMIT transaction:
+//
+//  1. INSERT ... ON CONFLICT (bucket_key) DO NOTHING — ensure the
+//     row exists so the SELECT FOR UPDATE below has something to lock.
+//  2. SELECT timestamps FROM rate_limit_buckets WHERE bucket_key=$1
+//     FOR UPDATE — acquire the per-key row lock for the rest of the
+//     transaction.
+//  3. Prune timestamps older than (now - window) in Go (reusing the
+//     unexported pruneOlderThan helper shared with SlidingWindowLimiter
+//     — single source of truth for the prune semantics).
+//  4. If cardinality(pruned) >= maxN: persist the pruned state without
+//     appending, COMMIT, return ErrRateLimited.
+//  5. Else: append `now`, persist, COMMIT, return nil.
+//
+// SELECT FOR UPDATE serializes Allow calls for the same key across
+// replicas: replicas A and B firing simultaneous Allow("k") never
+// race because Postgres' row-lock arbitrates. This is the entire
+// reason for the close — the memory backend's sync.Mutex only
+// arbitrates within a process; pg's row lock arbitrates the cluster.
+//
+// Why a transaction (not a single CTE)
+// ====================================
+// A "compute everything in one SQL statement" approach using
+// INSERT ... ON CONFLICT DO UPDATE SET timestamps = CASE WHEN ... is
+// possible but the conditional logic to gate the append on the
+// pruned-cardinality requires nested CTEs whose check-then-act
+// semantics are hard to read + harder to convince yourself are
+// race-free across all isolation levels. The explicit transaction
+// version above is correct under READ COMMITTED (Postgres' default),
+// matches the memory backend's read-decide-write shape line-for-line,
+// and shares the same prune helper. Two extra round-trips per Allow
+// vs one is acceptable for the rate-limit hot path — the operation
+// is gated anyway.
+//
+// Sprint 13.3 will wire the scheduler janitor loop that GCs rows
+// whose updated_at is older than the longest configured window; the
+// migration ships the supporting btree index on updated_at.
+
+// PostgresSlidingWindowLimiter implements Limiter against the
+// rate_limit_buckets table introduced in migration 000046.
+//
+// Constructed via NewPostgresSlidingWindowLimiter. The zero value is
+// NOT usable — the db handle is required.
+//
+// Concurrency: safe for concurrent Allow calls across goroutines AND
+// across N replicas (the underlying SELECT FOR UPDATE serializes
+// per-key access across the cluster).
+type PostgresSlidingWindowLimiter struct {
+	db       *sql.DB
+	maxN     int
+	window   time.Duration
+	disabled bool // maxN <= 0 → all Allow calls return nil
+}
+
+// NewPostgresSlidingWindowLimiter returns a limiter with the given
+// per-key cap + window. maxN <= 0 disables the limiter (all Allow
+// calls return nil); matches the memory backend's opt-out semantics
+// for test harnesses + sketchpad deploys.
+//
+// Window defaults to 24h when zero, mirroring SlidingWindowLimiter.
+//
+// The db argument is required + must outlive the limiter. Construction
+// itself does NOT touch the database — DDL is owned by migration
+// 000046_rate_limit_buckets.up.sql which runs at boot via
+// cmd/server's RunMigrations path.
+func NewPostgresSlidingWindowLimiter(db *sql.DB, maxN int, window time.Duration) *PostgresSlidingWindowLimiter {
+	if window <= 0 {
+		window = 24 * time.Hour
+	}
+	disabled := maxN <= 0
+	return &PostgresSlidingWindowLimiter{
+		db:       db,
+		maxN:     maxN,
+		window:   window,
+		disabled: disabled,
+	}
+}
+
+// Allow records a request at the given (key, now) and returns
+// ErrRateLimited if the configured cap is exceeded inside the
+// configured window. Matches SlidingWindowLimiter.Allow byte-for-byte
+// in caller-visible semantics so Sprint 13.3's backend-selector swap
+// is signature-clean.
+//
+// The `now` argument is the timestamp the call is "happening at".
+// Used as the prune cutoff (entries older than now-window are dropped)
+// and as the new appended entry. Tests pass synthetic `now` values
+// to exercise window-expiry deterministically; production call sites
+// pass time.Now() (matching how SlidingWindowLimiter is invoked
+// today — see internal/api/handler/{est,export,certificates,
+// auth_breakglass}.go).
+//
+// Empty `key` short-circuits to nil (matches the memory backend's
+// chokepoint-avoidance contract).
+func (l *PostgresSlidingWindowLimiter) Allow(key string, now time.Time) error {
+	if l.disabled {
+		return nil
+	}
+	if key == "" {
+		return nil
+	}
+
+	ctx := context.Background()
+	tx, err := l.db.BeginTx(ctx, &sql.TxOptions{Isolation: sql.LevelReadCommitted})
+	if err != nil {
+		return fmt.Errorf("ratelimit: begin tx: %w", err)
+	}
+	defer func() {
+		// Rollback is a no-op once the tx is committed; safe to defer
+		// unconditionally for the error paths.
+		_ = tx.Rollback()
+	}()
+
+	// Step 1: ensure the row exists so SELECT FOR UPDATE has something
+	// to lock. ON CONFLICT DO NOTHING is a no-op when the row already
+	// exists.
+	if _, err := tx.ExecContext(ctx, `
+		INSERT INTO rate_limit_buckets (bucket_key, timestamps, updated_at)
+		VALUES ($1, '{}', $2)
+		ON CONFLICT (bucket_key) DO NOTHING
+	`, key, now); err != nil {
+		return fmt.Errorf("ratelimit: ensure row: %w", err)
+	}
+
+	// Step 2: lock the row + read current state. lib/pq cannot scan a
+	// TIMESTAMPTZ[] column back into []time.Time directly: time.Time
+	// does not implement sql.Scanner, and pq.GenericArray's per-element
+	// scan path calls Scan() (not database/sql's convertAssign), so the
+	// inner Scan fails with
+	//   "pq: scanning to time.Time is not implemented; only sql.Scanner".
+	// Workaround: ask Postgres to format each timestamp as a canonical
+	// ISO 8601 UTC string via to_char(... AT TIME ZONE 'UTC', ...), read
+	// the column as text[] via pq.StringArray (well-supported), and
+	// parse Go-side. The to_char format is fully deterministic (6-digit
+	// microseconds, "T" separator, "Z" suffix) regardless of the
+	// session's DateStyle / TimeZone settings.
+	const pgTimestampLayout = "2006-01-02T15:04:05.000000Z"
+	var tsStrings pq.StringArray
+	if err := tx.QueryRowContext(ctx, `
+		SELECT COALESCE(
+			ARRAY(
+				SELECT to_char(t AT TIME ZONE 'UTC', 'YYYY-MM-DD"T"HH24:MI:SS.US"Z"')
+				FROM unnest(timestamps) AS t
+			),
+			ARRAY[]::text[]
+		)
+		FROM rate_limit_buckets
+		WHERE bucket_key = $1
+		FOR UPDATE
+	`, key).Scan(&tsStrings); err != nil {
+		// Shouldn't happen — step 1 ensured the row exists. Treat
+		// the sql.ErrNoRows path as a no-op (be conservative; never
+		// over-limit on transient DB weirdness).
+		if errors.Is(err, sql.ErrNoRows) {
+			return nil
+		}
+		return fmt.Errorf("ratelimit: select-for-update: %w", err)
+	}
+	ts := make([]time.Time, 0, len(tsStrings))
+	for _, s := range tsStrings {
+		parsed, err := time.Parse(pgTimestampLayout, s)
+		if err != nil {
+			return fmt.Errorf("ratelimit: parse stored timestamp %q: %w", s, err)
+		}
+		ts = append(ts, parsed.UTC())
+	}
+
+	// Step 3: prune in Go via the shared helper. Same prune semantics
+	// as SlidingWindowLimiter — single source of truth.
+	cutoff := now.Add(-l.window)
+	pruned := pruneOlderThan(ts, cutoff)
+
+	// Step 4: decide.
+	rateLimited := len(pruned) >= l.maxN
+	if !rateLimited {
+		pruned = append(pruned, now)
+	}
+
+	// Step 5: persist.
+	if _, err := tx.ExecContext(ctx, `
+		UPDATE rate_limit_buckets
+		SET timestamps = $2, updated_at = $3
+		WHERE bucket_key = $1
+	`, key, pq.Array(pruned), now); err != nil {
+		return fmt.Errorf("ratelimit: update: %w", err)
+	}
+
+	if err := tx.Commit(); err != nil {
+		return fmt.Errorf("ratelimit: commit: %w", err)
+	}
+
+	if rateLimited {
+		return ErrRateLimited
+	}
+	return nil
+}
+
+// Disabled reports whether the limiter is in opt-out mode (maxN <= 0).
+// Mirrors SlidingWindowLimiter.Disabled() so handler-side gating +
+// admin-endpoint observability can ask the same question of either
+// backend.
+func (l *PostgresSlidingWindowLimiter) Disabled() bool {
+	return l.disabled
+}
@@ -103,6 +103,21 @@ type BCLReplayGarbageCollector interface {
 	SweepExpired(ctx context.Context, now time.Time) (int, error)
 }

+// RateLimitGarbageCollector sweeps stale rows from the
+// rate_limit_buckets table introduced in migration 000046. Phase 13
+// Sprint 13.3 (ARCH-M1 closure completion) — wired only when
+// CERTCTL_RATE_LIMIT_BACKEND=postgres. Concrete impl is
+// *ratelimit.PostgresGC. Mirrors the ACMEGarbageCollector +
+// SessionGarbageCollector contracts so the scheduler reuses the same
+// atomic.Bool + WithTimeout + ticker pattern as the existing GC loops.
+//
+// Returns the row count to surface via observability logs (matches
+// SessionGarbageCollector's shape — the operator wants to see
+// "how many buckets did the sweep delete" in steady-state monitoring).
+type RateLimitGarbageCollector interface {
+	GarbageCollect(ctx context.Context) (int64, error)
+}
+
 // JobReaperService defines the interface for job timeout reaping used by the scheduler.
 type JobReaperService interface {
 	ReapTimedOutJobs(ctx context.Context, csrTTL, approvalTTL time.Duration) error
@@ -130,6 +145,7 @@ type Scheduler struct {
 	acmeGC                ACMEGarbageCollector
 	sessionGC             SessionGarbageCollector
 	bclReplayGC           BCLReplayGarbageCollector
+	rateLimitGC           RateLimitGarbageCollector
 	jobReaper             JobReaperService
 	logger                *slog.Logger

@@ -149,6 +165,7 @@ type Scheduler struct {
 	jobTimeoutInterval            time.Duration
 	acmeGCInterval                time.Duration
 	sessionGCInterval             time.Duration
+	rateLimitGCInterval           time.Duration
 	// agentOfflineJobTTL: per-tick threshold for reaping Running jobs whose
 	// owning agent has been silent. Bundle C / Audit M-016. Defaults below.
 	agentOfflineJobTTL      time.Duration
@@ -171,6 +188,7 @@ type Scheduler struct {
 	jobTimeoutRunning            atomic.Bool
 	acmeGCRunning                atomic.Bool
 	sessionGCRunning             atomic.Bool
+	rateLimitGCRunning           atomic.Bool

 	// Graceful shutdown: wait for in-flight work to complete
 	wg sync.WaitGroup
@@ -209,6 +227,7 @@ func NewScheduler(
 		jobTimeoutInterval:            10 * time.Minute,
 		acmeGCInterval:                1 * time.Minute,
 		sessionGCInterval:             1 * time.Hour,
+		rateLimitGCInterval:           5 * time.Minute,
 		// 5 minutes is 5×agentHealthCheckInterval default of 1m; an agent
 		// must miss multiple heartbeats before its in-flight jobs are reaped.
 		agentOfflineJobTTL: 5 * time.Minute,
@@ -365,6 +384,29 @@ func (s *Scheduler) SetSessionGCInterval(d time.Duration) {
 	s.sessionGCInterval = d
 }

+// SetRateLimitGarbageCollector wires the Phase 13 Sprint 13.3 rate-
+// limit bucket GC. Optional; nil disables the loop (which is the
+// correct behavior when CERTCTL_RATE_LIMIT_BACKEND=memory — the
+// in-memory backend's prune-on-Allow path keeps buckets short-lived
+// without a separate sweep).
+//
+// Concrete impl is *ratelimit.PostgresGC, constructed in
+// cmd/server/main.go only when the postgres backend is selected.
+func (s *Scheduler) SetRateLimitGarbageCollector(gc RateLimitGarbageCollector) {
+	s.rateLimitGC = gc
+}
+
+// SetRateLimitGCInterval configures the interval at which the rate-
+// limit GC sweep runs. Default 5m. Wire:
+// CERTCTL_RATE_LIMIT_JANITOR_INTERVAL. Zero or negative values are
+// ignored.
+func (s *Scheduler) SetRateLimitGCInterval(d time.Duration) {
+	if d <= 0 {
+		return
+	}
+	s.rateLimitGCInterval = d
+}
+
 // SetAgentOfflineJobTTL sets the threshold past which a Running job whose
 // owning agent has gone silent is reaped to Failed. Bundle C / Audit M-016.
 // Zero or negative values are ignored (the default of 5 minutes is kept).
@@ -426,6 +468,9 @@ func (s *Scheduler) Start(ctx context.Context) <-chan struct{} {
 		if s.sessionGC != nil {
 			loopCount++
 		}
+		if s.rateLimitGC != nil {
+			loopCount++
+		}
 		s.wg.Add(loopCount)

 		go func() { defer s.wg.Done(); s.renewalCheckLoop(ctx) }()
@@ -457,6 +502,9 @@ func (s *Scheduler) Start(ctx context.Context) <-chan struct{} {
 		if s.sessionGC != nil {
 			go func() { defer s.wg.Done(); s.sessionGCLoop(ctx) }()
 		}
+		if s.rateLimitGC != nil {
+			go func() { defer s.wg.Done(); s.rateLimitGCLoop(ctx) }()
+		}

 		// Signal that all loops are launched
 		close(startedChan)
@@ -1247,3 +1295,45 @@ func (s *Scheduler) sessionGCLoop(ctx context.Context) {
 		}
 	}
 }
+
+// rateLimitGCLoop runs every rateLimitGCInterval and invokes
+// RateLimitGarbageCollector.GarbageCollect, which sweeps stale rows
+// from the rate_limit_buckets table introduced in Phase 13 Sprint
+// 13.2's migration 000046.
+//
+// Wired only when CERTCTL_RATE_LIMIT_BACKEND=postgres (the in-memory
+// backend's prune-on-Allow path keeps buckets short-lived without a
+// separate sweep — cmd/server/main.go skips SetRateLimitGarbageCollector
+// for that case so this loop never launches).
+//
+// Phase 13 Sprint 13.3 closure. The atomic.Bool guard + per-tick
+// context.WithTimeout match every other GC loop's pattern.
+func (s *Scheduler) rateLimitGCLoop(ctx context.Context) {
+	ticker := NewJitteredTicker(s.rateLimitGCInterval, DefaultSchedulerJitter)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-ticker.C:
+			if !s.rateLimitGCRunning.CompareAndSwap(false, true) {
+				s.logger.Warn("rate-limit GC sweep still running, skipping tick")
+				continue
+			}
+			s.wg.Add(1)
+			go func() {
+				defer s.wg.Done()
+				defer s.rateLimitGCRunning.Store(false)
+				// 1-minute timeout matches acme + session GC loops.
+				opCtx, cancel := context.WithTimeout(ctx, time.Minute)
+				defer cancel()
+				if n, err := s.rateLimitGC.GarbageCollect(opCtx); err != nil {
+					s.logger.Warn("rate-limit gc sweep failed (next tick will retry)", "error", err)
+				} else if n > 0 {
+					s.logger.Debug("rate-limit gc swept stale buckets", "rows", n)
+				}
+			}()
+		}
+	}
+}
@@ -0,0 +1,6 @@
+-- Phase 13 Sprint 13.2 reversal — drop the rate-limit bucket table.
+-- Down migrations are not run in production; this file exists for
+-- developer-side rollback during integration testing.
+
+DROP INDEX IF EXISTS rate_limit_buckets_updated_at_idx;
+DROP TABLE IF EXISTS rate_limit_buckets;
@@ -0,0 +1,28 @@
+-- Phase 13 Sprint 13.2 closure (2026-05-14, architecture diligence audit
+-- ARCH-M1): introduce a postgres-backed sliding-window rate limiter so
+-- per-process / in-memory limits become cross-replica-consistent when
+-- the operator sets CERTCTL_RATELIMIT_BACKEND=postgres (wired in
+-- Sprint 13.3).
+--
+-- One row per (bucket_key) — caller composes the key the same way the
+-- memory backend already does (e.g. "subject|issuer" for SCEP/Intune,
+-- "srcIP|peek" for EST failed-basic, raw "actor" for export, etc.).
+-- The `timestamps` array stores the in-window log; prune-on-Allow
+-- keeps it bounded by the limiter's maxN cap.
+--
+-- updated_at + the index on it support the Sprint 13.3 scheduler
+-- janitor loop: any row whose updated_at is older than the longest
+-- configured window is safely deletable.
+--
+-- Per CLAUDE.md "Idempotent migrations" architecture decision:
+-- IF NOT EXISTS on every statement. Re-running this migration is
+-- a no-op on a database that already has the table.
+
+CREATE TABLE IF NOT EXISTS rate_limit_buckets (
+    bucket_key TEXT          PRIMARY KEY,
+    timestamps TIMESTAMPTZ[] NOT NULL DEFAULT '{}',
+    updated_at TIMESTAMPTZ   NOT NULL DEFAULT NOW()
+);
+
+CREATE INDEX IF NOT EXISTS rate_limit_buckets_updated_at_idx
+    ON rate_limit_buckets (updated_at);
@@ -81,6 +81,8 @@ Count: re-derive on demand via `ls scripts/ci-guards/*.sh | wc -l`. The table be
 | `bundle-8-M-009-bare-usemutation` | M-009 + M-029 mutation contract | Bare `useMutation()` outside `useTrackedMutation` wrapper |
 | `H-1-encryption-key-min-length` | H-1 closure follow-up (post-Phase-5 surfacing) | `CERTCTL_CONFIG_ENCRYPTION_KEY` literal in any `deploy/docker-compose*.yml` shorter than the 32-byte floor enforced by `internal/config/config.go::Validate()` |
 | `test-compose-scep-coherence` | post-Phase-5 surfacing of dead SCEP test config | `CERTCTL_SCEP_ENABLED=true` in test compose without (a) a CI job that runs the SCEP integration test, (b) the `ra.crt` + `ra.key` + `intune_trust_anchor.pem` fixtures committed to `deploy/test/fixtures/`, AND (c) the matching volume mount |
+| `openapi-handler-parity` | ARCH-H1 OpenAPI ↔ handler drift | Router routes vs OpenAPI operations vs documented exceptions (wire-protocol vs rest-deferred buckets). Supports `--bucket=wire-protocol\|rest-deferred` subcommand for sibling guards. |
+| `openapi-rest-deferred-monotonic` | ARCH-H1 Phase 13 Sprint 13.1 — rest-deferred bucket monotonic-decrease | `category: rest-deferred` count growing vs the checked-in baseline at `api/openapi-handler-exceptions-baseline.txt`. Sprints 13.4-13.6 drive this to zero; Sprint 13.7 tightens to a zero-exact pin. |

 ### Forward-looking guards (Auditable Codebase Bundle, post-v2.1.0 anti-rot)

@@ -104,3 +106,34 @@ for g in scripts/ci-guards/*.sh; do
  bash "$g" || echo "  FAILED"
 done
 ```
+
+## ARCH-H1 OpenAPI exception two-bucket contract (Phase 13 Sprint 13.1)
+
+`api/openapi-handler-exceptions.yaml` lists every router route that is intentionally NOT in `api/openapi.yaml`. Each entry carries a required `category:` field with one of two values:
+
+- **`category: wire-protocol`** — the route's wire shape is dictated by an IETF RFC (SCEP RFC 8894, ACME RFC 8555, ACME ARI RFC 9773, EST RFC 7030) or it's a sibling/shorthand variant of one. The canonical reference for these endpoints lives in `docs/acme-server.md` + `docs/operator/scep.md` + `docs/operator/est.md` — duplicating their wire contract in `openapi.yaml` would add no information. **Wire-protocol entries never burn down.**
+
+- **`category: rest-deferred`** — the route is REST-shaped (resource CRUD, JSON request/response, RBAC-gated) but its OpenAPI operation was deferred when the handler shipped. **Rest-deferred entries must monotonically decrease to zero.** Authoring an OpenAPI op for a deferred route + deleting the corresponding exception entry + decrementing `api/openapi-handler-exceptions-baseline.txt` in the same PR is the canonical close path.
+
+### Adding a new exception entry
+
+The default category for new entries is `rest-deferred`. Only set `wire-protocol` when:
+
+1. The `why:` field cites a specific RFC anchor (e.g. "RFC 8555 §7.1.1 directory"), AND
+2. The route's wire shape is dictated by the RFC (not a REST resource that happens to live alongside one).
+
+When in doubt, default to `rest-deferred` and author the OpenAPI op. The two guards in this directory enforce both buckets:
+
+- `openapi-handler-parity.sh` reports bucket counts + fails on missing/unknown `category:` fields + fails on stale exceptions / undocumented router routes.
+- `openapi-rest-deferred-monotonic.sh` fails if `rest-deferred` grows vs the baseline file at `api/openapi-handler-exceptions-baseline.txt`.
+
+### Inspecting bucket counts
+
+```bash
+# Full report.
+bash scripts/ci-guards/openapi-handler-parity.sh
+
+# Just one bucket count (used by sibling guards).
+bash scripts/ci-guards/openapi-handler-parity.sh --bucket=wire-protocol
+bash scripts/ci-guards/openapi-handler-parity.sh --bucket=rest-deferred
+```
@@ -0,0 +1,47 @@
+#!/usr/bin/env bash
+# Phase 6 closure (I18N-H2 regression gate): fail CI when a new
+# `new Date(x).toLocaleString()` or `.toLocaleDateString()` ships in
+# production tsx outside the canonical web/src/api/utils.ts impls.
+#
+# Pre-Phase-6 the codebase had 8 raw sites across 6 pages, each making
+# its own locale + timezone choice. Phase 6 routed them through the
+# formatDateTime / formatDate / <Timestamp> helpers in utils.ts +
+# components/Timestamp.tsx. This guard prevents new raw sites from
+# landing.
+#
+# Allowlist: web/src/api/utils.ts itself — those raw calls ARE the
+# canonical implementation everyone else routes through.
+#
+# Tests are excluded (web/src/**/*.test.*) so test fixtures + assertions
+# describing the pre-Phase-6 raw pattern don't trip the guard.
+set -euo pipefail
+
+cd "$(dirname "$0")/../../web"
+
+OFFENDERS=$(
+  grep -rnE 'new Date\([^)]*\)\.toLocaleString\(\)|new Date\([^)]*\)\.toLocaleDateString\(\)' \
+    src \
+    --include='*.tsx' \
+    --include='*.ts' \
+    --exclude='*.test.*' \
+    --exclude-dir='node_modules' \
+    --exclude-dir='dist' \
+    2>/dev/null \
+    | grep -v 'src/api/utils.ts:' \
+    || true
+)
+
+if [[ -n "$OFFENDERS" ]]; then
+  echo "::error::I18N-H2 regression: raw new Date(x).toLocaleString() outside web/src/api/utils.ts:"
+  echo "$OFFENDERS"
+  echo ""
+  echo "Migrate to one of:"
+  echo "  • <Timestamp iso={...} />            — for hover-shows-other-zone UX"
+  echo "  • formatDateTime(iso)                 — for local-zone date+time text"
+  echo "  • formatDate(iso) / formatDateUTC(iso) — for date-only text"
+  echo ""
+  echo "All three live in web/src/api/utils.ts / web/src/components/Timestamp.tsx."
+  exit 1
+fi
+
+echo "I18N-H2 no-raw-toLocaleString: clean."
@@ -0,0 +1 @@
+134
@@ -0,0 +1,103 @@
+#!/usr/bin/env bash
+# Phase 5 closure (UX-H4 regression gate): fail the build when a new
+# <label> element ships in production tsx without htmlFor= or a wrapping
+# <FormField> primitive (which auto-emits htmlFor via useId()).
+#
+# Pre-Phase-5: 139 <label> tags, 6 with htmlFor, 0 inputs with id —
+# WCAG 1.3.1 fails on ~99% of form fields. The FormField primitive
+# (web/src/components/FormField.tsx) closes new label/input pairs by
+# construction; this guard prevents reintroducing unbound labels in
+# untouched parts of the codebase.
+#
+# Grace period: during the Phase 5 migration we expect ~133 existing
+# unbound labels to stay in place until each owning page migrates
+# through. They live in the allowlist file alongside this script
+# (no-unbound-label-exceptions.txt). Each migration deletes the
+# corresponding line; when the allowlist is empty, this guard becomes
+# strictly enforcing and the allowlist file should be removed.
+#
+# Known false-positive class: wrap-style implicit-association labels —
+# `<label><input/>...</label>`. These ARE a11y-safe (browsers + screen
+# readers pair the wrapped input with the label automatically — no
+# htmlFor needed), but this guard's line-based regex can't tell the
+# wrap pattern apart from a sibling-label-no-htmlFor bug. When such
+# patterns ship, raise the baseline with a one-line explanation in
+# the commit message; they're benign. Phase 6 added 2 (the timestamp-
+# mode radios in AuthSettingsPage), so baseline 132 → 134.
+#
+# Algorithm:
+#   1. Count current unbound labels (labels NOT preceded by htmlFor= on
+#      the same line OR within the wrapping JSX block).
+#   2. Compare against the allowlist's recorded count. If today's count
+#      is HIGHER than the allowlist baseline, a new unbound label was
+#      added — fail with the diff.
+#   3. If today's count is LOWER, congratulate and remind to update
+#      the baseline.
+#
+# Strict mode: pass `--strict` to fail on any unbound label, ignoring
+# the allowlist. Use once the allowlist is empty.
+set -euo pipefail
+
+# Resolve script dir BEFORE cd so baseline path stays valid.
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+BASELINE_FILE="$SCRIPT_DIR/no-unbound-label-baseline.txt"
+
+cd "$SCRIPT_DIR/../../web"
+
+STRICT=0
+[[ "${1:-}" == "--strict" ]] && STRICT=1
+
+# Count <label tags WITHOUT htmlFor= on the same line in production
+# tsx (excludes tests + node_modules + dist).
+COUNT_UNBOUND=$(
+  grep -rohE '<label[^>]*>' src \
+    --include='*.tsx' \
+    --exclude='*.test.*' \
+    --exclude-dir='__tests__' \
+    --exclude-dir='node_modules' \
+    --exclude-dir='dist' \
+    2>/dev/null \
+    | grep -vcE 'htmlFor='
+) || true
+
+BASELINE=0
+if [[ -f "$BASELINE_FILE" ]]; then
+  BASELINE=$(cat "$BASELINE_FILE" | tr -d '[:space:]')
+fi
+
+echo "Unbound <label> tags in web/src — current: $COUNT_UNBOUND, baseline: $BASELINE"
+
+if [[ $STRICT -eq 1 ]]; then
+  if [[ $COUNT_UNBOUND -gt 0 ]]; then
+    echo "FAIL (--strict): $COUNT_UNBOUND unbound <label> tag(s) remain. Migrate to <FormField> or add htmlFor=."
+    exit 1
+  fi
+  echo "PASS (--strict): zero unbound <label> tags."
+  exit 0
+fi
+
+if [[ $COUNT_UNBOUND -gt $BASELINE ]]; then
+  echo ""
+  echo "FAIL: A new unbound <label> tag was added ($COUNT_UNBOUND > baseline $BASELINE)."
+  echo ""
+  echo "Wrap the new label in <FormField label='…'>{<input … />}</FormField> — the"
+  echo "primitive at web/src/components/FormField.tsx auto-pairs label htmlFor with"
+  echo "the child input's id via React's useId() so WCAG 1.3.1 holds by construction."
+  echo ""
+  echo "If a raw <label> is genuinely needed (rare: e.g. wrapping a Headless UI"
+  echo "Switch where Headless UI handles the binding internally), add htmlFor=…"
+  echo "explicitly. Then update the baseline:"
+  echo ""
+  echo "  echo $COUNT_UNBOUND > $BASELINE_FILE"
+  echo ""
+  exit 1
+fi
+
+if [[ $COUNT_UNBOUND -lt $BASELINE ]]; then
+  echo ""
+  echo "PASS — and you're under baseline! Drop the baseline to lock in progress:"
+  echo "  echo $COUNT_UNBOUND > $BASELINE_FILE"
+  echo ""
+fi
+
+exit 0
@@ -7,34 +7,68 @@
 #
 # Per ci-pipeline-cleanup bundle Phase 9 / frozen decision 0.11.
 #
-# Phase 5 reconciliation (2026-05-13):
-#   220 r.Register call sites in internal/api/router/router.go
-#   209 unique (METHOD /path) router routes after de-duplication
-#   158 operationIds in api/openapi.yaml
-#    64 documented exceptions in api/openapi-handler-exceptions.yaml
-#     0 unaccounted router routes — every route is in OpenAPI OR
-#       in the exceptions YAML. Guard passes clean today.
+# Phase 13 Sprint 13.1 (2026-05-14) — every entry in the exceptions
+# YAML now carries a required `category: wire-protocol | rest-deferred`
+# field. This script reports the two buckets alongside the total. The
+# rest-deferred bucket is gated by a sibling guard
+# (openapi-rest-deferred-monotonic.sh) against a checked-in baseline
+# at api/openapi-handler-exceptions-baseline.txt.
 #
-# Of the 64 exceptions:
-#   35 wire-protocol carve-outs (SCEP RFC 8894 = 8, ACME RFC 8555
-#      default + per-profile = 27). These MUST stay as exceptions —
-#      they're protocol contracts, not REST resources.
-#   29 REST-shaped routes deferred from openapi.yaml authoring
-#      (auth sessions, OIDC providers admin, breakglass admin,
-#      users mgmt, runtime-config, demo-residual-cleanup, audit
-#      export). Burn-down target: author the 29 OpenAPI ops over
-#      the next ~2 sprints so the generated client (web/orval.config.ts)
-#      covers them. Tracked under ARCH-H1 in
-#      cowork/certctl-architecture-diligence-audit.html.
+# Current state (post-Sprint-13.7 / 2026-05-14):
+#   220 r.Register / r.mux.Handle call sites in internal/api/router/router.go
+#   186 operationIds in api/openapi.yaml
+#    36 documented exceptions (36 wire-protocol + 0 rest-deferred)
+#     0 unaccounted router routes — guard passes clean today.
+#
+# Sprints 13.4-13.6 drove rest-deferred to zero by authoring 28 OpenAPI
+# ops + deleting the corresponding exception entries. Sprint 13.7
+# (this comment-block update + the inline fail-on-rest-deferred check
+# at the bottom of the python block) tightens this guard's
+# rest-deferred floor from "monotonic-decrease vs baseline" (the
+# sibling guard openapi-rest-deferred-monotonic.sh) to a HARD
+# zero-exact pin. The `category: rest-deferred` escape hatch is now
+# closed for good: any future PR adding a new REST route MUST author
+# its OpenAPI op or fail CI.
+#
+# The sibling monotonic-decrease guard stays in tree as belt-and-
+# suspenders — both must hold. The monotonic guard catches baseline-
+# drift accidents (e.g. an operator manually edits the baseline up
+# without surfacing the rationale); this guard catches the underlying
+# rest-deferred bucket re-growing at all.
 #
 # Going forward: any new gap (in either direction) fails the build
-# unless documented in the exceptions YAML.
+# unless documented in the exceptions YAML with category=wire-protocol
+# (carry an RFC anchor in `why:` for review-time scrutiny).
+#
+# Subcommand:
+#   bash scripts/ci-guards/openapi-handler-parity.sh
+#     Full parity check + bucket reporting.
+#   bash scripts/ci-guards/openapi-handler-parity.sh --bucket=wire-protocol
+#   bash scripts/ci-guards/openapi-handler-parity.sh --bucket=rest-deferred
+#     Print just the count for the named bucket (used by sibling guards
+#     + Sprint 13.7's zero-exact pin). Exit 0 always; informational.

 set -e

-python3 - <<'PY'
+BUCKET=""
+case "${1:-}" in
+    --bucket=wire-protocol|--bucket=rest-deferred)
+        BUCKET="${1#--bucket=}"
+        ;;
+    "")
+        ;;
+    *)
+        echo "::error::unknown argument: $1"
+        echo "usage: $0 [--bucket=wire-protocol|--bucket=rest-deferred]"
+        exit 2
+        ;;
+esac
+
+python3 - "$BUCKET" <<'PY'
 import re, sys, yaml

+bucket_arg = sys.argv[1] if len(sys.argv) > 1 else ""
+
 # Extract router routes: r.mux.Handle("METHOD /path", ...) and
 # r.Register("METHOD /path", ...) — Go 1.22+ ServeMux pattern syntax.
 with open('internal/api/router/router.go') as f:
@@ -60,20 +94,76 @@ try:
 except FileNotFoundError:
    exc_doc = {'documented_exceptions': []}
 exception_set = set()
+bucket_counts = {'wire-protocol': 0, 'rest-deferred': 0}
+missing_category = []
+unknown_category = []
 for entry in (exc_doc.get('documented_exceptions') or []):
    route_str = entry['route']
    parts = route_str.split(maxsplit=1)
    if len(parts) == 2:
        exception_set.add((parts[0], parts[1]))
+    cat = entry.get('category')
+    if cat is None:
+        missing_category.append(route_str)
+    elif cat in bucket_counts:
+        bucket_counts[cat] += 1
+    else:
+        unknown_category.append((route_str, cat))
+
+# --bucket=X subcommand: print just the count, exit 0, no other output.
+if bucket_arg in bucket_counts:
+    print(bucket_counts[bucket_arg])
+    sys.exit(0)

 # Report counts
 print(f"Router routes:                  {len(router_set)}")
 print(f"OpenAPI operations:             {len(oapi_set)}")
 print(f"Documented exceptions:          {len(exception_set)}")
+print(f"  wire-protocol:                {bucket_counts['wire-protocol']}")
+print(f"  rest-deferred:                {bucket_counts['rest-deferred']}")
 print()

 fail = False

+# Phase 13 Sprint 13.1: every entry MUST have a category. Missing or
+# unknown categories fail the build — keeps the bucket math honest.
+if missing_category:
+    print(f"::error::api/openapi-handler-exceptions.yaml: {len(missing_category)} entries missing required `category:` field:")
+    for r in missing_category:
+        print(f"  {r}")
+    print()
+    print("Add `category: wire-protocol` (with an RFC anchor in `why:`) or")
+    print("author the route's OpenAPI op (the rest-deferred bucket is now")
+    print("pinned at zero — see Phase 13 Sprint 13.7 closure).")
+    fail = True
+
+if unknown_category:
+    print(f"::error::api/openapi-handler-exceptions.yaml: {len(unknown_category)} entries with unknown category value (must be wire-protocol or rest-deferred):")
+    for r, c in unknown_category:
+        print(f"  {r}  → category: {c}")
+    fail = True
+
+# Phase 13 Sprint 13.7 — hard zero-exact pin on the rest-deferred
+# bucket. ARCH-H1's substantive close requires that the bucket stay
+# empty in perpetuity: any new REST route MUST land with an
+# OpenAPI op. Categorizing a new exception as `category: rest-deferred`
+# is no longer an escape hatch — it fails CI immediately, surfacing
+# the route + suggesting the fix.
+if bucket_counts['rest-deferred'] > 0:
+    print(f"::error::rest-deferred bucket is non-empty ({bucket_counts['rest-deferred']} entries) — Phase 13 Sprint 13.7 closure pins this at zero.")
+    print()
+    print("Every entry in api/openapi-handler-exceptions.yaml with")
+    print("`category: rest-deferred` represents a REST-shaped route whose")
+    print("OpenAPI op was deferred. Author the OpenAPI op in api/openapi.yaml")
+    print("with a request/response schema mirroring the Go handler's")
+    print("projection types, then delete the exception entry.")
+    print()
+    print("Offending entries:")
+    for entry in (exc_doc.get('documented_exceptions') or []):
+        if entry.get('category') == 'rest-deferred':
+            print(f"  {entry['route']}")
+    fail = True
+
 # Routes in router but NOT in openapi AND NOT in exceptions = drift
 router_only_undocumented = router_set - oapi_set - exception_set
 if router_only_undocumented:
@@ -84,8 +174,9 @@ if router_only_undocumented:
    print("Either:")
    print("  (a) Add the operationId to api/openapi.yaml (preferred for REST endpoints), OR")
    print("  (b) Add the route to api/openapi-handler-exceptions.yaml with a one-line `why:` justification")
-    print("      (only for protocol-shaped or operational routes — health probes,")
-    print("      Prometheus scrape, SCEP/EST/OCSP wire-protocol endpoints, etc.).")
+    print("      AND a `category: wire-protocol | rest-deferred` field (only protocol-shaped")
+    print("      or operational routes — health probes, Prometheus scrape, SCEP/EST/ACME")
+    print("      wire-protocol endpoints, etc. — qualify as wire-protocol).")
    fail = True

 # Routes in openapi but NOT in router = orphan operationId
@@ -0,0 +1,84 @@
+#!/usr/bin/env bash
+# scripts/ci-guards/openapi-rest-deferred-monotonic.sh
+#
+# Phase 13 Sprint 13.1 closure (2026-05-14, architecture diligence audit
+# ARCH-H1): the `rest-deferred` exception bucket in
+# api/openapi-handler-exceptions.yaml MUST monotonically decrease vs
+# the checked-in baseline at api/openapi-handler-exceptions-baseline.txt.
+#
+# Contract:
+#   - openapi-handler-exceptions.yaml entries categorized as
+#     `category: rest-deferred` are REST-shaped routes whose OpenAPI
+#     op was deferred when the handler shipped. They are gaps, not
+#     contracts, and must reach zero.
+#   - This guard reads the current rest-deferred count via the parity
+#     script's --bucket subcommand, reads the baseline from
+#     api/openapi-handler-exceptions-baseline.txt, and fails if the
+#     current count exceeds the baseline.
+#   - Phase 13 Sprints 13.4-13.6 author the OpenAPI ops for the
+#     remaining 28 rest-deferred entries; each batch bumps the
+#     baseline file downward. Sprint 13.7 lands the baseline at 0
+#     AND tightens the sibling openapi-handler-parity.sh guard to a
+#     hard zero-exact pin.
+#
+# Going forward: any PR that adds a new `category: rest-deferred`
+# entry without simultaneously bumping the baseline file fails CI.
+#
+# Operator workflow:
+#   1. Land an OpenAPI op for one of the rest-deferred routes.
+#   2. Delete the corresponding entry from
+#      api/openapi-handler-exceptions.yaml.
+#   3. Decrement api/openapi-handler-exceptions-baseline.txt by the
+#      number of entries removed.
+#   4. Commit all three changes in the same PR — this guard verifies
+#      they stay consistent.
+
+set -e
+
+BASELINE_FILE="api/openapi-handler-exceptions-baseline.txt"
+
+if [ ! -f "$BASELINE_FILE" ]; then
+    echo "::error::missing $BASELINE_FILE — required by Phase 13 Sprint 13.1 contract."
+    echo ""
+    echo "Create it with a single integer matching the current rest-deferred count:"
+    echo "  bash scripts/ci-guards/openapi-handler-parity.sh --bucket=rest-deferred > $BASELINE_FILE"
+    exit 1
+fi
+
+# Whitespace-tolerant read of the baseline.
+BASELINE=$(tr -d '[:space:]' < "$BASELINE_FILE")
+if ! [[ "$BASELINE" =~ ^[0-9]+$ ]]; then
+    echo "::error::$BASELINE_FILE must contain a single non-negative integer; got: '$BASELINE'"
+    exit 1
+fi
+
+CURRENT=$(bash scripts/ci-guards/openapi-handler-parity.sh --bucket=rest-deferred)
+if ! [[ "$CURRENT" =~ ^[0-9]+$ ]]; then
+    echo "::error::openapi-handler-parity.sh --bucket=rest-deferred returned non-integer: '$CURRENT'"
+    exit 1
+fi
+
+if [ "$CURRENT" -gt "$BASELINE" ]; then
+    echo "::error::rest-deferred bucket grew: $CURRENT > baseline $BASELINE."
+    echo ""
+    echo "Phase 13 Sprint 13.1 contract: the rest-deferred bucket in"
+    echo "api/openapi-handler-exceptions.yaml must monotonically decrease."
+    echo ""
+    echo "If you added a new REST route that genuinely cannot be authored into"
+    echo "openapi.yaml yet (e.g. work-in-progress), surface the rationale in"
+    echo "the PR description AND get explicit operator sign-off before"
+    echo "bumping $BASELINE_FILE upward. The default answer is 'author"
+    echo "the OpenAPI op now instead'."
+    exit 1
+fi
+
+if [ "$CURRENT" -lt "$BASELINE" ]; then
+    echo "::error::rest-deferred bucket shrank below baseline: $CURRENT < $BASELINE."
+    echo ""
+    echo "Authoring an OpenAPI op is the right move — but the baseline file"
+    echo "at $BASELINE_FILE must be bumped down in the SAME commit so this"
+    echo "guard's pin tightens automatically. Update it to: $CURRENT"
+    exit 1
+fi
+
+echo "openapi-rest-deferred-monotonic: clean — rest-deferred = $CURRENT, baseline = $BASELINE."
@@ -1,11 +1,11 @@
 <!DOCTYPE html>
-<html lang="en" class="dark">
+<html lang="en">
 <head>
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <title>certctl - Certificate Control Plane</title>
 </head>
-<body class="bg-slate-900 text-slate-100">
+<body class="bg-page text-ink">
  <div id="root"></div>
  <script type="module" src="/src/main.tsx"></script>
 </body>
@@ -14,22 +14,35 @@
    "generate": "orval --config ./orval.config.ts"
  },
  "dependencies": {
+    "@floating-ui/react": "^0.27.19",
+    "@fontsource-variable/inter": "^5.2.8",
+    "@fontsource/jetbrains-mono": "^5.2.8",
+    "@headlessui/react": "^2.2.10",
+    "@hookform/resolvers": "^5.2.2",
    "@tanstack/react-query": "^5.90.21",
+    "cmdk": "^1.1.1",
+    "lucide-react": "^1.16.0",
    "react": "^18.3.1",
    "react-dom": "^18.3.1",
+    "react-hook-form": "^7.75.0",
    "react-router-dom": "^6.30.3",
-    "recharts": "^3.8.0"
+    "recharts": "^3.8.0",
+    "sonner": "^2.0.7",
+    "zod": "^4.4.3"
  },
  "devDependencies": {
+    "@axe-core/react": "^4.11.3",
    "@playwright/test": "^1.49.0",
    "@testing-library/jest-dom": "^6.9.1",
    "@testing-library/react": "^16.3.2",
-    "orval": "^7.0.0",
+    "@types/jest-axe": "^3.5.9",
    "@types/react": "^19.2.14",
    "@types/react-dom": "^19.2.3",
    "@vitejs/plugin-react": "^6.0.1",
    "autoprefixer": "^10.4.27",
+    "jest-axe": "^10.0.0",
    "jsdom": "^29.0.0",
+    "orval": "^7.0.0",
    "postcss": "^8.5.8",
    "tailwindcss": "^3.4.19",
    "typescript": "^5.9.3",
@@ -0,0 +1,73 @@
+import { describe, it, expect } from 'vitest';
+import { formatNumber, formatCompact, formatPercent, formatBytes } from './format';
+
+describe('format', () => {
+  describe('formatNumber', () => {
+    it('formats integers with thousand separator', () => {
+      // Locale-tolerant: any of "5,432" (en) / "5.432" (de) / "5 432" (fr) is fine.
+      const out = formatNumber(5432);
+      expect(out).toMatch(/^5[ .,]?432$/);
+    });
+    it('limits fraction digits to 2', () => {
+      const out = formatNumber(1.23456);
+      expect(out).toMatch(/^1[.,]23$/);
+    });
+    it('returns dash for NaN / Infinity', () => {
+      expect(formatNumber(NaN)).toBe('—');
+      expect(formatNumber(Infinity)).toBe('—');
+    });
+  });
+
+  describe('formatCompact', () => {
+    it('compacts thousands to K', () => {
+      // English: "5.4K"; some locales drop the K. The compact notation
+      // is locale-defined; assert only that the magnitude SCALE is right
+      // (length < raw "5432") rather than pinning a string.
+      const out = formatCompact(5432);
+      expect(out.length).toBeLessThan('5432'.length + 2);
+    });
+    it('compacts millions to M', () => {
+      const out = formatCompact(1_200_000);
+      // any rendering should be much shorter than "1,200,000".
+      expect(out.length).toBeLessThan(10);
+    });
+    it('returns dash for NaN', () => {
+      expect(formatCompact(NaN)).toBe('—');
+    });
+  });
+
+  describe('formatPercent', () => {
+    it('renders 0.995 as 99.5%', () => {
+      const out = formatPercent(0.995);
+      // en: "99.5%"; fr: "99,5 %"; both contain "99" + ("5" or no fraction)
+      expect(out).toMatch(/99[.,]?5?\s?%/);
+    });
+    it('renders 0 as 0%', () => {
+      expect(formatPercent(0)).toMatch(/^0\s?%$/);
+    });
+    it('returns dash for NaN', () => {
+      expect(formatPercent(NaN)).toBe('—');
+    });
+  });
+
+  describe('formatBytes', () => {
+    it('formats < 1KB as bytes', () => {
+      expect(formatBytes(512)).toMatch(/^512 B$/);
+    });
+    it('formats KB scale', () => {
+      const out = formatBytes(5_400);
+      expect(out).toMatch(/KB$/);
+    });
+    it('formats MB scale', () => {
+      const out = formatBytes(5_400_000);
+      expect(out).toMatch(/MB$/);
+    });
+    it('formats GB scale', () => {
+      const out = formatBytes(5_400_000_000);
+      expect(out).toMatch(/GB$/);
+    });
+    it('returns dash for NaN', () => {
+      expect(formatBytes(NaN)).toBe('—');
+    });
+  });
+});
@@ -0,0 +1,133 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Number / byte / percent formatting helpers — Phase 6 closure for
+// I18N-M2 (zero Intl.NumberFormat usage; cert counts via
+// .toLocaleString() on numbers — browser-locale-aware — sit alongside
+// .toFixed(1) not localized at all).
+//
+// All helpers route through `Intl.NumberFormat` with `undefined` for
+// the locale (browser default; same i18n-ready boundary policy as
+// utils.ts). The format objects are constructed ONCE at module load
+// rather than per call — Intl.NumberFormat construction is the
+// expensive part; .format() is cheap.
+//
+// When the i18n framework lands (Phase 10) the only change here is
+// to thread a `locale` arg through; the display code that imports
+// these helpers stays unchanged.
+
+/**
+ * Standard integer / decimal formatter — "5,432.10" in en, "5.432,10"
+ * in de-DE, "5 432,10" in fr-FR. Use for cert counts, agent counts,
+ * issuance rates, anything that's a count or a non-byte/non-percent
+ * scalar.
+ */
+const numberFmt = new Intl.NumberFormat(undefined, {
+  maximumFractionDigits: 2,
+});
+
+/**
+ * Compact / abbreviated formatter — "5.4K", "1.2M". Use for stat tiles
+ * where vertical space is constrained and ballpark magnitude beats
+ * exact value. Intl.NumberFormat's `notation: 'compact'` follows
+ * locale conventions (English K/M/B vs CJK 万/億 etc.) automatically.
+ */
+const compactFmt = new Intl.NumberFormat(undefined, {
+  notation: 'compact',
+  maximumFractionDigits: 1,
+});
+
+/**
+ * Percent formatter — input is a fraction in [0, 1] OR an explicit
+ * percentage with `style: 'percent'` semantics. We default to "input
+ * is a fraction" because that's the common case for success-rate /
+ * error-rate / etc. Output: "99.5%" (en) / "99,5 %" (fr).
+ */
+const percentFmt = new Intl.NumberFormat(undefined, {
+  style: 'percent',
+  minimumFractionDigits: 0,
+  maximumFractionDigits: 2,
+});
+
+/**
+ * Bytes formatter — Intl.NumberFormat with `style: 'unit'` and the
+ * byte unit. Output: "5.4 MB" (en) / "5,4 MB" (fr). Browser does the
+ * SI scaling automatically when given a base unit + value. For
+ * non-SI binary (KiB / MiB / GiB), use the manual scaler below.
+ *
+ * Note: Safari < 14 doesn't support the 'unit' style. The fallback
+ * branches produce "5.4 MB" without locale awareness; an operator on
+ * old Safari sees consistent-but-American output, which is the same
+ * graceful-degradation contract as the rest of the i18n boundary.
+ */
+const bytesFmt = (() => {
+  try {
+    return new Intl.NumberFormat(undefined, {
+      style: 'unit',
+      unit: 'megabyte',
+      maximumFractionDigits: 1,
+    });
+  } catch {
+    return null; // signals fallback
+  }
+})();
+
+/** Format an integer or decimal in the operator's locale. */
+export function formatNumber(value: number): string {
+  if (!Number.isFinite(value)) return '—';
+  return numberFmt.format(value);
+}
+
+/**
+ * Compact-format a magnitude — 1500 → "1.5K", 1_500_000 → "1.5M".
+ * Use for tile labels + chart axis ticks.
+ */
+export function formatCompact(value: number): string {
+  if (!Number.isFinite(value)) return '—';
+  return compactFmt.format(value);
+}
+
+/**
+ * Format a fraction in [0, 1] as a percentage. Pass 0.995 → "99.5%".
+ * For an already-percentified value (e.g. server returns 99.5 not
+ * 0.995), divide by 100 at the call site.
+ */
+export function formatPercent(value: number): string {
+  if (!Number.isFinite(value)) return '—';
+  return percentFmt.format(value);
+}
+
+/**
+ * Format a byte count with SI-decimal scaling (1KB = 1000B). Output
+ * locale-aware where possible; falls back to "5.4 MB"-style English
+ * on old Safari (see bytesFmt comment above).
+ *
+ * For binary scaling (1KiB = 1024B) use formatBytesBinary — relevant
+ * for memory / disk numbers that surface in Observability tiles.
+ */
+export function formatBytes(value: number): string {
+  if (!Number.isFinite(value)) return '—';
+  const { magnitude, unit } = pickSIUnit(value);
+  const scaled = value / magnitude;
+  if (bytesFmt) {
+    // Intl.NumberFormat doesn't accept the unit dynamically post-
+    // construction — we'd need a per-unit cache for that. Simpler:
+    // format the scaled magnitude with the standard number formatter
+    // and append the unit. Locale-aware decimal separator + space.
+    return `${numberFmt.format(round1(scaled))} ${unit}`;
+  }
+  return `${round1(scaled)} ${unit}`;
+}
+
+function pickSIUnit(bytes: number): { magnitude: number; unit: string } {
+  const abs = Math.abs(bytes);
+  if (abs >= 1e12) return { magnitude: 1e12, unit: 'TB' };
+  if (abs >= 1e9)  return { magnitude: 1e9,  unit: 'GB' };
+  if (abs >= 1e6)  return { magnitude: 1e6,  unit: 'MB' };
+  if (abs >= 1e3)  return { magnitude: 1e3,  unit: 'KB' };
+  return { magnitude: 1, unit: 'B' };
+}
+
+function round1(v: number): number {
+  return Math.round(v * 10) / 10;
+}
@@ -0,0 +1,75 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// queryConstants — the TanStack Query staleTime / gcTime tier model.
+// Phase 2 closure for TQ-M2 (twelve inconsistent staleTime override
+// values 15s–5min with no governing principle) + TQ-M1 (zero gcTime
+// overrides; 5-min default holds stale data across 87 pages of nav).
+//
+// Tier model
+// ==========
+// staleTime answers: "how long can the cached value be served as-is
+// without firing a background refetch?". Three tiers:
+//
+//   REAL_TIME    15s   — data that needs to look live for an operator
+//                        watching a workflow finish: in-flight jobs,
+//                        running agent heartbeats, scan progress,
+//                        certs-by-status. Refetch on window focus.
+//   REFERENCE     5min  — list endpoints + reference data: issuers,
+//                        profiles, owners, teams, agent groups,
+//                        certificate listings, audit log. The dominant
+//                        case in the codebase. No window-focus refetch.
+//   CONSTANT     1hr   — server-side metadata that's effectively
+//                        immutable in a normal session: OpenAPI spec,
+//                        version metadata, permission catalogue,
+//                        RBAC role list.
+//
+// gcTime answers: "how long should the cached value linger after
+// every observer unmounts before garbage-collection?". Three tiers:
+//
+//   HEAVY         1min — large payloads that pile up memory if held
+//                        long after the consumer page closed
+//                        (certificate listings, audit-log pages,
+//                        chart-data series).
+//   STANDARD      5min — the default for normal pages — held long
+//                        enough that revisits within a typical
+//                        workflow get an instant cache hit, but not
+//                        so long that the user's tab balloons.
+//   REFERENCE   30min — small, reusable data fetched on most pages
+//                        (RBAC catalogue, issuer/profile dropdown
+//                        options). Holding 30 min means the operator
+//                        navigating between Certificates / Targets /
+//                        Profiles / Issuers gets the same dropdown
+//                        cache without re-fetching.
+//
+// Migration policy: every new useQuery should pick ONE staleTime tier
+// + ONE gcTime tier. Bare numeric values are forbidden; the rg-based
+// CI guard will flag any new `staleTime:` not followed by
+// `STALE_TIME.` and `gcTime:` not followed by `GC_TIME.`.
+
+// staleTime — how long the cached value is "fresh" (no background refetch).
+export const STALE_TIME = {
+  /** 15s — live tile data (in-flight jobs, agent heartbeats, scan progress). */
+  REAL_TIME:   15_000,
+  /** 5min — list endpoints + reference data. The dominant case. */
+  REFERENCE:   5 * 60_000,
+  /** 1hr — effectively immutable in a normal session (catalogues, metadata). */
+  CONSTANT:    60 * 60_000,
+} as const;
+
+// gcTime — how long the cached value lingers after every observer unmounts.
+export const GC_TIME = {
+  /** 1min — large payloads (cert listings, audit pages, chart series). */
+  HEAVY:       60_000,
+  /** 5min — the normal-page default. */
+  STANDARD:    5 * 60_000,
+  /** 30min — small reusable dropdown / catalogue data. */
+  REFERENCE:   30 * 60_000,
+} as const;
+
+// Convenience exports for the explicit tier names — useful when the
+// caller wants to log the tier alongside the actual ms value (TanStack
+// Devtools prints the millisecond integer; this lets you cross-ref
+// the symbolic name).
+export type StaleTimeTier = keyof typeof STALE_TIME;
+export type GcTimeTier = keyof typeof GC_TIME;
@@ -0,0 +1,58 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Operator timestamp-display preference — Phase 6 closure for I18N-H3.
+//
+// Default: 'utc' (frontend display ≡ server audit log byte-for-byte).
+// Operators who prefer their local time explicitly opt in; operators
+// running across timezones (e.g. an EU admin watching a US-East server)
+// can pick a Custom IANA timezone.
+//
+// Storage: localStorage. No backend round-trip — the preference is
+// purely cosmetic + per-browser. If the operator clears storage they
+// reset to the safe default.
+
+const STORAGE_KEY = 'certctl:timestamp-display';
+
+export type TimestampMode = 'utc' | 'local' | 'custom';
+
+export interface TimestampPref {
+  mode: TimestampMode;
+  /** Only meaningful when mode === 'custom'. IANA TZ name, e.g. 'America/New_York'. */
+  customTz: string;
+}
+
+const DEFAULT: TimestampPref = { mode: 'utc', customTz: 'UTC' };
+
+/** Read the current preference. Always returns a valid value (defaults on parse/missing). */
+export function getTimestampPref(): TimestampPref {
+  if (typeof localStorage === 'undefined') return DEFAULT;
+  try {
+    const raw = localStorage.getItem(STORAGE_KEY);
+    if (!raw) return DEFAULT;
+    const parsed = JSON.parse(raw) as Partial<TimestampPref>;
+    if (parsed.mode !== 'utc' && parsed.mode !== 'local' && parsed.mode !== 'custom') {
+      return DEFAULT;
+    }
+    return {
+      mode: parsed.mode,
+      customTz: typeof parsed.customTz === 'string' && parsed.customTz.length > 0
+        ? parsed.customTz
+        : DEFAULT.customTz,
+    };
+  } catch {
+    return DEFAULT;
+  }
+}
+
+/** Write the preference. Silently no-ops if storage unavailable (e.g. private mode). */
+export function setTimestampPref(pref: TimestampPref): void {
+  if (typeof localStorage === 'undefined') return;
+  try {
+    localStorage.setItem(STORAGE_KEY, JSON.stringify(pref));
+    // Fire a custom event so live <Timestamp> components can re-render
+    // without a page reload. Vanilla CustomEvent — works in every
+    // browser certctl supports.
+    window.dispatchEvent(new CustomEvent('certctl:timestamp-pref-changed', { detail: pref }));
+  } catch { /* noop */ }
+}
@@ -1,11 +1,95 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Date / time / display helpers — the i18n-ready boundary the rest of
+// the frontend consumes. Phase 6 closure for I18N-H1 + I18N-H2 + I18N-H3.
+//
+// Locale handling:
+//   • Pre-Phase-6 these helpers hardcoded `'en-US'`, so a German /
+//     French / Japanese operator saw English month names regardless
+//     of their browser locale.
+//   • Post-Phase-6 we pass `undefined` for the locale arg, which makes
+//     the runtime use the browser default (navigator.language). The
+//     options object stays — `month: 'short'` etc. — so the SHAPE of
+//     the output is stable across locales while the language follows
+//     the user.
+//   • When a hard i18n framework lands (Phase 10), this file is the
+//     single migration target. Display code never reaches for
+//     Date.prototype.toLocaleString directly any more — Phase 6's CI
+//     guard at scripts/ci-guards/no-raw-toLocaleString.sh prevents
+//     regression.
+//
+// Timezone handling (I18N-H3):
+//   • formatDate / formatDateTime use the runtime's local timezone —
+//     keeps the existing operator-friendly default.
+//   • formatDateUTC / formatDateTimeUTC are explicit-UTC siblings.
+//     The audit-log table on the server emits UTC, so these helpers
+//     give the frontend a way to render the same byte-for-byte
+//     timestamp the operator sees in `journalctl -u certctl` or in a
+//     `psql` query.
+//   • <Timestamp iso={...} /> (web/src/components/Timestamp.tsx) wraps
+//     a UTC render in a Phase 1 Tooltip showing the operator-local
+//     equivalent. Default display is UTC (so screen ≡ logs); operators
+//     opt into local via the AuthSettingsPage "Timestamp display"
+//     preference.
+
+const DATE_OPTS: Intl.DateTimeFormatOptions = {
+  year: 'numeric',
+  month: 'short',
+  day: 'numeric',
+};
+
+const DATETIME_OPTS: Intl.DateTimeFormatOptions = {
+  year: 'numeric',
+  month: 'short',
+  day: 'numeric',
+  hour: '2-digit',
+  minute: '2-digit',
+};
+
+/** Format an ISO timestamp as a date in the browser's local timezone. */
 export function formatDate(iso: string | undefined | null): string {
  if (!iso) return '—';
-  return new Date(iso).toLocaleDateString('en-US', { year: 'numeric', month: 'short', day: 'numeric' });
+  // `undefined` for the locale arg = use the browser default
+  // (navigator.language). DO NOT hardcode 'en-US' here — that was
+  // the I18N-H1 bug Phase 6 closes.
+  return new Date(iso).toLocaleDateString(undefined, DATE_OPTS);
 }

+/** Format an ISO timestamp as a date+time in the browser's local timezone. */
 export function formatDateTime(iso: string | undefined | null): string {
  if (!iso) return '—';
-  return new Date(iso).toLocaleString('en-US', { year: 'numeric', month: 'short', day: 'numeric', hour: '2-digit', minute: '2-digit' });
+  return new Date(iso).toLocaleString(undefined, DATETIME_OPTS);
+}
+
+/** Format an ISO timestamp as a date forced to UTC. */
+export function formatDateUTC(iso: string | undefined | null): string {
+  if (!iso) return '—';
+  return new Date(iso).toLocaleDateString(undefined, { ...DATE_OPTS, timeZone: 'UTC' });
+}
+
+/**
+ * Format an ISO timestamp as a date+time forced to UTC.
+ * Matches the format certctl-server emits to journalctl + audit_events.
+ * Operator can cross-reference frontend display ≡ server log byte-for-byte.
+ */
+export function formatDateTimeUTC(iso: string | undefined | null): string {
+  if (!iso) return '—';
+  return new Date(iso).toLocaleString(undefined, { ...DATETIME_OPTS, timeZone: 'UTC' });
+}
+
+/**
+ * Format an ISO timestamp in an operator-specified timezone (IANA TZ name).
+ * Used by <Timestamp /> when the operator picks "Custom TZ" in settings.
+ * Falls back to UTC if the timezone name is invalid (Intl throws RangeError).
+ */
+export function formatDateTimeInZone(iso: string | undefined | null, timeZone: string): string {
+  if (!iso) return '—';
+  try {
+    return new Date(iso).toLocaleString(undefined, { ...DATETIME_OPTS, timeZone });
+  } catch {
+    return new Date(iso).toLocaleString(undefined, { ...DATETIME_OPTS, timeZone: 'UTC' });
+  }
 }

 // D-2 (master): widened to accept undefined/null since several Go-side
@@ -0,0 +1,66 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+
+import { render, screen, fireEvent } from '@testing-library/react';
+import { describe, it, expect, vi } from 'vitest';
+import Banner from './Banner';
+
+describe('Banner', () => {
+  it('renders the children', () => {
+    render(<Banner type="info">Operator note</Banner>);
+    expect(screen.getByText('Operator note')).toBeInTheDocument();
+  });
+
+  it('renders the optional title', () => {
+    render(
+      <Banner type="error" title="Save failed">
+        Permission denied.
+      </Banner>,
+    );
+    expect(screen.getByText('Save failed')).toBeInTheDocument();
+    expect(screen.getByText('Permission denied.')).toBeInTheDocument();
+  });
+
+  it('uses role="alert" for error variant', () => {
+    render(<Banner type="error">Permission denied.</Banner>);
+    expect(screen.getByRole('alert')).toBeInTheDocument();
+  });
+
+  it('uses role="alert" for warning variant', () => {
+    render(<Banner type="warning">Stale data.</Banner>);
+    expect(screen.getByRole('alert')).toBeInTheDocument();
+  });
+
+  it('uses role="status" for success variant', () => {
+    render(<Banner type="success">Saved.</Banner>);
+    expect(screen.getByRole('status')).toBeInTheDocument();
+  });
+
+  it('uses role="status" for info variant', () => {
+    render(<Banner type="info">Heads up.</Banner>);
+    expect(screen.getByRole('status')).toBeInTheDocument();
+  });
+
+  it('applies variant-specific bg + border classes', () => {
+    const { container } = render(<Banner type="error">err</Banner>);
+    const root = container.firstChild as HTMLElement;
+    expect(root.className).toContain('bg-red-50');
+    expect(root.className).toContain('border-red-200');
+  });
+
+  it('hides dismiss button when onDismiss not supplied', () => {
+    render(<Banner type="info">No close affordance.</Banner>);
+    expect(screen.queryByRole('button', { name: /dismiss/i })).toBeNull();
+  });
+
+  it('renders dismiss button + fires onDismiss when supplied', () => {
+    const onDismiss = vi.fn();
+    render(
+      <Banner type="info" onDismiss={onDismiss}>
+        Closable.
+      </Banner>,
+    );
+    fireEvent.click(screen.getByRole('button', { name: /dismiss/i }));
+    expect(onDismiss).toHaveBeenCalledTimes(1);
+  });
+});
@@ -0,0 +1,87 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Banner — the certctl-themed alert / message banner primitive. Phase 1
+// closure for FE-M4 (no banner primitives; ~102 inline
+// bg-(red|amber|yellow)-50 copy-paste sites across the codebase).
+//
+// Four severity variants:
+//   - error   red surface, role="alert"          — operator action required
+//   - warning amber surface, role="alert"        — risky-but-not-fatal
+//   - success teal surface, role="status"        — confirmation of last action
+//   - info    blue surface, role="status"        — neutral context
+//
+// role="alert" on error + warning surfaces these to screen readers
+// immediately on render (aria-live=assertive equivalent). role="status"
+// on success + info surfaces them politely (aria-live=polite).
+//
+// Optional `onDismiss` adds a close button — useful for transient
+// banners. Persistent banners (e.g. "TLS bootstrap incomplete") omit
+// it so the operator can't paper over the underlying state.
+
+import type { ReactNode } from 'react';
+
+export type BannerType = 'error' | 'warning' | 'success' | 'info';
+
+export interface BannerProps {
+  type: BannerType;
+  title?: string;
+  children: ReactNode;
+  onDismiss?: () => void;
+  className?: string;
+}
+
+const variantStyles: Record<BannerType, string> = {
+  error:   'bg-red-50    border-red-200    text-red-800',
+  warning: 'bg-amber-50  border-amber-200  text-amber-800',
+  success: 'bg-emerald-50 border-emerald-200 text-emerald-800',
+  info:    'bg-blue-50   border-blue-200   text-blue-800',
+};
+
+const variantTitleStyles: Record<BannerType, string> = {
+  error:   'text-red-900',
+  warning: 'text-amber-900',
+  success: 'text-emerald-900',
+  info:    'text-blue-900',
+};
+
+export default function Banner({
+  type,
+  title,
+  children,
+  onDismiss,
+  className = '',
+}: BannerProps) {
+  // role="alert" announces immediately; role="status" announces politely.
+  // Use alert for actionable / dangerous; status for confirmation /
+  // background context.
+  const role = type === 'error' || type === 'warning' ? 'alert' : 'status';
+
+  return (
+    <div
+      role={role}
+      className={`border-l-4 p-3 rounded ${variantStyles[type]} ${className}`}
+    >
+      <div className="flex items-start gap-3">
+        <div className="flex-1 text-sm">
+          {title && (
+            <div className={`font-semibold mb-0.5 ${variantTitleStyles[type]}`}>
+              {title}
+            </div>
+          )}
+          <div>{children}</div>
+        </div>
+        {onDismiss && (
+          <button
+            type="button"
+            onClick={onDismiss}
+            aria-label="Dismiss"
+            className={`text-xl leading-none opacity-60 hover:opacity-100 transition-opacity ${variantTitleStyles[type]}`}
+          >
+            ×
+          </button>
+        )}
+      </div>
+    </div>
+  );
+}
@@ -0,0 +1,93 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Breadcrumbs tests — Phase 3 UX-M5 closure.
+// Verifies the useLocation()-driven segment-walker:
+//   (a) root path "/" → no crumbs rendered (no empty <nav>)
+//   (b) top-level paths → Home + that page
+//   (c) detail paths → Home + List + Detail
+//   (d) deeply-nested /issuers/:id/hierarchy → Home + Issuers + Detail + Hierarchy
+//   (e) /auth/ subtree → uses authSubsegmentLabels
+//   (f) terminal crumb has aria-current="page" and is plain text;
+//       intermediate crumbs are <Link>s
+
+import { describe, it, expect } from 'vitest';
+import { render, screen } from '@testing-library/react';
+import { MemoryRouter } from 'react-router-dom';
+import Breadcrumbs from './Breadcrumbs';
+
+function renderAt(pathname: string) {
+  return render(
+    <MemoryRouter initialEntries={[pathname]}>
+      <Breadcrumbs />
+    </MemoryRouter>,
+  );
+}
+
+describe('Breadcrumbs', () => {
+  it('renders nothing for the dashboard root', () => {
+    const { container } = renderAt('/');
+    expect(container.querySelector('nav')).toBeNull();
+  });
+
+  it('renders Home + Certificates for /certificates', () => {
+    renderAt('/certificates');
+    expect(screen.getByText('Home')).toBeInTheDocument();
+    expect(screen.getByText('Certificates')).toBeInTheDocument();
+    const items = document.querySelectorAll('nav[aria-label="Breadcrumb"] ol > li');
+    expect(items.length).toBe(2);
+  });
+
+  it('renders Home + Certificates + Detail for /certificates/cert-001', () => {
+    renderAt('/certificates/cert-001');
+    expect(screen.getByText('Home')).toBeInTheDocument();
+    expect(screen.getByText('Certificates')).toBeInTheDocument();
+    expect(screen.getByText('Detail')).toBeInTheDocument();
+  });
+
+  it('walks /issuers/:id/hierarchy down to the Hierarchy leaf', () => {
+    renderAt('/issuers/iss-vault/hierarchy');
+    expect(screen.getByText('Home')).toBeInTheDocument();
+    expect(screen.getByText('Issuers')).toBeInTheDocument();
+    expect(screen.getByText('Detail')).toBeInTheDocument();
+    expect(screen.getByText('Hierarchy')).toBeInTheDocument();
+    // Hierarchy is the terminal crumb — plain text, aria-current.
+    const hierarchy = screen.getByText('Hierarchy');
+    expect(hierarchy.tagName).toBe('SPAN');
+    expect(hierarchy).toHaveAttribute('aria-current', 'page');
+  });
+
+  it('uses authSubsegmentLabels for /auth/* paths', () => {
+    renderAt('/auth/oidc/providers');
+    expect(screen.getByText('Access')).toBeInTheDocument();
+    expect(screen.getByText('OIDC')).toBeInTheDocument();
+    expect(screen.getByText('Providers')).toBeInTheDocument();
+  });
+
+  it("renders the last crumb as aria-current='page' plain text", () => {
+    renderAt('/certificates/cert-001');
+    const detail = screen.getByText('Detail');
+    expect(detail.tagName).toBe('SPAN');
+    expect(detail).toHaveAttribute('aria-current', 'page');
+  });
+
+  it('renders intermediate crumbs as <Link> elements pointing at their pathname', () => {
+    renderAt('/certificates/cert-001');
+    const home = screen.getByText('Home');
+    const homeAnchor = home.closest('a');
+    expect(homeAnchor).not.toBeNull();
+    expect(homeAnchor!.getAttribute('href')).toBe('/');
+
+    const certs = screen.getByText('Certificates');
+    const certsAnchor = certs.closest('a');
+    expect(certsAnchor).not.toBeNull();
+    expect(certsAnchor!.getAttribute('href')).toBe('/certificates');
+  });
+
+  it('exposes nav[aria-label="Breadcrumb"] for screen readers', () => {
+    renderAt('/issuers');
+    expect(
+      screen.getByRole('navigation', { name: 'Breadcrumb' }),
+    ).toBeInTheDocument();
+  });
+});
@@ -0,0 +1,176 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Breadcrumbs — Phase 3 closure for UX-M5 (zero breadcrumb component,
+// zero navigate(-1), 3-deep routes like issuers/:id/hierarchy have no
+// wayfinding).
+//
+// Implementation note: the audit prompt suggested useMatches() + per-
+// route handle.crumb. That requires React Router v6's data-router
+// (createBrowserRouter), but the certctl app currently uses the JSX
+// <BrowserRouter> form. Migrating the router config is its own
+// phase-sized effort with non-trivial blast radius (every Route
+// element, every test's MemoryRouter wrapper). Instead, this version
+// uses useLocation() to read the current pathname + walks the
+// segments, mapping each one to a label via the static
+// pathSegmentLabels lookup below. Limitations: only the top-level +
+// detail-route segments get a label (anything matching /:id/.../ at a
+// depth > 2 falls back to the literal segment). Sufficient for the
+// 3-deep routes the audit flagged (e.g. /issuers/:id/hierarchy);
+// upgrading to data-router-driven crumbs is a future task once the
+// router migration ships.
+
+import { Link, useLocation, useInRouterContext } from 'react-router-dom';
+import { ChevronRight } from 'lucide-react';
+
+// pathSegmentLabels — map first-segment URL keys to human labels.
+// Add entries here as new top-level routes land. Lookup is exact-
+// match on the first path segment; subsequent segments are heuristics
+// (see crumbsFor below).
+const pathSegmentLabels: Record<string, string> = {
+  certificates:    'Certificates',
+  issuers:         'Issuers',
+  agents:          'Agents',
+  targets:         'Targets',
+  jobs:            'Jobs',
+  notifications:   'Notifications',
+  policies:        'Policies',
+  'renewal-policies': 'Renewal Policies',
+  profiles:        'Profiles',
+  owners:          'Owners',
+  teams:           'Teams',
+  'agent-groups':  'Agent Groups',
+  audit:           'Audit Trail',
+  'short-lived':   'Short-Lived',
+  fleet:           'Fleet Overview',
+  discovery:       'Discovery',
+  'network-scans': 'Network Scans',
+  'health-monitor': 'Health Monitor',
+  digest:          'Digest',
+  observability:   'Observability',
+  scep:            'SCEP Admin',
+  est:             'EST Admin',
+  auth:            'Access',
+};
+
+// Auth-subtree subsegments (e.g. /auth/oidc/providers).
+const authSubsegmentLabels: Record<string, string> = {
+  oidc:       'OIDC',
+  providers:  'Providers',
+  sessions:   'Sessions',
+  users:      'Users',
+  roles:      'Roles',
+  keys:       'API Keys',
+  approvals:  'Approvals',
+  breakglass: 'Break-glass',
+  settings:   'Auth Settings',
+};
+
+interface Crumb {
+  pathname: string;
+  label: string;
+  isLast: boolean;
+}
+
+function crumbsFor(pathname: string): Crumb[] {
+  // Dashboard root produces no breadcrumb trail — the title alone
+  // suffices.
+  if (pathname === '/' || pathname === '') return [];
+
+  const segments = pathname.split('/').filter(Boolean);
+  if (segments.length === 0) return [];
+
+  // The Dashboard ("Home") crumb is always the first hop.
+  const out: Crumb[] = [{ pathname: '/', label: 'Home', isLast: false }];
+
+  // First segment — top-level route.
+  const first = segments[0]!;
+  const firstLabel = pathSegmentLabels[first] ?? first;
+  out.push({
+    pathname: '/' + first,
+    label: firstLabel,
+    isLast: segments.length === 1,
+  });
+
+  // Subsequent segments — heuristics:
+  //   - /auth/<sub>[/...] uses authSubsegmentLabels for each piece
+  //   - any other segment that looks like an :id (starts with a
+  //     known prefix or is hex/random) becomes "Detail"
+  //   - terminal /hierarchy on /issuers/:id/hierarchy → "Hierarchy"
+  let acc = '/' + first;
+  for (let i = 1; i < segments.length; i++) {
+    const seg = segments[i]!;
+    acc += '/' + seg;
+    let label: string;
+    if (first === 'auth') {
+      label = authSubsegmentLabels[seg] ?? seg;
+    } else if (seg === 'hierarchy') {
+      label = 'Hierarchy';
+    } else if (looksLikeID(seg)) {
+      label = 'Detail';
+    } else {
+      label = seg;
+    }
+    out.push({ pathname: acc, label, isLast: i === segments.length - 1 });
+  }
+
+  return out;
+}
+
+/** ID-shape heuristic — certctl IDs look like cert-001, iss-vault, t-iis-prod. */
+function looksLikeID(s: string): boolean {
+  // Anything with a hyphen is treated as an ID for breadcrumb purposes.
+  // Hyphenated segments that aren't IDs (renewal-policies, agent-groups,
+  // network-scans, health-monitor, short-lived) are top-level routes
+  // resolved by pathSegmentLabels BEFORE this heuristic fires.
+  return s.includes('-') || /^[a-f0-9]{8,}$/i.test(s);
+}
+
+// Breadcrumbs is the public entry. Defensive against missing Router
+// context (a test that mounts a PageHeader without a <MemoryRouter>
+// wrapper used to crash here). useLocation() throws an invariant
+// error if there's no Router; gate it behind useInRouterContext()
+// + render the actual logic in a sibling so useLocation() is only
+// called when we know the context is present.
+export default function Breadcrumbs() {
+  const inRouter = useInRouterContext();
+  if (!inRouter) return null;
+  return <BreadcrumbsInner />;
+}
+
+function BreadcrumbsInner() {
+  const { pathname } = useLocation();
+  const crumbs = crumbsFor(pathname);
+
+  if (crumbs.length === 0) return null;
+
+  return (
+    <nav aria-label="Breadcrumb" className="mb-1">
+      <ol className="flex items-center gap-1 text-xs text-ink-muted">
+        {crumbs.map((c, i) => (
+          <li key={c.pathname} className="flex items-center gap-1">
+            {i > 0 && (
+              <ChevronRight
+                className="w-3 h-3 text-ink-faint shrink-0"
+                strokeWidth={1.5}
+                aria-hidden="true"
+              />
+            )}
+            {c.isLast ? (
+              <span aria-current="page" className="text-ink font-medium">
+                {c.label}
+              </span>
+            ) : (
+              <Link
+                to={c.pathname}
+                className="hover:text-brand-500 hover:underline transition-colors"
+              >
+                {c.label}
+              </Link>
+            )}
+          </li>
+        ))}
+      </ol>
+    </nav>
+  );
+}
@@ -0,0 +1,100 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+
+import { render, screen, fireEvent } from '@testing-library/react';
+import { describe, it, expect, vi } from 'vitest';
+import Combobox from './Combobox';
+
+type Option = { id: string; name: string };
+
+const OPTIONS: Option[] = [
+  { id: 'iss-vault', name: 'Vault PKI' },
+  { id: 'iss-acme',  name: 'ACME (Let\'s Encrypt)' },
+  { id: 'iss-local', name: 'Local CA' },
+];
+
+describe('Combobox', () => {
+  it('renders the input', () => {
+    render(
+      <Combobox<Option>
+        value={null}
+        onChange={() => {}}
+        options={OPTIONS}
+        getKey={(o) => o.id}
+        getLabel={(o) => o.name}
+        placeholder="Pick issuer"
+      />,
+    );
+    expect(screen.getByPlaceholderText('Pick issuer')).toBeInTheDocument();
+  });
+
+  it('renders the selected value as the input display', () => {
+    render(
+      <Combobox<Option>
+        value={OPTIONS[2]}
+        onChange={() => {}}
+        options={OPTIONS}
+        getKey={(o) => o.id}
+        getLabel={(o) => o.name}
+      />,
+    );
+    expect(screen.getByDisplayValue('Local CA')).toBeInTheDocument();
+  });
+
+  it('filters options as the operator types', () => {
+    render(
+      <Combobox<Option>
+        value={null}
+        onChange={() => {}}
+        options={OPTIONS}
+        getKey={(o) => o.id}
+        getLabel={(o) => o.name}
+      />,
+    );
+    const input = screen.getByRole('combobox');
+    fireEvent.change(input, { target: { value: 'vault' } });
+    expect(screen.getByText('Vault PKI')).toBeInTheDocument();
+    expect(screen.queryByText('Local CA')).not.toBeInTheDocument();
+    expect(screen.queryByText("ACME (Let's Encrypt)")).not.toBeInTheDocument();
+  });
+
+  it('fires onChange when the operator selects via keyboard', () => {
+    const onChange = vi.fn();
+    render(
+      <Combobox<Option>
+        value={null}
+        onChange={onChange}
+        options={OPTIONS}
+        getKey={(o) => o.id}
+        getLabel={(o) => o.name}
+      />,
+    );
+    // Open the listbox + filter to a single option, then press Enter.
+    // Click-to-select on Headless UI requires the pointerdown sequence
+    // which @testing-library/dom's fireEvent doesn't synthesize; the
+    // keyboard path is the accessible-equivalent and is what screen
+    // reader / keyboard-only operators use anyway.
+    const input = screen.getByRole('combobox');
+    fireEvent.focus(input);
+    fireEvent.change(input, { target: { value: 'Local' } });
+    fireEvent.keyDown(input, { key: 'ArrowDown' });
+    fireEvent.keyDown(input, { key: 'Enter' });
+    expect(onChange).toHaveBeenCalledWith(OPTIONS[2]);
+  });
+
+  it('shows "No matches" when the filter excludes everything', () => {
+    render(
+      <Combobox<Option>
+        value={null}
+        onChange={() => {}}
+        options={OPTIONS}
+        getKey={(o) => o.id}
+        getLabel={(o) => o.name}
+      />,
+    );
+    const input = screen.getByRole('combobox');
+    fireEvent.focus(input);
+    fireEvent.change(input, { target: { value: 'nonexistent' } });
+    expect(screen.getByText('No matches.')).toBeInTheDocument();
+  });
+});
@@ -0,0 +1,104 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Combobox — Headless UI-backed typeahead select primitive. Phase 1
+// closure for UX-M4 (~53 native HTML <select> elements with no
+// typeahead surface). Migrating callsites is per-page rolling work
+// in subsequent PRs; Phase 1 builds the primitive.
+//
+// Compared with native <select>:
+//   - typeahead filter narrows options as the operator types
+//   - keyboard nav (Up/Down/Enter/Esc) handled by Headless UI
+//   - aria-expanded / aria-activedescendant / aria-labelledby wired
+//     for free
+//   - styled to match the certctl .input + .card token palette
+//
+// Generic on the option value type T (string IDs are typical; arbitrary
+// objects work too — supply a `getKey` + `getLabel`).
+
+import { useState, useMemo } from 'react';
+import { Combobox as HeadlessCombobox } from '@headlessui/react';
+
+export interface ComboboxProps<T> {
+  /** The currently-selected option, or null if none. */
+  value: T | null;
+  /** Fires when the operator picks an option. */
+  onChange: (next: T | null) => void;
+  /** Full options list — Combobox filters internally on typed query. */
+  options: T[];
+  /** Stable string key per option (used for React `key` + filter equality). */
+  getKey: (option: T) => string;
+  /** Human-readable label rendered in the input + dropdown row. */
+  getLabel: (option: T) => string;
+  /** Optional placeholder when no value is selected. */
+  placeholder?: string;
+  /** Optional `id` on the input element (label wiring). */
+  inputId?: string;
+  /** Disabled state. */
+  disabled?: boolean;
+  /** Extra className on the outer wrapper. */
+  className?: string;
+}
+
+export default function Combobox<T>({
+  value,
+  onChange,
+  options,
+  getKey,
+  getLabel,
+  placeholder,
+  inputId,
+  disabled,
+  className = '',
+}: ComboboxProps<T>) {
+  const [query, setQuery] = useState('');
+
+  // Filter is local + case-insensitive substring against the label.
+  // For >1000-option lists this should move to server-side; not Phase
+  // 1's problem.
+  const filtered = useMemo(() => {
+    if (!query) return options;
+    const needle = query.toLowerCase();
+    return options.filter((o) => getLabel(o).toLowerCase().includes(needle));
+  }, [options, query, getLabel]);
+
+  return (
+    <HeadlessCombobox
+      value={value}
+      onChange={onChange}
+      disabled={disabled}
+    >
+      <div className={`relative ${className}`}>
+        <HeadlessCombobox.Input
+          id={inputId}
+          className="input w-full"
+          placeholder={placeholder}
+          displayValue={(o: T | null) => (o ? getLabel(o) : '')}
+          onChange={(e) => setQuery(e.target.value)}
+        />
+        <HeadlessCombobox.Options
+          className="absolute z-30 mt-1 max-h-60 w-full overflow-auto rounded border border-surface-border bg-surface shadow-lg focus:outline-none"
+        >
+          {filtered.length === 0 && query !== '' && (
+            <div className="px-3 py-2 text-sm text-ink-faint">
+              No matches.
+            </div>
+          )}
+          {filtered.map((option) => (
+            <HeadlessCombobox.Option
+              key={getKey(option)}
+              value={option}
+              className={({ active, selected }) =>
+                `cursor-pointer px-3 py-2 text-sm ${
+                  active ? 'bg-brand-50 text-brand-700' : 'text-ink'
+                } ${selected ? 'font-semibold' : ''}`
+              }
+            >
+              {getLabel(option)}
+            </HeadlessCombobox.Option>
+          ))}
+        </HeadlessCombobox.Options>
+      </div>
+    </HeadlessCombobox>
+  );
+}
@@ -0,0 +1,287 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// CommandPalette — Phase 3 closure for UX-H6 (no cmd+k palette, no
+// <input type="search">, no global keyboard-shortcut surface) and
+// FE-L4 (rolls under UX-H6 per the audit's framing).
+//
+// Built on `cmdk`. Three sections:
+//
+//   1. Navigation — every route surfaced in Layout.tsx's navGroups.
+//      Operator types "audit", picks the matching row, navigates to
+//      /audit. Reproduces a sidebar without the scroll.
+//   2. Actions — quick-fire operations that aren't routes: "Issue
+//      new certificate" (navigates to / + ?onboarding=1), "Create
+//      issuer", "Trigger discovery scan". Each action is a callback
+//      that closes the palette.
+//   3. Server-search — debounced fetch against /api/v1/certificates?q=
+//      + /api/v1/issuers?q= for typeahead across cert names + issuer
+//      names. Results stream into the same cmdk list under a "Search
+//      results" heading; clicking jumps to that record's detail page.
+//
+// Global keydown listener (meta+k on macOS, ctrl+k everywhere else)
+// is wired in web/src/main.tsx — the palette itself is render-only
+// and reads `open` from a prop.
+
+import { Command } from 'cmdk';
+import { useEffect, useMemo, useState } from 'react';
+import { useNavigate } from 'react-router-dom';
+import {
+  LayoutDashboard, ShieldCheck, Search, Server, Network, Radar, Timer,
+  KeyRound, FileText, ScrollText, RefreshCw, Wrench,
+  Target, ListTodo, HeartPulse,
+  User, Users, Group,
+  Bell, Inbox, Activity,
+  Clock, UserCog, CheckCircle2, AlertTriangle, Cog,
+  Plus, Zap,
+} from 'lucide-react';
+import type { LucideIcon } from 'lucide-react';
+import { getCertificates, getIssuers } from '../api/client';
+import type { Certificate, Issuer } from '../api/types';
+
+export interface CommandPaletteProps {
+  open: boolean;
+  onOpenChange: (open: boolean) => void;
+}
+
+interface NavCommand {
+  to: string;
+  label: string;
+  group: string;
+  icon: LucideIcon;
+}
+
+// NAV_COMMANDS — flattened view of Layout.tsx's navGroups, kept in
+// sync by hand. (DRY-ing this against the Layout would require an
+// extra module just to share the table; the audit notes future work
+// could collapse them.)
+const NAV_COMMANDS: NavCommand[] = [
+  // Inventory
+  { to: '/',               label: 'Dashboard',       group: 'Inventory', icon: LayoutDashboard },
+  { to: '/certificates',   label: 'Certificates',    group: 'Inventory', icon: ShieldCheck },
+  { to: '/discovery',      label: 'Discovery',       group: 'Inventory', icon: Search },
+  { to: '/agents',         label: 'Agents',          group: 'Inventory', icon: Server },
+  { to: '/fleet',          label: 'Fleet Overview',  group: 'Inventory', icon: Network },
+  { to: '/network-scans',  label: 'Network Scans',   group: 'Inventory', icon: Radar },
+  { to: '/short-lived',    label: 'Short-Lived',     group: 'Inventory', icon: Timer },
+  // Trust
+  { to: '/issuers',          label: 'Issuers',          group: 'Trust', icon: KeyRound },
+  { to: '/profiles',         label: 'Profiles',         group: 'Trust', icon: FileText },
+  { to: '/policies',         label: 'Policies',         group: 'Trust', icon: ScrollText },
+  { to: '/renewal-policies', label: 'Renewal Policies', group: 'Trust', icon: RefreshCw },
+  { to: '/scep',             label: 'SCEP Admin',       group: 'Trust', icon: Wrench },
+  { to: '/est',              label: 'EST Admin',        group: 'Trust', icon: Wrench },
+  // Delivery
+  { to: '/targets',         label: 'Targets',        group: 'Delivery', icon: Target },
+  { to: '/jobs',            label: 'Jobs',           group: 'Delivery', icon: ListTodo },
+  { to: '/health-monitor',  label: 'Health Monitor', group: 'Delivery', icon: HeartPulse },
+  // People
+  { to: '/owners',       label: 'Owners',       group: 'People', icon: User },
+  { to: '/teams',        label: 'Teams',        group: 'People', icon: Users },
+  { to: '/agent-groups', label: 'Agent Groups', group: 'People', icon: Group },
+  // Notify
+  { to: '/notifications', label: 'Notifications', group: 'Notify', icon: Bell },
+  { to: '/digest',        label: 'Digest',        group: 'Notify', icon: Inbox },
+  { to: '/observability', label: 'Observability', group: 'Notify', icon: Activity },
+  // Access
+  { to: '/auth/oidc/providers', label: 'OIDC Providers', group: 'Access', icon: ShieldCheck },
+  { to: '/auth/sessions',       label: 'Sessions',       group: 'Access', icon: Clock },
+  { to: '/auth/users',          label: 'Users',          group: 'Access', icon: Users },
+  { to: '/auth/roles',          label: 'Roles',          group: 'Access', icon: UserCog },
+  { to: '/auth/keys',           label: 'API Keys',       group: 'Access', icon: KeyRound },
+  { to: '/auth/approvals',      label: 'Approvals',      group: 'Access', icon: CheckCircle2 },
+  { to: '/auth/breakglass',     label: 'Break-glass',    group: 'Access', icon: AlertTriangle },
+  { to: '/auth/settings',       label: 'Auth Settings',  group: 'Access', icon: Cog },
+  // Audit
+  { to: '/audit', label: 'Audit Trail', group: 'Audit', icon: ScrollText },
+];
+
+interface SearchResult {
+  type: 'certificate' | 'issuer';
+  id: string;
+  label: string;
+  to: string;
+}
+
+/**
+ * useDebouncedValue — small hook to throttle the server-search query
+ * so we don't fire a fetch on every keystroke.
+ */
+function useDebouncedValue<T>(value: T, ms: number): T {
+  const [debounced, setDebounced] = useState(value);
+  useEffect(() => {
+    const t = setTimeout(() => setDebounced(value), ms);
+    return () => clearTimeout(t);
+  }, [value, ms]);
+  return debounced;
+}
+
+export default function CommandPalette({ open, onOpenChange }: CommandPaletteProps) {
+  const navigate = useNavigate();
+  const [query, setQuery] = useState('');
+  const debouncedQuery = useDebouncedValue(query, 250);
+  const [serverResults, setServerResults] = useState<SearchResult[]>([]);
+
+  // Server-search on debounced input. Empty / <2-char queries skip
+  // the fetch (too many results to be useful + load on the API).
+  useEffect(() => {
+    if (!open || debouncedQuery.length < 2) {
+      setServerResults([]);
+      return;
+    }
+    let cancelled = false;
+    (async () => {
+      try {
+        const [certsResp, issuersResp] = await Promise.all([
+          getCertificates({ q: debouncedQuery, per_page: '8' }),
+          getIssuers({ q: debouncedQuery, per_page: '8' }),
+        ]);
+        if (cancelled) return;
+        const certs: SearchResult[] = (certsResp?.data ?? []).map((c: Certificate) => ({
+          type: 'certificate',
+          id: c.id,
+          label: c.common_name || c.id,
+          to: `/certificates/${c.id}`,
+        }));
+        const issuers: SearchResult[] = (issuersResp?.data ?? []).map((i: Issuer) => ({
+          type: 'issuer',
+          id: i.id,
+          label: i.name || i.id,
+          to: `/issuers/${i.id}`,
+        }));
+        setServerResults([...certs, ...issuers]);
+      } catch {
+        // Silent — keep whatever's already in the list.
+        if (!cancelled) setServerResults([]);
+      }
+    })();
+    return () => { cancelled = true; };
+  }, [debouncedQuery, open]);
+
+  // Reset query each time the palette opens — fresh state per session.
+  useEffect(() => {
+    if (open) setQuery('');
+  }, [open]);
+
+  const navByGroup = useMemo(() => {
+    const m = new Map<string, NavCommand[]>();
+    for (const n of NAV_COMMANDS) {
+      if (!m.has(n.group)) m.set(n.group, []);
+      m.get(n.group)!.push(n);
+    }
+    return m;
+  }, []);
+
+  const go = (to: string) => {
+    onOpenChange(false);
+    navigate(to);
+  };
+
+  if (!open) return null;
+
+  return (
+    <Command.Dialog
+      open={open}
+      onOpenChange={onOpenChange}
+      label="Global command palette"
+      className="fixed inset-0 z-50 flex items-start justify-center pt-24"
+    >
+      {/* Backdrop */}
+      <div
+        className="fixed inset-0 bg-black/40"
+        aria-hidden="true"
+        onClick={() => onOpenChange(false)}
+      />
+
+      {/* Panel */}
+      <div className="relative w-full max-w-xl bg-surface border border-surface-border rounded-lg shadow-2xl overflow-hidden">
+        <Command.Input
+          autoFocus
+          value={query}
+          onValueChange={setQuery}
+          placeholder="Type a page name, action, or search certs / issuers…"
+          className="w-full px-4 py-3 text-sm text-ink bg-transparent border-b border-surface-border focus:outline-none placeholder:text-ink-faint"
+        />
+        <Command.List className="max-h-96 overflow-y-auto py-1">
+          <Command.Empty className="px-4 py-6 text-center text-sm text-ink-faint">
+            No matches — try a different term.
+          </Command.Empty>
+
+          {/* Navigation — every sidebar item, grouped */}
+          {Array.from(navByGroup.entries()).map(([groupName, items]) => (
+            <Command.Group key={groupName} heading={groupName}>
+              {items.map((item) => {
+                const I = item.icon;
+                return (
+                  <Command.Item
+                    key={item.to}
+                    value={`${groupName} ${item.label}`}
+                    onSelect={() => go(item.to)}
+                    className="px-4 py-2 text-sm text-ink cursor-pointer flex items-center gap-3 data-[selected=true]:bg-brand-50 data-[selected=true]:text-brand-700"
+                  >
+                    <I className="w-4 h-4 shrink-0 text-ink-muted" strokeWidth={1.75} aria-hidden="true" />
+                    <span>{item.label}</span>
+                  </Command.Item>
+                );
+              })}
+            </Command.Group>
+          ))}
+
+          {/* Actions — quick-fire operations that aren't routes */}
+          <Command.Group heading="Actions">
+            <Command.Item
+              value="action issue new certificate"
+              onSelect={() => go('/?onboarding=1')}
+              className="px-4 py-2 text-sm text-ink cursor-pointer flex items-center gap-3 data-[selected=true]:bg-brand-50 data-[selected=true]:text-brand-700"
+            >
+              <Plus className="w-4 h-4 shrink-0 text-ink-muted" strokeWidth={1.75} aria-hidden="true" />
+              <span>Issue new certificate (Setup guide)</span>
+            </Command.Item>
+            <Command.Item
+              value="action create issuer"
+              onSelect={() => go('/issuers')}
+              className="px-4 py-2 text-sm text-ink cursor-pointer flex items-center gap-3 data-[selected=true]:bg-brand-50 data-[selected=true]:text-brand-700"
+            >
+              <KeyRound className="w-4 h-4 shrink-0 text-ink-muted" strokeWidth={1.75} aria-hidden="true" />
+              <span>Create issuer…</span>
+            </Command.Item>
+            <Command.Item
+              value="action trigger discovery scan"
+              onSelect={() => go('/network-scans')}
+              className="px-4 py-2 text-sm text-ink cursor-pointer flex items-center gap-3 data-[selected=true]:bg-brand-50 data-[selected=true]:text-brand-700"
+            >
+              <Zap className="w-4 h-4 shrink-0 text-ink-muted" strokeWidth={1.75} aria-hidden="true" />
+              <span>Trigger discovery scan…</span>
+            </Command.Item>
+          </Command.Group>
+
+          {/* Server search — only render the heading if we have hits */}
+          {serverResults.length > 0 && (
+            <Command.Group heading="Search results">
+              {serverResults.map((r) => (
+                <Command.Item
+                  key={`${r.type}-${r.id}`}
+                  value={`search ${r.label} ${r.id}`}
+                  onSelect={() => go(r.to)}
+                  className="px-4 py-2 text-sm text-ink cursor-pointer flex items-center gap-3 data-[selected=true]:bg-brand-50 data-[selected=true]:text-brand-700"
+                >
+                  {r.type === 'certificate'
+                    ? <ShieldCheck className="w-4 h-4 shrink-0 text-ink-muted" strokeWidth={1.75} aria-hidden="true" />
+                    : <KeyRound    className="w-4 h-4 shrink-0 text-ink-muted" strokeWidth={1.75} aria-hidden="true" />}
+                  <span className="flex-1">{r.label}</span>
+                  <span className="text-xs text-ink-faint capitalize">{r.type}</span>
+                </Command.Item>
+              ))}
+            </Command.Group>
+          )}
+        </Command.List>
+
+        {/* Footer hint */}
+        <div className="px-4 py-2 border-t border-surface-border text-xs text-ink-faint flex items-center justify-between">
+          <span>↑↓ navigate · ↵ select · esc close</span>
+          <span><kbd className="px-1 py-0.5 text-2xs bg-surface-muted border border-surface-border rounded">⌘K</kbd></span>
+        </div>
+      </div>
+    </Command.Dialog>
+  );
+}
@@ -0,0 +1,44 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// CommandPaletteHost — Phase 3 closure: thin wrapper around
+// CommandPalette that owns the open/close state + the global
+// keyboard listener (meta+k on mac, ctrl+k everywhere else).
+//
+// Lives at the React tree root (mounted alongside Toaster in
+// main.tsx) so the keydown handler is registered once + survives
+// page navigations. The handler is intentionally scoped to the
+// component lifecycle so HMR + React StrictMode double-mount don't
+// leave orphaned listeners.
+
+import { useEffect, useState, lazy, Suspense } from 'react';
+
+// Lazy-load the palette so cmdk's bundle (~25 KB) doesn't land on
+// the initial page load — only fetched once the operator hits cmd+k.
+const CommandPalette = lazy(() => import('./CommandPalette'));
+
+export default function CommandPaletteHost() {
+  const [open, setOpen] = useState(false);
+
+  useEffect(() => {
+    const handler = (e: KeyboardEvent) => {
+      // metaKey on macOS, ctrlKey on Windows / Linux.
+      const isCmdK = e.key === 'k' && (e.metaKey || e.ctrlKey);
+      if (isCmdK) {
+        e.preventDefault();
+        setOpen((prev) => !prev);
+      }
+    };
+    document.addEventListener('keydown', handler);
+    return () => document.removeEventListener('keydown', handler);
+  }, []);
+
+  // Only mount the palette tree when first-needed — avoids fetching
+  // cmdk's bundle on every page load.
+  if (!open) return null;
+  return (
+    <Suspense fallback={null}>
+      <CommandPalette open={open} onOpenChange={setOpen} />
+    </Suspense>
+  );
+}
@@ -0,0 +1,136 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Smoke + behavior tests for ConfirmDialog. The primitive replaces
+// window.confirm(); the test suite asserts the contract:
+//   - hidden when open=false
+//   - title + message render
+//   - ESC + backdrop click + cancel button → onCancel
+//   - confirm button → onConfirm
+//   - typedConfirmation gates the confirm button until the exact string
+//     is typed
+//   - destructive=true uses the btn-danger styling
+
+import { render, screen, fireEvent } from '@testing-library/react';
+import { describe, it, expect, vi } from 'vitest';
+import ConfirmDialog from './ConfirmDialog';
+
+describe('ConfirmDialog', () => {
+  it('does not render when open=false', () => {
+    render(
+      <ConfirmDialog
+        open={false}
+        title="Archive cert"
+        message="Cannot be undone."
+        onConfirm={() => {}}
+        onCancel={() => {}}
+      />,
+    );
+    expect(screen.queryByText('Archive cert')).not.toBeInTheDocument();
+  });
+
+  it('renders title + message when open=true', () => {
+    render(
+      <ConfirmDialog
+        open
+        title="Archive cert"
+        message="Cannot be undone."
+        onConfirm={() => {}}
+        onCancel={() => {}}
+      />,
+    );
+    expect(screen.getByText('Archive cert')).toBeInTheDocument();
+    expect(screen.getByText('Cannot be undone.')).toBeInTheDocument();
+  });
+
+  it('fires onConfirm when confirm button clicked', () => {
+    const onConfirm = vi.fn();
+    render(
+      <ConfirmDialog
+        open
+        title="Delete owner"
+        message="Bob will be removed."
+        onConfirm={onConfirm}
+        onCancel={() => {}}
+      />,
+    );
+    fireEvent.click(screen.getByRole('button', { name: /confirm/i }));
+    expect(onConfirm).toHaveBeenCalledTimes(1);
+  });
+
+  it('fires onCancel when cancel button clicked', () => {
+    const onCancel = vi.fn();
+    render(
+      <ConfirmDialog
+        open
+        title="Delete owner"
+        message="Bob will be removed."
+        onConfirm={() => {}}
+        onCancel={onCancel}
+      />,
+    );
+    fireEvent.click(screen.getByRole('button', { name: /cancel/i }));
+    expect(onCancel).toHaveBeenCalledTimes(1);
+  });
+
+  it('disables confirm button until typedConfirmation matches', () => {
+    const onConfirm = vi.fn();
+    render(
+      <ConfirmDialog
+        open
+        title="Archive cert"
+        message="Type DELETE to confirm."
+        typedConfirmation="DELETE"
+        onConfirm={onConfirm}
+        onCancel={() => {}}
+      />,
+    );
+    const confirmBtn = screen.getByRole('button', { name: /confirm/i });
+    expect(confirmBtn).toBeDisabled();
+
+    const input = screen.getByLabelText(/Type/i);
+    fireEvent.change(input, { target: { value: 'wrong' } });
+    expect(confirmBtn).toBeDisabled();
+
+    fireEvent.change(input, { target: { value: 'DELETE' } });
+    expect(confirmBtn).not.toBeDisabled();
+
+    fireEvent.click(confirmBtn);
+    expect(onConfirm).toHaveBeenCalledTimes(1);
+  });
+
+  it('uses btn-danger styling when destructive=true', () => {
+    render(
+      <ConfirmDialog
+        open
+        title="Revoke cert"
+        message="Cannot be undone."
+        destructive
+        onConfirm={() => {}}
+        onCancel={() => {}}
+      />,
+    );
+    const confirmBtn = screen.getByRole('button', { name: /confirm/i });
+    expect(confirmBtn.className).toContain('btn-danger');
+  });
+
+  it('honours custom confirmLabel + cancelLabel', () => {
+    render(
+      <ConfirmDialog
+        open
+        title="Archive cert"
+        message="Are you sure?"
+        confirmLabel="Yes, archive"
+        cancelLabel="No, go back"
+        onConfirm={() => {}}
+        onCancel={() => {}}
+      />,
+    );
+    expect(
+      screen.getByRole('button', { name: 'Yes, archive' }),
+    ).toBeInTheDocument();
+    expect(
+      screen.getByRole('button', { name: 'No, go back' }),
+    ).toBeInTheDocument();
+  });
+});
@@ -0,0 +1,181 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// ConfirmDialog — the certctl-themed replacement for window.confirm().
+// Phase 1 closure for UX-H2 (destructive actions use window.confirm).
+//
+// Built on Headless UI's <Dialog>, which gives us:
+//   - automatic focus trap (Tab/Shift-Tab stays inside the modal)
+//   - automatic ESC-to-close (we wire onCancel to it)
+//   - automatic backdrop-click-to-close (we wire onCancel to it)
+//   - role="dialog" + aria-modal="true" on the panel
+//   - aria-labelledby on the title node, aria-describedby on the body
+//   - <Transition> handles enter/exit; respects prefers-reduced-motion
+//     transparently via the @media block in src/index.css.
+//
+// Optional `typedConfirmation` raises the friction for the most
+// irreversible actions. Passing `typedConfirmation: "delete"` requires
+// the operator to literally type the string "delete" into a field
+// before the confirm button enables. Reserve it for the worst-case
+// actions: archive-this-certificate, delete-root-CA, etc.
+//
+// Visual posture: destructive variant uses red surface tints + a red
+// confirm button matching .btn-danger. Non-destructive uses the
+// default brand-teal confirm button.
+
+import { Fragment, useState, useEffect, useRef } from 'react';
+import { Dialog, Transition } from '@headlessui/react';
+
+export interface ConfirmDialogProps {
+  /** Controls visibility. Parent owns the boolean. */
+  open: boolean;
+  /** Title shown at the top of the dialog. Concise: "Archive certificate". */
+  title: string;
+  /** Body copy. Plain text recommended; spell out consequences. */
+  message: string;
+  /** Label for the confirm button. Defaults to "Confirm". */
+  confirmLabel?: string;
+  /** Label for the cancel button. Defaults to "Cancel". */
+  cancelLabel?: string;
+  /** When true, confirm button uses .btn-danger styling. */
+  destructive?: boolean;
+  /**
+   * When set, the operator must type this exact string before the
+   * confirm button enables. Use for the most irreversible actions
+   * (archive certificate, delete CA, etc.).
+   */
+  typedConfirmation?: string;
+  /** Fires when the confirm button is clicked. Parent closes the dialog. */
+  onConfirm: () => void;
+  /** Fires on ESC, backdrop click, or cancel button. */
+  onCancel: () => void;
+}
+
+export default function ConfirmDialog({
+  open,
+  title,
+  message,
+  confirmLabel = 'Confirm',
+  cancelLabel = 'Cancel',
+  destructive = false,
+  typedConfirmation,
+  onConfirm,
+  onCancel,
+}: ConfirmDialogProps) {
+  const [typedValue, setTypedValue] = useState('');
+  const cancelButtonRef = useRef<HTMLButtonElement>(null);
+
+  // Reset typed-confirmation state every time the dialog closes/reopens.
+  // Without this, a previous successful confirmation leaves the field
+  // pre-filled on the next confirmation prompt — that's a footgun.
+  useEffect(() => {
+    if (open) setTypedValue('');
+  }, [open]);
+
+  const typedOK = !typedConfirmation || typedValue === typedConfirmation;
+  const confirmDisabled = !typedOK;
+
+  const confirmClass = destructive
+    ? 'btn btn-danger'
+    : 'btn btn-primary';
+
+  return (
+    <Transition show={open} as={Fragment}>
+      <Dialog
+        as="div"
+        className="relative z-50"
+        onClose={onCancel}
+        initialFocus={cancelButtonRef}
+      >
+        {/* Backdrop */}
+        <Transition.Child
+          as={Fragment}
+          enter="ease-out duration-150"
+          enterFrom="opacity-0"
+          enterTo="opacity-100"
+          leave="ease-in duration-100"
+          leaveFrom="opacity-100"
+          leaveTo="opacity-0"
+        >
+          <div className="fixed inset-0 bg-black/40" aria-hidden="true" />
+        </Transition.Child>
+
+        <div className="fixed inset-0 overflow-y-auto">
+          <div className="flex min-h-full items-center justify-center p-4">
+            <Transition.Child
+              as={Fragment}
+              enter="ease-out duration-150"
+              enterFrom="opacity-0 translate-y-2 scale-95"
+              enterTo="opacity-100 translate-y-0 scale-100"
+              leave="ease-in duration-100"
+              leaveFrom="opacity-100 translate-y-0 scale-100"
+              leaveTo="opacity-0 translate-y-2 scale-95"
+            >
+              <Dialog.Panel
+                className={`w-full max-w-md transform overflow-hidden rounded-lg bg-surface shadow-xl border ${
+                  destructive ? 'border-red-200' : 'border-surface-border'
+                } p-6`}
+              >
+                <Dialog.Title
+                  as="h3"
+                  className="text-lg font-semibold text-ink"
+                >
+                  {title}
+                </Dialog.Title>
+                <Dialog.Description
+                  as="p"
+                  className="mt-2 text-sm text-ink-muted"
+                >
+                  {message}
+                </Dialog.Description>
+
+                {typedConfirmation && (
+                  <div className="mt-4">
+                    <label
+                      htmlFor="confirm-typed-input"
+                      className="block text-xs font-medium text-ink-muted mb-1"
+                    >
+                      Type{' '}
+                      <code className="text-ink font-mono">
+                        {typedConfirmation}
+                      </code>{' '}
+                      to enable confirmation:
+                    </label>
+                    <input
+                      id="confirm-typed-input"
+                      type="text"
+                      autoComplete="off"
+                      autoFocus
+                      value={typedValue}
+                      onChange={(e) => setTypedValue(e.target.value)}
+                      className="input w-full"
+                    />
+                  </div>
+                )}
+
+                <div className="mt-6 flex justify-end gap-2">
+                  <button
+                    ref={cancelButtonRef}
+                    type="button"
+                    className="btn btn-outline"
+                    onClick={onCancel}
+                  >
+                    {cancelLabel}
+                  </button>
+                  <button
+                    type="button"
+                    className={confirmClass}
+                    onClick={onConfirm}
+                    disabled={confirmDisabled}
+                  >
+                    {confirmLabel}
+                  </button>
+                </div>
+              </Dialog.Panel>
+            </Transition.Child>
+          </div>
+        </div>
+      </Dialog>
+    </Transition>
+  );
+}
@@ -1,3 +1,6 @@
+import type { ReactNode } from 'react';
+import Skeleton from './Skeleton';
+
 interface Column<T> {
  key: string;
  label: string;
@@ -28,6 +31,14 @@ interface DataTableProps<T> {
  data: T[];
  onRowClick?: (item: T) => void;
  emptyMessage?: string;
+  /**
+   * UX-M3 / Phase 1: rich empty-state slot. Pass an <EmptyState />
+   * component (or any ReactNode) here when the page wants a CTA-driven
+   * first-run experience instead of the bare emptyMessage string. The
+   * existing `emptyMessage` prop is preserved for backward compat with
+   * the ~18 list-page call sites that pass a simple string.
+   */
+  emptyState?: ReactNode;
  isLoading?: boolean;
  keyField?: string;
  selectable?: boolean;
@@ -36,20 +47,24 @@ interface DataTableProps<T> {
  pagination?: PaginationProps;
 }

-export default function DataTable<T>({ columns, data, onRowClick, emptyMessage, isLoading, keyField = 'id', selectable, selectedKeys, onSelectionChange, pagination }: DataTableProps<T>) {
+export default function DataTable<T>({ columns, data, onRowClick, emptyMessage, emptyState, isLoading, keyField = 'id', selectable, selectedKeys, onSelectionChange, pagination }: DataTableProps<T>) {
+  // Phase 4 closure (UX-M1): swap the centered spinner + "Loading..."
+  // text — which paints into a tiny vertical span and then jumps to a
+  // full-height table on resolve, the canonical CLS source — for a
+  // layout-shape-matching skeleton table sized to the actual column
+  // count. The eye reads "table loading here" and the eventual data
+  // lands in the same DOM rectangle with zero reflow.
  if (isLoading) {
-    return (
-      <div className="flex items-center justify-center py-16 text-ink-muted">
-        <svg className="animate-spin h-5 w-5 mr-3" viewBox="0 0 24 24">
-          <circle className="opacity-25" cx="12" cy="12" r="10" stroke="currentColor" strokeWidth="4" fill="none" />
-          <path className="opacity-75" fill="currentColor" d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4z" />
-        </svg>
-        Loading...
-      </div>
-    );
+    return <Skeleton variant="table" columns={columns.length + (selectable ? 1 : 0)} />;
  }

  if (!data.length) {
+    // UX-M3 / Phase 1: prefer the rich <EmptyState /> slot when supplied;
+    // fall back to the legacy string render so existing call sites with
+    // emptyMessage="…" stay unchanged.
+    if (emptyState) {
+      return <>{emptyState}</>;
+    }
    return (
      <div className="flex items-center justify-center py-16 text-ink-faint">
        {emptyMessage || 'No data found'}
@@ -83,7 +98,7 @@ export default function DataTable<T>({ columns, data, onRowClick, emptyMessage,
        <thead>
          <tr className="border-b-2 border-surface-border bg-surface-muted">
            {selectable && (
-              <th className="px-3 py-3 w-10">
+              <th scope="col" className="px-3 py-3 w-10">
                <input
                  type="checkbox"
                  checked={allSelected || false}
@@ -93,7 +108,7 @@ export default function DataTable<T>({ columns, data, onRowClick, emptyMessage,
              </th>
            )}
            {columns.map(col => (
-              <th key={col.key} className={`px-4 py-3 text-left text-xs font-semibold text-ink-muted uppercase tracking-wider ${col.className || ''}`}>
+              <th key={col.key} scope="col" className={`px-4 py-3 text-left text-xs font-semibold text-ink-muted uppercase tracking-wider ${col.className || ''}`}>
                {col.label}
              </th>
            ))}
@@ -0,0 +1,78 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+
+import { render, screen, fireEvent } from '@testing-library/react';
+import { describe, it, expect, vi } from 'vitest';
+import EmptyState from './EmptyState';
+
+describe('EmptyState', () => {
+  it('renders the title', () => {
+    render(<EmptyState title="No certificates yet" />);
+    expect(screen.getByText('No certificates yet')).toBeInTheDocument();
+  });
+
+  it('renders description when provided', () => {
+    render(
+      <EmptyState
+        title="No certificates yet"
+        description="Issue your first certificate to get started."
+      />,
+    );
+    expect(
+      screen.getByText('Issue your first certificate to get started.'),
+    ).toBeInTheDocument();
+  });
+
+  it('renders icon slot when provided', () => {
+    render(
+      <EmptyState
+        icon={<span data-testid="empty-icon">📜</span>}
+        title="No certificates"
+      />,
+    );
+    expect(screen.getByTestId('empty-icon')).toBeInTheDocument();
+  });
+
+  it('renders primaryAction button and fires its onClick', () => {
+    const onClick = vi.fn();
+    render(
+      <EmptyState
+        title="No certificates"
+        primaryAction={{ label: 'Issue certificate', onClick }}
+      />,
+    );
+    fireEvent.click(screen.getByRole('button', { name: 'Issue certificate' }));
+    expect(onClick).toHaveBeenCalledTimes(1);
+  });
+
+  it('renders secondaryAction button and fires its onClick', () => {
+    const onClick = vi.fn();
+    render(
+      <EmptyState
+        title="No certificates"
+        secondaryAction={{ label: 'Read docs', onClick }}
+      />,
+    );
+    fireEvent.click(screen.getByRole('button', { name: 'Read docs' }));
+    expect(onClick).toHaveBeenCalledTimes(1);
+  });
+
+  it('renders both actions side-by-side', () => {
+    render(
+      <EmptyState
+        title="No certificates"
+        primaryAction={{ label: 'Issue', onClick: () => {} }}
+        secondaryAction={{ label: 'Connect issuer', onClick: () => {} }}
+      />,
+    );
+    expect(screen.getByRole('button', { name: 'Issue' })).toBeInTheDocument();
+    expect(
+      screen.getByRole('button', { name: 'Connect issuer' }),
+    ).toBeInTheDocument();
+  });
+
+  it('exposes role="status" for screen readers', () => {
+    render(<EmptyState title="No data" />);
+    expect(screen.getByRole('status')).toBeInTheDocument();
+  });
+});
@@ -0,0 +1,95 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// EmptyState — the certctl-themed empty-state primitive. Phase 1
+// closure for UX-M3 (no <EmptyState> primitive; DataTable shows a bare
+// 'No data found' string).
+//
+// Two render paths:
+//   1) `<EmptyState title="..." description="..." />` — minimum
+//      acceptable empty state. Title is required (the user must
+//      understand what's missing); description + actions are optional.
+//   2) `<EmptyState icon={<Icon />} title="..." description="..."
+//        primaryAction={{ label, onClick }} secondaryAction={...} />` —
+//      first-run CTA shape. Renders icon at the top, title in the
+//      middle, two action buttons at the bottom. Use this on list pages
+//      that an operator might hit on their first visit ("No certs yet —
+//      [Issue first certificate] [Connect an issuer]").
+//
+// Composition with DataTable: DataTable accepts `emptyState?: ReactNode`
+// (added alongside the existing `emptyMessage?: string` for backward
+// compat) so list pages can pass either a string or a full <EmptyState />
+// component.
+
+import type { ReactNode } from 'react';
+
+export interface EmptyStateAction {
+  label: string;
+  onClick: () => void;
+}
+
+export interface EmptyStateProps {
+  /** Optional icon at the top. Pass any ReactNode (lucide / SVG / emoji). */
+  icon?: ReactNode;
+  /** Required headline. Keep short: "No certificates yet". */
+  title: string;
+  /** Optional sub-copy. One sentence explaining the empty condition. */
+  description?: string;
+  /** Optional primary CTA. Renders as .btn-primary. */
+  primaryAction?: EmptyStateAction;
+  /** Optional secondary CTA. Renders as .btn-outline alongside primary. */
+  secondaryAction?: EmptyStateAction;
+  /** Override default centering / padding when nested inside a card. */
+  className?: string;
+}
+
+export default function EmptyState({
+  icon,
+  title,
+  description,
+  primaryAction,
+  secondaryAction,
+  className,
+}: EmptyStateProps) {
+  return (
+    <div
+      role="status"
+      className={
+        className ||
+        'flex flex-col items-center justify-center text-center py-16 px-6'
+      }
+    >
+      {icon && (
+        <div className="mb-4 text-ink-faint" aria-hidden="true">
+          {icon}
+        </div>
+      )}
+      <h3 className="text-base font-semibold text-ink mb-1">{title}</h3>
+      {description && (
+        <p className="text-sm text-ink-muted max-w-md mb-4">{description}</p>
+      )}
+      {(primaryAction || secondaryAction) && (
+        <div className="flex items-center gap-2 mt-2">
+          {primaryAction && (
+            <button
+              type="button"
+              className="btn btn-primary"
+              onClick={primaryAction.onClick}
+            >
+              {primaryAction.label}
+            </button>
+          )}
+          {secondaryAction && (
+            <button
+              type="button"
+              className="btn btn-outline"
+              onClick={secondaryAction.onClick}
+            >
+              {secondaryAction.label}
+            </button>
+          )}
+        </div>
+      )}
+    </div>
+  );
+}
@@ -0,0 +1,112 @@
+import { describe, it, expect } from 'vitest';
+import { render, screen, fireEvent } from '@testing-library/react';
+import { useForm } from 'react-hook-form';
+import FormField from './FormField';
+
+describe('FormField', () => {
+  it('label htmlFor matches input id (the WCAG 1.3.1 contract)', () => {
+    render(
+      <FormField label="Email">
+        <input type="email" />
+      </FormField>,
+    );
+    const label = screen.getByText('Email');
+    const input = screen.getByLabelText('Email');
+    // Programmatic label association — what screen readers use.
+    expect(input).toBeInTheDocument();
+    expect(label).toHaveAttribute('for', input.id);
+    // useId() gives a non-empty id by definition.
+    expect(input.id).toMatch(/^field-/);
+  });
+
+  it('two siblings get independent ids (no collision)', () => {
+    render(
+      <>
+        <FormField label="Name"><input /></FormField>
+        <FormField label="Description"><input /></FormField>
+      </>,
+    );
+    const a = screen.getByLabelText('Name');
+    const b = screen.getByLabelText('Description');
+    expect(a.id).not.toBe(b.id);
+  });
+
+  it('required surfaces the asterisk + aria-required on the child', () => {
+    render(
+      <FormField label="Email" required>
+        <input type="email" />
+      </FormField>,
+    );
+    expect(screen.getByText('*')).toBeInTheDocument();
+    expect(screen.getByLabelText(/Email/)).toHaveAttribute('aria-required', 'true');
+  });
+
+  it('description wires aria-describedby to the child', () => {
+    render(
+      <FormField label="Token" description="Paste the API key from /auth/keys">
+        <input />
+      </FormField>,
+    );
+    const input = screen.getByLabelText('Token');
+    const desc = screen.getByText(/Paste the API key/);
+    expect(input.getAttribute('aria-describedby')).toContain(desc.id);
+  });
+
+  it('error sets aria-invalid + role=alert + extends aria-describedby', () => {
+    render(
+      <FormField label="Email" error="Must be a valid email address">
+        <input type="email" />
+      </FormField>,
+    );
+    const input = screen.getByLabelText('Email');
+    expect(input).toHaveAttribute('aria-invalid', 'true');
+    const err = screen.getByRole('alert');
+    expect(err).toHaveTextContent('Must be a valid email address');
+    expect(input.getAttribute('aria-describedby')).toContain(err.id);
+  });
+
+  it('composes cleanly with react-hook-form register() — spread + clone preserves both', () => {
+    function Form({ onSubmit }: { onSubmit: (v: { name: string }) => void }) {
+      const { register, handleSubmit } = useForm<{ name: string }>();
+      return (
+        <form onSubmit={handleSubmit(onSubmit)}>
+          <FormField label="Name">
+            <input {...register('name')} />
+          </FormField>
+          <button type="submit">Save</button>
+        </form>
+      );
+    }
+    let captured = '';
+    render(<Form onSubmit={(v) => { captured = v.name; }} />);
+    const input = screen.getByLabelText('Name');
+    fireEvent.change(input, { target: { value: 'alice' } });
+    fireEvent.click(screen.getByText('Save'));
+    return new Promise<void>((resolve) => {
+      setTimeout(() => {
+        expect(captured).toBe('alice');
+        // Both RHF's name and FormField's id co-exist.
+        expect(input.getAttribute('name')).toBe('name');
+        expect(input.id).toMatch(/^field-/);
+        resolve();
+      }, 10);
+    });
+  });
+
+  it('throws clearly when child is not a single valid element', () => {
+    // Suppress React's error-boundary console spam for this assertion.
+    const orig = console.error;
+    console.error = () => {};
+    try {
+      expect(() =>
+        render(
+          <FormField label="Bad">
+            {'plain string is not valid'}
+          </FormField>,
+        ),
+      ).toThrow();
+    } finally {
+      console.error = orig;
+    }
+  });
+});
@@ -0,0 +1,118 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// FormField — Phase 5 closure for UX-H4 + the foundation of FE-M1.
+//
+// Pre-Phase-5 state: 139 <label> elements in production tsx; 6 with
+// htmlFor; 0 inputs with id. WCAG 1.3.1 (info-and-relationships) fails
+// on ~99% of form fields — screen readers can't programmatically pair
+// a label with its input, so "Email" reads as a floating string rather
+// than as the accessible name of the adjacent input.
+//
+// FormField fixes this by generating a stable id with React 18's
+// useId() and threading it to BOTH the <label htmlFor=...> AND the
+// child input's id prop via cloneElement. Consumers write:
+//
+//   <FormField label="Email" required>
+//     <input type="email" value={email} onChange={…} />
+//   </FormField>
+//
+// — no manual id wiring, no risk of id-mismatch drift, no chance a
+// developer copies the JSX and forgets to update one of the two
+// strings. The label-↔-input binding is correct by construction.
+//
+// Composition with react-hook-form is straight-forward — RHF's
+// register('field') returns onChange/onBlur/ref/name which spread onto
+// the input alongside FormField's auto-id. The Zod-resolver path picks
+// up errors and FormField surfaces them via the `error` prop slot.
+
+import { Children, cloneElement, isValidElement, useId } from 'react';
+import type { ReactElement, ReactNode } from 'react';
+
+interface FormFieldProps {
+  /** Visible label text. Required for a11y — never render an unbound input. */
+  label: string;
+  /** Render `*` next to the label when true (display-only; validation lives in Zod). */
+  required?: boolean;
+  /** Optional helper / description text below the input. */
+  description?: string;
+  /** Optional error message — when set, surfaces below the input + flags aria-invalid. */
+  error?: string;
+  /** Optional class override for the wrapping div. */
+  className?: string;
+  /**
+   * Exactly one input-shaped child (<input>, <select>, <textarea>, or any
+   * forwardRef'd component that accepts `id` + `aria-describedby` +
+   * `aria-invalid` as props). FormField clones it and injects the
+   * auto-generated id so the label-↔-input pairing is correct by
+   * construction.
+   */
+  children: ReactNode;
+}
+
+export default function FormField({
+  label,
+  required,
+  description,
+  error,
+  className,
+  children,
+}: FormFieldProps) {
+  // useId() returns a stable id that's unique per render-tree-position,
+  // safe under StrictMode, and SSR-friendly. Two siblings get different
+  // ids automatically.
+  const reactId = useId();
+  const inputId = `field-${reactId}`;
+  const descId = description ? `desc-${reactId}` : undefined;
+  const errorId = error ? `err-${reactId}` : undefined;
+
+  // Build the aria-describedby chain from optional description + error.
+  // Browsers concatenate space-separated ids, so screen readers announce
+  // "Email, [description], [error]".
+  const describedBy = [descId, errorId].filter(Boolean).join(' ') || undefined;
+
+  const onlyChild = Children.only(children);
+  if (!isValidElement(onlyChild)) {
+    // Surface a clear error in dev rather than render a broken control.
+    throw new Error('FormField expects exactly one valid React element child');
+  }
+
+  // cloneElement preserves the child's existing props (including any
+  // RHF `register(...)` spread) and overlays the FormField-managed
+  // a11y props on top. The child's `id` / `aria-*` are always set
+  // here, but `name`/`value`/`onChange` from the child are preserved.
+  const childWithA11y = cloneElement(
+    onlyChild as ReactElement<Record<string, unknown>>,
+    {
+      id: inputId,
+      'aria-describedby': describedBy,
+      'aria-invalid': error ? true : undefined,
+      'aria-required': required ? true : undefined,
+    },
+  );
+
+  return (
+    <div className={className ?? 'mb-4'}>
+      <label
+        htmlFor={inputId}
+        className="block text-sm font-medium text-ink mb-1.5"
+      >
+        {label}
+        {required && (
+          <span className="text-red-600 ml-0.5" aria-hidden="true">*</span>
+        )}
+      </label>
+      {childWithA11y}
+      {description && (
+        <p id={descId} className="mt-1 text-xs text-ink-muted">
+          {description}
+        </p>
+      )}
+      {error && (
+        <p id={errorId} role="alert" className="mt-1 text-xs text-red-700">
+          {error}
+        </p>
+      )}
+    </div>
+  );
+}
@@ -1,62 +1,202 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Phase 3 joint closure (UX-H1 + FE-H2 + FE-L4, 2026-05-14):
+//
+//   UX-H1 — sidebar regrouped from a flat 31-item list into 7 semantic
+//   groups: Inventory, Trust, Delivery, People, Notify, Access, Audit.
+//   Audit-accuracy callout: the original UX-H1 finding's wording
+//   ("/auth/* completely absent from primary nav") was factually wrong
+//   — all 8 /auth/* entries + /audit were already in the array; the
+//   issue was UNGROUPED, not absent. The correct framing is "31 flat
+//   items, no hierarchy, scroll-list to find Audit Trail."
+//
+//   FE-H2 — every nav item now carries a lucide-react icon component
+//   reference instead of a literal SVG path string. 31 path strings
+//   removed; 27 named lucide imports added.
+//
+//   FE-L4 — collapsible groups (click the group header to fold/unfold)
+//   give the keyboard-first power-user a way to compact the sidebar
+//   to just the surfaces they care about. State persists per-group in
+//   localStorage so the choice survives reloads.
+//
+// FE-M6 (CSP unsafe-inline tightening) is NOT closed here — pre-Phase-3
+// re-verification confirmed the CSP comment on style-src 'unsafe-inline'
+// cites "Tailwind (via Vite) injects per-component <style> blocks at
+// build time," not inline SVG attributes. There are also 17 production
+// tsx files with React style={...} attributes (Tooltip, AgentFleetPage,
+// UsersPage, etc.) that emit inline styles. Tightening the CSP needs
+// all those paths migrated to utility classes/CSS variables — out of
+// scope for this phase.
+
+import { useState, useEffect } from 'react';
 import { NavLink, Outlet, useNavigate } from 'react-router-dom';
+import {
+  // Inventory
+  LayoutDashboard, ShieldCheck, Search, Server, Network, Radar, Timer,
+  // Trust
+  KeyRound, FileText, ScrollText, RefreshCw, Wrench,
+  // Delivery
+  Target, ListTodo, HeartPulse,
+  // People
+  User, Users, Group,
+  // Notify
+  Bell, Inbox, Activity,
+  // Access
+  Clock, UserCog, CheckCircle2, AlertTriangle, Cog,
+  // Logout + setup
+  LogOut, HelpCircle,
+  // Group header chevron
+  ChevronDown, ChevronRight,
+} from 'lucide-react';
+import type { LucideIcon } from 'lucide-react';
 import { useAuth } from './AuthProvider';
+import { ExternalLink } from './ExternalLink';
 import logo from '../assets/certctl-logo.png';

-const nav = [
-  { to: '/',              label: 'Dashboard',     icon: 'M3 12l2-2m0 0l7-7 7 7M5 10v10a1 1 0 001 1h3m10-11l2 2m-2-2v10a1 1 0 01-1 1h-3m-4 0h4' },
-  { to: '/certificates',  label: 'Certificates',  icon: 'M9 12l2 2 4-4m5.618-4.016A11.955 11.955 0 0112 2.944a11.955 11.955 0 01-8.618 3.04A12.02 12.02 0 003 9c0 5.591 3.824 10.29 9 11.622 5.176-1.332 9-6.03 9-11.622 0-1.042-.133-2.052-.382-3.016z' },
-  { to: '/agents',        label: 'Agents',        icon: 'M5 12h14M5 12a2 2 0 01-2-2V6a2 2 0 012-2h14a2 2 0 012 2v4a2 2 0 01-2 2M5 12a2 2 0 00-2 2v4a2 2 0 002 2h14a2 2 0 002-2v-4a2 2 0 00-2-2' },
-  { to: '/fleet',          label: 'Fleet Overview', icon: 'M3.055 11H5a2 2 0 012 2v1a2 2 0 002 2 2 2 0 012 2v2.945M8 3.935V5.5A2.5 2.5 0 0010.5 8h.5a2 2 0 012 2 2 2 0 104 0 2 2 0 012-2h1.064M15 20.488V18a2 2 0 012-2h3.064M21 12a9 9 0 11-18 0 9 9 0 0118 0z' },
-  { to: '/jobs',          label: 'Jobs',          icon: 'M4 4v5h.582m15.356 2A8.001 8.001 0 004.582 9m0 0H9m11 11v-5h-.581m0 0a8.003 8.003 0 01-15.357-2m15.357 2H15' },
-  { to: '/notifications', label: 'Notifications', icon: 'M15 17h5l-1.405-1.405A2.032 2.032 0 0118 14.158V11a6.002 6.002 0 00-4-5.659V5a2 2 0 10-4 0v.341C7.67 6.165 6 8.388 6 11v3.159c0 .538-.214 1.055-.595 1.436L4 17h5m6 0v1a3 3 0 11-6 0v-1m6 0H9' },
-  { to: '/policies',      label: 'Policies',      icon: 'M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2m-6 9l2 2 4-4' },
-  { to: '/renewal-policies', label: 'Renewal Policies', icon: 'M4 4v5h.582m15.356 2A8.001 8.001 0 004.582 9m0 0H9m11 11v-5h-.581m0 0a8.003 8.003 0 01-15.357-2m15.357 2H15' },
-  { to: '/profiles',      label: 'Profiles',      icon: 'M10.325 4.317c.426-1.756 2.924-1.756 3.35 0a1.724 1.724 0 002.573 1.066c1.543-.94 3.31.826 2.37 2.37a1.724 1.724 0 001.066 2.573c1.756.426 1.756 2.924 0 3.35a1.724 1.724 0 00-1.066 2.573c.94 1.543-.826 3.31-2.37 2.37a1.724 1.724 0 00-2.573 1.066c-.426 1.756-2.924 1.756-3.35 0a1.724 1.724 0 00-2.573-1.066c-1.543.94-3.31-.826-2.37-2.37a1.724 1.724 0 00-1.066-2.573c-1.756-.426-1.756-2.924 0-3.35a1.724 1.724 0 001.066-2.573c-.94-1.543.826-3.31 2.37-2.37.996.608 2.296.07 2.572-1.065z M15 12a3 3 0 11-6 0 3 3 0 016 0z' },
-  { to: '/issuers',       label: 'Issuers',       icon: 'M15 7a2 2 0 012 2m4 0a6 6 0 01-7.743 5.743L11 17H9v2H7v2H4a1 1 0 01-1-1v-2.586a1 1 0 01.293-.707l5.964-5.964A6 6 0 1121 9z' },
-  { to: '/targets',       label: 'Targets',       icon: 'M19 11H5m14 0a2 2 0 012 2v6a2 2 0 01-2 2H5a2 2 0 01-2-2v-6a2 2 0 012-2m14 0V9a2 2 0 00-2-2M5 11V9a2 2 0 012-2m0 0V5a2 2 0 012-2h6a2 2 0 012 2v2M7 7h10' },
-  { to: '/owners',        label: 'Owners',        icon: 'M16 7a4 4 0 11-8 0 4 4 0 018 0zM12 14a7 7 0 00-7 7h14a7 7 0 00-7-7z' },
-  { to: '/teams',         label: 'Teams',         icon: 'M17 20h5v-2a3 3 0 00-5.356-1.857M17 20H7m10 0v-2c0-.656-.126-1.283-.356-1.857M7 20H2v-2a3 3 0 015.356-1.857M7 20v-2c0-.656.126-1.283.356-1.857m0 0a5.002 5.002 0 019.288 0M15 7a3 3 0 11-6 0 3 3 0 016 0zm6 3a2 2 0 11-4 0 2 2 0 014 0zM7 10a2 2 0 11-4 0 2 2 0 014 0z' },
-  { to: '/agent-groups',  label: 'Agent Groups',  icon: 'M19 11H5m14 0a2 2 0 012 2v6a2 2 0 01-2 2H5a2 2 0 01-2-2v-6a2 2 0 012-2m14 0V9a2 2 0 00-2-2M5 11V9a2 2 0 012-2m0 0V5a2 2 0 012-2h6a2 2 0 012 2v2M7 7h10 M9 3v2m6-2v2' },
-  { to: '/discovery',     label: 'Discovery',       icon: 'M21 21l-6-6m2-5a7 7 0 11-14 0 7 7 0 0114 0z' },
-  { to: '/network-scans', label: 'Network Scans',  icon: 'M3.055 11H5a2 2 0 012 2v1a2 2 0 002 2 2 2 0 012 2v2.945M8 3.935V5.5A2.5 2.5 0 0010.5 8h.5a2 2 0 012 2 2 2 0 104 0 2 2 0 012-2h1.064M15 20.488V18a2 2 0 012-2h3.064M21 12a9 9 0 11-18 0 9 9 0 0118 0z M9 12l2 2 4-4' },
-  { to: '/health-monitor', label: 'Health Monitor', icon: 'M4.318 6.318a4.5 4.5 0 000 6.364L12 20.364l7.682-7.682a4.5 4.5 0 00-6.364-6.364L12 7.636l-1.318-1.318a4.5 4.5 0 00-6.364 0z' },
-  { to: '/short-lived',   label: 'Short-Lived',    icon: 'M13 10V3L4 14h7v7l9-11h-7z' },
-  { to: '/digest',        label: 'Digest',         icon: 'M3 8l7.89 5.26a2 2 0 002.22 0L21 8M5 19h14a2 2 0 002-2V7a2 2 0 00-2-2H5a2 2 0 00-2 2v10a2 2 0 002 2z' },
-  { to: '/observability', label: 'Observability',  icon: 'M9 19v-6a2 2 0 00-2-2H5a2 2 0 00-2 2v6a2 2 0 002 2h2a2 2 0 002-2zm0 0V9a2 2 0 012-2h2a2 2 0 012 2v10m-6 0a2 2 0 002 2h2a2 2 0 002-2m0 0V5a2 2 0 012-2h2a2 2 0 012 2v14a2 2 0 01-2 2h-2a2 2 0 01-2-2z' },
-  { to: '/scep',          label: 'SCEP Admin',     icon: 'M12 15v2m-6 4h12a2 2 0 002-2v-6a2 2 0 00-2-2H6a2 2 0 00-2 2v6a2 2 0 002 2zm10-10V7a4 4 0 00-8 0v4h8z' },
-  { to: '/est',           label: 'EST Admin',      icon: 'M9 12l2 2 4-4m5.618-4.016A11.955 11.955 0 0112 2.944a11.955 11.955 0 01-8.618 3.04A12.02 12.02 0 003 9c0 5.591 3.824 10.29 9 11.622 5.176-1.332 9-6.03 9-11.622 0-1.042-.133-2.052-.382-3.016z' },
-  { to: '/audit',         label: 'Audit Trail',   icon: 'M12 8v4l3 3m6-3a9 9 0 11-18 0 9 9 0 0118 0z' },
-  // Bundle 1 Phase 10 — RBAC management (Roles / Keys / Settings).
-  // Bundle 2 Phase 8 — OIDC + Sessions.
-  { to: '/auth/oidc/providers', label: 'OIDC Providers', icon: 'M12 11c0 3.517-1.009 6.799-2.753 9.571m-3.44-2.04l.054-.09A13.916 13.916 0 008 11a4 4 0 118 0c0 1.017-.07 2.019-.203 3m-2.118 6.844A21.88 21.88 0 0015.171 17m3.839 1.132c.645-2.266.99-4.659.99-7.132A8 8 0 008 4.07M3 15.364c.64-1.319 1-2.8 1-4.364 0-1.457.39-2.823 1.07-4' },
-  { to: '/auth/sessions',       label: 'Sessions',       icon: 'M12 8v4l3 3m6-3a9 9 0 11-18 0 9 9 0 0118 0z' },
-  // Audit 2026-05-11 Fix 11 — UsersPage sidebar entry (MED-11 discoverability).
-  // The MED-11 closure wired UsersPage but no nav entry; operators had to know
-  // the URL /auth/users to reach the federated-user-management surface. This
-  // entry sits adjacent to Sessions because the two share the same mental
-  // model (federated identity admin). UsersPage handles its own 403 state for
-  // callers without auth.user.read so we don't need to gate the nav entry;
-  // every other entry in this array uses the same unconditional pattern.
-  { to: '/auth/users',     label: 'Users',         icon: 'M17 20h5v-2a3 3 0 00-5.356-1.857M17 20H7m10 0v-2c0-.656-.126-1.283-.356-1.857M7 20H2v-2a3 3 0 015.356-1.857M7 20v-2c0-.656.126-1.283.356-1.857m0 0a5.002 5.002 0 019.288 0M15 7a3 3 0 11-6 0 3 3 0 016 0zm6 3a2 2 0 11-4 0 2 2 0 014 0zM7 10a2 2 0 11-4 0 2 2 0 014 0z', testID: 'nav-auth-users' },
-  { to: '/auth/roles',    label: 'Roles',         icon: 'M16 7a4 4 0 11-8 0 4 4 0 018 0zM12 14a7 7 0 00-7 7h14a7 7 0 00-7-7z' },
-  { to: '/auth/keys',      label: 'API Keys',      icon: 'M15 7a2 2 0 012 2m4 0a6 6 0 01-7.743 5.743L11 17H9v2H7v2H4a1 1 0 01-1-1v-2.586a1 1 0 01.293-.707l5.964-5.964A6 6 0 1121 9z' },
-  { to: '/auth/approvals', label: 'Approvals',     icon: 'M9 12l2 2 4-4m6 2a9 9 0 11-18 0 9 9 0 0118 0z' },
-  // Audit 2026-05-10 CRIT-4 closure — break-glass admin surface.
-  { to: '/auth/breakglass', label: 'Break-glass',  icon: 'M12 9v2m0 4h.01m-6.938 4h13.856c1.54 0 2.502-1.667 1.732-3L13.732 4c-.77-1.333-2.694-1.333-3.464 0L3.34 16c-.77 1.333.192 3 1.732 3z' },
-  { to: '/auth/settings',  label: 'Auth Settings', icon: 'M10.325 4.317c.426-1.756 2.924-1.756 3.35 0a1.724 1.724 0 002.573 1.066c1.543-.94 3.31.826 2.37 2.37a1.724 1.724 0 001.066 2.573c1.756.426 1.756 2.924 0 3.35a1.724 1.724 0 00-1.066 2.573c.94 1.543-.826 3.31-2.37 2.37a1.724 1.724 0 00-2.573 1.066c-.426 1.756-2.924 1.756-3.35 0a1.724 1.724 0 00-2.573-1.066c-1.543.94-3.31-.826-2.37-2.37a1.724 1.724 0 00-1.066-2.573c-1.756-.426-1.756-2.924 0-3.35a1.724 1.724 0 001.066-2.573c-.94-1.543.826-3.31 2.37-2.37.996.608 2.296.07 2.572-1.065z M15 12a3 3 0 11-6 0 3 3 0 016 0z' },
-];
-
-function Icon({ d }: { d: string }) {
-  return (
-    <svg className="w-[18px] h-[18px] shrink-0" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={1.5}>
-      <path strokeLinecap="round" strokeLinejoin="round" d={d} />
-    </svg>
-  );
+// -----------------------------------------------------------------------------
+// Nav model — 7 semantic groups across 31 items.
+// -----------------------------------------------------------------------------
+interface NavItem {
+  to: string;
+  label: string;
+  icon: LucideIcon;
+  /** Optional data-testid; today only `nav-auth-users` (Audit 2026-05-11 Fix 11). */
+  testID?: string;
+}
+interface NavGroup {
+  /** localStorage key suffix for collapsed-state persistence. */
+  id: string;
+  /** Sidebar header label. */
+  label: string;
+  items: NavItem[];
 }

+const navGroups: NavGroup[] = [
+  {
+    id: 'inventory',
+    label: 'Inventory',
+    items: [
+      { to: '/',               label: 'Dashboard',      icon: LayoutDashboard },
+      { to: '/certificates',   label: 'Certificates',   icon: ShieldCheck },
+      { to: '/discovery',      label: 'Discovery',      icon: Search },
+      { to: '/agents',         label: 'Agents',         icon: Server },
+      { to: '/fleet',          label: 'Fleet Overview', icon: Network },
+      { to: '/network-scans',  label: 'Network Scans',  icon: Radar },
+      { to: '/short-lived',    label: 'Short-Lived',    icon: Timer },
+    ],
+  },
+  {
+    id: 'trust',
+    label: 'Trust',
+    items: [
+      { to: '/issuers',          label: 'Issuers',          icon: KeyRound },
+      { to: '/profiles',         label: 'Profiles',         icon: FileText },
+      { to: '/policies',         label: 'Policies',         icon: ScrollText },
+      { to: '/renewal-policies', label: 'Renewal Policies', icon: RefreshCw },
+      { to: '/scep',             label: 'SCEP Admin',       icon: Wrench },
+      { to: '/est',              label: 'EST Admin',        icon: Wrench },
+    ],
+  },
+  {
+    id: 'delivery',
+    label: 'Delivery',
+    items: [
+      { to: '/targets',         label: 'Targets',        icon: Target },
+      { to: '/jobs',            label: 'Jobs',           icon: ListTodo },
+      { to: '/health-monitor',  label: 'Health Monitor', icon: HeartPulse },
+    ],
+  },
+  {
+    id: 'people',
+    label: 'People',
+    items: [
+      { to: '/owners',       label: 'Owners',       icon: User },
+      { to: '/teams',        label: 'Teams',        icon: Users },
+      { to: '/agent-groups', label: 'Agent Groups', icon: Group },
+    ],
+  },
+  {
+    id: 'notify',
+    label: 'Notify',
+    items: [
+      { to: '/notifications', label: 'Notifications', icon: Bell },
+      { to: '/digest',        label: 'Digest',        icon: Inbox },
+      { to: '/observability', label: 'Observability', icon: Activity },
+    ],
+  },
+  {
+    id: 'access',
+    label: 'Access',
+    items: [
+      // Bundle 2 Phase 8 — OIDC + Sessions.
+      { to: '/auth/oidc/providers', label: 'OIDC Providers', icon: ShieldCheck },
+      { to: '/auth/sessions',       label: 'Sessions',       icon: Clock },
+      // Audit 2026-05-11 Fix 11 — `nav-auth-users` testid pins this entry's
+      // selectability; sit Users immediately after Sessions to preserve the
+      // federated-identity DOM order asserted in Layout.test.tsx.
+      { to: '/auth/users',          label: 'Users',          icon: Users,    testID: 'nav-auth-users' },
+      { to: '/auth/roles',          label: 'Roles',          icon: UserCog },
+      { to: '/auth/keys',           label: 'API Keys',       icon: KeyRound },
+      { to: '/auth/approvals',      label: 'Approvals',      icon: CheckCircle2 },
+      // Audit 2026-05-10 CRIT-4 closure — break-glass admin.
+      { to: '/auth/breakglass',     label: 'Break-glass',    icon: AlertTriangle },
+      { to: '/auth/settings',       label: 'Auth Settings',  icon: Cog },
+    ],
+  },
+  {
+    id: 'audit',
+    label: 'Audit',
+    items: [
+      { to: '/audit', label: 'Audit Trail', icon: ScrollText },
+    ],
+  },
+];
+
+// -----------------------------------------------------------------------------
+// useCollapsedGroups — persist per-group collapsed state in localStorage.
+// -----------------------------------------------------------------------------
+const STORAGE_KEY = 'certctl:nav:collapsed-groups';
+
+function useCollapsedGroups(): [Set<string>, (id: string) => void] {
+  const [collapsed, setCollapsed] = useState<Set<string>>(() => {
+    if (typeof window === 'undefined') return new Set();
+    try {
+      const raw = localStorage.getItem(STORAGE_KEY);
+      return new Set(raw ? (JSON.parse(raw) as string[]) : []);
+    } catch {
+      return new Set();
+    }
+  });
+
+  useEffect(() => {
+    if (typeof window === 'undefined') return;
+    try {
+      localStorage.setItem(STORAGE_KEY, JSON.stringify([...collapsed]));
+    } catch {
+      /* noop — storage quota / privacy mode */
+    }
+  }, [collapsed]);
+
+  const toggle = (id: string) => {
+    setCollapsed((prev) => {
+      const next = new Set(prev);
+      if (next.has(id)) next.delete(id);
+      else next.add(id);
+      return next;
+    });
+  };
+
+  return [collapsed, toggle];
+}
+
+// -----------------------------------------------------------------------------
+// Layout
+// -----------------------------------------------------------------------------
 export default function Layout() {
  const { authRequired, logout } = useAuth();
  const navigate = useNavigate();
+  const [collapsed, toggleGroup] = useCollapsedGroups();

  const openSetupGuide = () => {
    try { localStorage.removeItem('certctl:onboarding-dismissed'); } catch { /* noop */ }
@@ -70,33 +210,66 @@ export default function Layout() {
        {/* Logo — large and prominent */}
        <div className="px-4 pt-5 pb-4 flex flex-col items-center gap-2">
          <div className="bg-white rounded-xl p-2 shadow-lg">
-            <img src={logo} alt="certctl" className="h-16 w-16" />
+            <img src={logo} alt="certctl" className="h-16 w-16" width={64} height={64} loading="eager" decoding="async" />
          </div>
          <div className="text-center">
            <h1 className="text-lg font-bold text-white tracking-tight">certctl</h1>
-            <p className="text-[10px] text-brand-300 uppercase tracking-[0.2em]">Control Plane</p>
+            <p className="text-2xs text-brand-300 uppercase tracking-[0.2em]">Control Plane</p>
          </div>
        </div>

-        <nav className="flex-1 py-2 px-3 space-y-0.5 overflow-y-auto">
-          {nav.map(item => (
-            <NavLink
-              key={item.to}
-              to={item.to}
-              end={item.to === '/'}
-              data-testid={'testID' in item ? item.testID : undefined}
-              className={({ isActive }) =>
-                `flex items-center gap-3 px-3 py-2 text-[13px] rounded transition-all duration-150 ${
-                  isActive
-                    ? 'bg-white/15 text-white font-semibold shadow-sm'
-                    : 'text-sidebar-text hover:text-white hover:bg-white/10'
-                }`
-              }
-            >
-              <Icon d={item.icon} />
-              {item.label}
-            </NavLink>
-          ))}
+        <nav className="flex-1 py-2 px-3 space-y-3 overflow-y-auto" aria-label="Primary navigation">
+          {navGroups.map((group) => {
+            const isCollapsed = collapsed.has(group.id);
+            return (
+              <div key={group.id} className="space-y-0.5">
+                {/* Group header — clickable to toggle collapse. */}
+                <button
+                  type="button"
+                  onClick={() => toggleGroup(group.id)}
+                  aria-expanded={!isCollapsed}
+                  aria-controls={`nav-group-${group.id}`}
+                  className="w-full flex items-center justify-between px-3 py-1.5 text-2xs uppercase tracking-wider text-brand-300/60 hover:text-brand-300 transition-colors border-t border-white/10 pt-2 mt-1 first:border-t-0 first:pt-1 first:mt-0"
+                >
+                  <span>{group.label}</span>
+                  {isCollapsed
+                    ? <ChevronRight className="w-3 h-3 shrink-0" aria-hidden="true" />
+                    : <ChevronDown  className="w-3 h-3 shrink-0" aria-hidden="true" />}
+                </button>
+                {/* Group items — fold via inline display:none when collapsed
+                    (vs unmount) so the NavLinks retain focus state and the
+                    operator's next click doesn't re-render the entire group.
+                    aria-hidden mirrors the visual state for screen readers. */}
+                <div
+                  id={`nav-group-${group.id}`}
+                  className={`space-y-0.5 ${isCollapsed ? 'hidden' : ''}`}
+                  aria-hidden={isCollapsed}
+                >
+                  {group.items.map((item) => {
+                    const ItemIcon = item.icon;
+                    return (
+                      <NavLink
+                        key={item.to}
+                        to={item.to}
+                        end={item.to === '/'}
+                        data-testid={item.testID}
+                        className={({ isActive }) =>
+                          `flex items-center gap-3 px-3 py-2 text-sm rounded transition-all duration-150 ${
+                            isActive
+                              ? 'bg-white/15 text-white font-semibold shadow-sm'
+                              : 'text-sidebar-text hover:text-white hover:bg-white/10'
+                          }`
+                        }
+                      >
+                        <ItemIcon className="w-[18px] h-[18px] shrink-0" strokeWidth={1.75} aria-hidden="true" />
+                        {item.label}
+                      </NavLink>
+                    );
+                  })}
+                </div>
+              </div>
+            );
+          })}
        </nav>

        <div className="px-3 pb-2 pt-2 border-t border-white/10">
@@ -104,24 +277,49 @@ export default function Layout() {
            type="button"
            onClick={openSetupGuide}
            title="Reopen the onboarding wizard"
-            className="w-full flex items-center gap-3 px-3 py-2 text-[13px] rounded text-sidebar-text hover:text-white hover:bg-white/10 transition-all duration-150"
+            className="w-full flex items-center gap-3 px-3 py-2 text-sm rounded text-sidebar-text hover:text-white hover:bg-white/10 transition-all duration-150"
          >
-            <Icon d="M9.663 17h4.673M12 3v1m6.364 1.636l-.707.707M21 12h-1M4 12H3m3.343-5.657l-.707-.707m2.828 9.9a5 5 0 117.072 0l-.548.547A3.374 3.374 0 0014 18.469V19a2 2 0 11-4 0v-.531c0-.895-.356-1.754-.988-2.386l-.548-.547z" />
+            <HelpCircle className="w-[18px] h-[18px] shrink-0" strokeWidth={1.75} aria-hidden="true" />
            Setup guide
          </button>
        </div>

-        <div className="px-5 py-3 border-t border-white/10 flex items-center justify-between">
-          <span className="text-[10px] text-brand-300/60 font-mono">certctl</span>
+        {/* Maintainer attribution row — mirrors the landing-page footer
+            (certctl.io: "Built and maintained by Shankar · certctl.io").
+            Same font-mono / muted-text typography; only "Shankar" carries
+            the LinkedIn link (the same href + rel="me noopener" pattern
+            the landing page uses). Single-maintainer OSS standard
+            (Cal.com, Plausible, Beekeeper Studio do the same). */}
+        {/* Maintainer attribution row. The Bundle-8 L-015 CI guard line-greps
+            for `target="_blank"` without `rel="noopener noreferrer"` on the
+            SAME LINE — splitting target + rel across lines (as the prior
+            bare <a> did) tripped the guard. ExternalLink is the canonical
+            chokepoint that the guard allowlists. We lose the rel="me" hint
+            (LinkedIn's identity-claim signal, not load-bearing), but gain
+            the CI gate. */}
+        <div className="px-5 pt-3 pb-1 border-t border-white/10">
+          <span className="text-2xs text-sidebar-text/70 font-mono">
+            Built and maintained by{' '}
+            <ExternalLink
+              href="https://www.linkedin.com/in/shankar-k-a1b6853ba"
+              className="text-sidebar-text/90 hover:text-white transition-colors underline-offset-2 hover:underline"
+              title="Shankar on LinkedIn — opens in a new tab"
+            >
+              Shankar
+            </ExternalLink>
+          </span>
+        </div>
+
+        <div className="px-5 pt-1 pb-3 flex items-center justify-between">
+          <span className="text-2xs text-brand-300/60 font-mono">certctl</span>
          {authRequired && (
            <button
              onClick={logout}
              className="text-xs text-sidebar-text hover:text-white transition-colors"
              title="Sign out"
+              aria-label="Sign out"
            >
-              <svg className="w-4 h-4" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={1.5}>
-                <path strokeLinecap="round" strokeLinejoin="round" d="M15.75 9V5.25A2.25 2.25 0 0013.5 3h-6a2.25 2.25 0 00-2.25 2.25v13.5A2.25 2.25 0 007.5 21h6a2.25 2.25 0 002.25-2.25V15m3 0l3-3m0 0l-3-3m3 3H9" />
-              </svg>
+              <LogOut className="w-4 h-4" strokeWidth={1.75} aria-hidden="true" />
            </button>
          )}
        </div>
@@ -0,0 +1,73 @@
+import { describe, it, expect, vi } from 'vitest';
+import { render, screen, fireEvent } from '@testing-library/react';
+import ModalDialog from './ModalDialog';
+
+describe('ModalDialog', () => {
+  it('renders nothing when open=false', () => {
+    render(
+      <ModalDialog open={false} title="Hidden" onClose={() => {}}>
+        body content
+      </ModalDialog>,
+    );
+    expect(screen.queryByText('Hidden')).toBeNull();
+    expect(screen.queryByText('body content')).toBeNull();
+  });
+
+  it('renders title + children when open', () => {
+    render(
+      <ModalDialog open={true} title="Confirm thing" onClose={() => {}}>
+        <p>This is the body</p>
+      </ModalDialog>,
+    );
+    expect(screen.getByText('Confirm thing')).toBeInTheDocument();
+    expect(screen.getByText('This is the body')).toBeInTheDocument();
+  });
+
+  it('Headless UI sets role=dialog + aria-modal on the panel', () => {
+    render(
+      <ModalDialog open={true} title="t" onClose={() => {}}>
+        <span>body</span>
+      </ModalDialog>,
+    );
+    const dialog = screen.getByRole('dialog');
+    expect(dialog).toHaveAttribute('aria-modal', 'true');
+  });
+
+  it('title acts as aria-labelledby target', () => {
+    render(
+      <ModalDialog open={true} title="Pin me" onClose={() => {}}>
+        <span>body</span>
+      </ModalDialog>,
+    );
+    const dialog = screen.getByRole('dialog');
+    const labelId = dialog.getAttribute('aria-labelledby');
+    expect(labelId).toBeTruthy();
+    const labelEl = document.getElementById(labelId!);
+    expect(labelEl).toHaveTextContent('Pin me');
+  });
+
+  it('ESC key fires onClose', () => {
+    const onClose = vi.fn();
+    render(
+      <ModalDialog open={true} title="x" onClose={onClose}>
+        <span>body</span>
+      </ModalDialog>,
+    );
+    fireEvent.keyDown(document, { key: 'Escape' });
+    expect(onClose).toHaveBeenCalled();
+  });
+
+  it('footer renders separately when provided', () => {
+    render(
+      <ModalDialog
+        open={true}
+        title="x"
+        onClose={() => {}}
+        footer={<button>OK</button>}
+      >
+        body
+      </ModalDialog>,
+    );
+    expect(screen.getByRole('button', { name: 'OK' })).toBeInTheDocument();
+  });
+});
@@ -0,0 +1,119 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// ModalDialog — Phase 5 closure for FE-H3 (3 inline-managed modal
+// pages — SCEPAdminPage, AgentsPage, ESTAdminPage — set
+// role="dialog" + aria-modal="true" + aria-labelledby but no focus
+// trap, no ESC-to-close, no backdrop-click-to-close).
+//
+// Built on Headless UI's <Dialog>, identical pattern to ConfirmDialog
+// (Phase 1) but accepts arbitrary <ModalDialog.Body> content rather
+// than the constrained confirm/cancel button pair ConfirmDialog
+// provides. Use ConfirmDialog for "click YES to do destructive thing";
+// use ModalDialog for "modal that contains a form / multi-action
+// content / a status display".
+//
+// What Headless UI gives us for free (same as ConfirmDialog):
+//   • automatic focus trap (Tab/Shift-Tab stays inside the dialog)
+//   • automatic ESC-to-close → onClose() callback
+//   • automatic backdrop-click-to-close → onClose() callback
+//   • role="dialog" + aria-modal="true" on the panel
+//   • aria-labelledby on the title node
+//   • <Transition> respects prefers-reduced-motion via the global
+//     @media block in src/index.css
+//
+// FE-H3 closure scope: the 3 inline-managed modal sites all get
+// migrated to this primitive in the same commit. ConfirmDialog stays
+// as-is for confirm-only flows it already serves.
+
+import { Fragment } from 'react';
+import type { ReactNode } from 'react';
+import { Dialog, Transition } from '@headlessui/react';
+
+export interface ModalDialogProps {
+  /** Controls visibility. Parent owns the boolean. */
+  open: boolean;
+  /** Title shown at the top — also acts as aria-labelledby target. */
+  title: string;
+  /** Fires on ESC, backdrop click, or external close trigger. */
+  onClose: () => void;
+  /**
+   * Dialog body — render the form, status, or multi-action content here.
+   * The body is wrapped in the styled panel; consumers don't need to
+   * wrap their content in another <div>.
+   */
+  children: ReactNode;
+  /**
+   * Footer slot for action buttons. Optional — some modals (e.g. error
+   * displays) only show a "Close" affordance which can live inside
+   * children. When provided, footer is separated by a top border.
+   */
+  footer?: ReactNode;
+  /** Maximum width — defaults to `max-w-md` (matches ConfirmDialog). */
+  maxWidth?: 'sm' | 'md' | 'lg' | 'xl' | '2xl';
+}
+
+const maxWidthMap = {
+  sm:  'max-w-sm',
+  md:  'max-w-md',
+  lg:  'max-w-lg',
+  xl:  'max-w-xl',
+  '2xl': 'max-w-2xl',
+} as const;
+
+export default function ModalDialog({
+  open,
+  title,
+  onClose,
+  children,
+  footer,
+  maxWidth = 'md',
+}: ModalDialogProps) {
+  return (
+    <Transition show={open} as={Fragment}>
+      <Dialog onClose={onClose} className="relative z-50">
+        {/* Backdrop. Headless UI wires backdrop-click → onClose. */}
+        <Transition.Child
+          as={Fragment}
+          enter="ease-out duration-200"
+          enterFrom="opacity-0"
+          enterTo="opacity-100"
+          leave="ease-in duration-150"
+          leaveFrom="opacity-100"
+          leaveTo="opacity-0"
+        >
+          <div className="fixed inset-0 bg-black/40" aria-hidden="true" />
+        </Transition.Child>
+
+        {/* Panel container. */}
+        <div className="fixed inset-0 flex items-center justify-center p-4">
+          <Transition.Child
+            as={Fragment}
+            enter="ease-out duration-200"
+            enterFrom="opacity-0 scale-95"
+            enterTo="opacity-100 scale-100"
+            leave="ease-in duration-150"
+            leaveFrom="opacity-100 scale-100"
+            leaveTo="opacity-0 scale-95"
+          >
+            <Dialog.Panel
+              className={`bg-surface w-full ${maxWidthMap[maxWidth]} rounded-lg shadow-xl border border-surface-border`}
+            >
+              <div className="p-6">
+                <Dialog.Title className="text-base font-semibold text-ink mb-3">
+                  {title}
+                </Dialog.Title>
+                <div className="text-sm text-ink">{children}</div>
+              </div>
+              {footer && (
+                <div className="border-t border-surface-border px-6 py-4 flex justify-end gap-2">
+                  {footer}
+                </div>
+              )}
+            </Dialog.Panel>
+          </Transition.Child>
+        </div>
+      </Dialog>
+    </Transition>
+  );
+}
@@ -1,3 +1,5 @@
+import Breadcrumbs from './Breadcrumbs';
+
 interface PageHeaderProps {
  title: string;
  subtitle?: string;
@@ -8,6 +10,14 @@ export default function PageHeader({ title, subtitle, action }: PageHeaderProps)
  return (
    <div className="flex items-center justify-between px-6 py-4 border-b border-surface-border bg-surface">
      <div>
+        {/* Phase 3 UX-M5 closure: breadcrumb trail derived from
+            useLocation() + the static pathSegmentLabels map in
+            Breadcrumbs.tsx (see that file's header comment for why
+            we pivoted away from the useMatches() + handle.crumb
+            pattern the audit prompt suggested). Renders nothing on
+            the dashboard root — backward-compatible with every
+            existing PageHeader consumer. */}
+        <Breadcrumbs />
        <h2 className="text-lg font-semibold text-ink">{title}</h2>
        {subtitle && <p className="text-sm text-ink-muted mt-0.5">{subtitle}</p>}
      </div>
@@ -0,0 +1,49 @@
+import { describe, it, expect } from 'vitest';
+import { render } from '@testing-library/react';
+import Skeleton from './Skeleton';
+
+describe('Skeleton', () => {
+  it('page variant renders PageHeader-shaped band + 4 stat tiles + card', () => {
+    const { container, getByRole } = render(<Skeleton variant="page" />);
+    expect(getByRole('status')).toHaveAttribute('aria-busy', 'true');
+    expect(getByRole('status')).toHaveAttribute('aria-label', 'Loading content');
+    expect(container.querySelector('.animate-pulse')).not.toBeNull();
+    // 4 stat tiles
+    expect(container.querySelectorAll('.grid > .bg-surface')).toHaveLength(4);
+  });
+
+  it('table variant defaults to 6 rows × 5 cols', () => {
+    const { container } = render(<Skeleton variant="table" />);
+    const rows = container.querySelectorAll('tbody tr');
+    expect(rows).toHaveLength(6);
+    const cells = rows[0].querySelectorAll('td');
+    expect(cells).toHaveLength(5);
+  });
+
+  it('table variant respects custom rows + columns', () => {
+    const { container } = render(<Skeleton variant="table" rows={3} columns={4} />);
+    expect(container.querySelectorAll('tbody tr')).toHaveLength(3);
+    expect(container.querySelectorAll('tbody tr:first-child td')).toHaveLength(4);
+  });
+
+  it('card variant renders title-row + 3 prose rows', () => {
+    const { container } = render(<Skeleton variant="card" />);
+    // 1 title + 3 prose lines = 4 stripes inside the inner card
+    const stripes = container.querySelectorAll('.bg-surface > div, .bg-surface .space-y-2 > div');
+    expect(stripes.length).toBeGreaterThanOrEqual(4);
+  });
+
+  it('stat variant renders label-row + number-row', () => {
+    const { container, getByRole } = render(<Skeleton variant="stat" />);
+    expect(getByRole('status')).toHaveAttribute('aria-busy', 'true');
+    // 2 stripes
+    expect(container.querySelectorAll('.bg-surface-border')).toHaveLength(2);
+  });
+
+  it('custom ariaLabel surfaces on the role=status root', () => {
+    const { getByRole } = render(
+      <Skeleton variant="card" ariaLabel="Loading certificates" />,
+    );
+    expect(getByRole('status')).toHaveAttribute('aria-label', 'Loading certificates');
+  });
+});
@@ -0,0 +1,158 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Skeleton — Phase 4 closure for UX-M1 (206 isLoading sites render as
+// "Loading…" text in PageHeader subtitle → layout shift on every fetch).
+//
+// Four variants, each shaped to match the page region it stands in for
+// so the eventual content lands without CLS:
+//
+//   • page   — full-page Suspense fallback used by main.tsx route
+//              lazy-load boundaries. Includes a PageHeader-shaped
+//              skeleton + a body grid of card / table skeletons.
+//   • table  — list-page body. 6 rows × 5 cells, header row dimmed.
+//              Drop into DataTable's isLoading branch (or page-local
+//              tables that don't go through DataTable yet).
+//   • card   — single content card. One title-row + 3 prose rows.
+//              Composable inside dashboards / detail pages.
+//   • stat   — KPI tile. One label-row + one large number-row.
+//              Sized to match DashboardPage's stat panels.
+//
+// Every variant uses Tailwind's `animate-pulse` on layout-shaped divs
+// so the eye reads "content loading here" instead of a flash of empty
+// container followed by re-flow when the real content paints.
+//
+// Accessibility: each variant carries role="status" + aria-busy="true"
+// + aria-label so screen-reader users hear "Loading <region>" instead
+// of an empty announcement.
+
+interface SkeletonProps {
+  variant: 'page' | 'table' | 'card' | 'stat';
+  /** Override default aria-label. Default: "Loading content". */
+  ariaLabel?: string;
+  /** Number of rows for the `table` variant. Default 6. */
+  rows?: number;
+  /** Number of columns for the `table` variant. Default 5. */
+  columns?: number;
+}
+
+export default function Skeleton({
+  variant,
+  ariaLabel = 'Loading content',
+  rows = 6,
+  columns = 5,
+}: SkeletonProps) {
+  if (variant === 'page') {
+    return (
+      <div
+        role="status"
+        aria-busy="true"
+        aria-label={ariaLabel}
+        className="animate-pulse"
+      >
+        {/* PageHeader-shaped band */}
+        <div className="flex items-center justify-between px-6 py-4 border-b border-surface-border bg-surface">
+          <div>
+            <div className="h-3 w-32 bg-surface-border rounded mb-2" />
+            <div className="h-5 w-48 bg-surface-border rounded" />
+          </div>
+          <div className="h-9 w-28 bg-surface-border rounded" />
+        </div>
+        {/* Body grid: 4 stat tiles + 1 card */}
+        <div className="p-6 space-y-6">
+          <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-4">
+            {Array.from({ length: 4 }).map((_, i) => (
+              <div
+                key={i}
+                className="bg-surface border border-surface-border rounded-lg p-4"
+              >
+                <div className="h-3 w-20 bg-surface-border rounded mb-3" />
+                <div className="h-7 w-16 bg-surface-border rounded" />
+              </div>
+            ))}
+          </div>
+          <Card />
+        </div>
+      </div>
+    );
+  }
+
+  if (variant === 'table') {
+    return (
+      <div
+        role="status"
+        aria-busy="true"
+        aria-label={ariaLabel}
+        className="animate-pulse"
+      >
+        <table className="w-full">
+          <thead>
+            <tr className="border-b border-surface-border">
+              {Array.from({ length: columns }).map((_, i) => (
+                <th key={i} className="text-left px-4 py-3">
+                  <div className="h-3 w-20 bg-surface-border rounded" />
+                </th>
+              ))}
+            </tr>
+          </thead>
+          <tbody>
+            {Array.from({ length: rows }).map((_, r) => (
+              <tr key={r} className="border-b border-surface-border">
+                {Array.from({ length: columns }).map((_, c) => (
+                  <td key={c} className="px-4 py-3">
+                    <div
+                      className={
+                        'h-3 bg-surface-border rounded ' +
+                        (c === 0 ? 'w-40' : c === columns - 1 ? 'w-16' : 'w-24')
+                      }
+                    />
+                  </td>
+                ))}
+              </tr>
+            ))}
+          </tbody>
+        </table>
+      </div>
+    );
+  }
+
+  if (variant === 'card') {
+    return (
+      <div
+        role="status"
+        aria-busy="true"
+        aria-label={ariaLabel}
+        className="animate-pulse"
+      >
+        <Card />
+      </div>
+    );
+  }
+
+  // variant === 'stat'
+  return (
+    <div
+      role="status"
+      aria-busy="true"
+      aria-label={ariaLabel}
+      className="animate-pulse bg-surface border border-surface-border rounded-lg p-4"
+    >
+      <div className="h-3 w-20 bg-surface-border rounded mb-3" />
+      <div className="h-7 w-16 bg-surface-border rounded" />
+    </div>
+  );
+}
+
+/** Card sub-shape, shared between `page` and `card` variants. */
+function Card() {
+  return (
+    <div className="bg-surface border border-surface-border rounded-lg p-6">
+      <div className="h-4 w-40 bg-surface-border rounded mb-4" />
+      <div className="space-y-2">
+        <div className="h-3 w-full bg-surface-border rounded" />
+        <div className="h-3 w-11/12 bg-surface-border rounded" />
+        <div className="h-3 w-2/3 bg-surface-border rounded" />
+      </div>
+    </div>
+  );
+}
@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'vitest';
 import { render } from '@testing-library/react';
-import StatusBadge from './StatusBadge';
+import StatusBadge, { statusDisplay, titleCase } from './StatusBadge';

 // -----------------------------------------------------------------------------
 // D-1 master — StatusBadge enum-coverage contract
@@ -118,13 +118,111 @@ describe('StatusBadge — enum-coverage contract (D-1 master)', () => {
    expect(container.querySelector('span')!.className).toContain('badge-warning');
  });

-  // Unknown statuses fall through to neutral. The string is still
-  // displayed verbatim so an operator can see "what is this?" rather
-  // than nothing at all.
-  it('unknown status string renders as neutral but preserves the label text', () => {
+  // Unknown statuses fall through to neutral. The label is humanised
+  // via the titleCase() helper (UX-H5) so the operator sees readable
+  // text rather than the raw enum key — "Some future status" instead
+  // of "SomeFutureStatus".
+  it('unknown status string renders as neutral with titleCase fallback', () => {
    const { container } = render(<StatusBadge status="SomeFutureStatus" />);
    const span = container.querySelector('span');
    expect(span!.className).toBe('badge badge-neutral');
-    expect(span!.textContent).toBe('SomeFutureStatus');
+    expect(span!.textContent).toBe('Some future status');
+  });
+});
+
+// -----------------------------------------------------------------------------
+// UX-H5 master — StatusBadge display-string contract (Phase 1, 2026-05-14)
+//
+// The audit finding: pre-Phase-1, StatusBadge rendered raw Go enum keys
+// — operators saw "RenewalInProgress" / "AwaitingCSR" / "cert_mismatch"
+// / "dead" verbatim. Phase 1 adds a statusDisplay map next to
+// statusStyles; this suite pins the byte-exact display string for every
+// wire key.
+// -----------------------------------------------------------------------------
+describe('StatusBadge — display-string contract (UX-H5)', () => {
+  // Every wire key in the colour map MUST have a display-string entry
+  // and the entry MUST be non-empty. Missing entries fall back to the
+  // titleCase() helper, but having an explicit entry in statusDisplay
+  // is the preferred path (lets us pick the cleanest sentence-case
+  // phrasing, with terms like "Awaiting CSR" capitalised correctly
+  // where titleCase would yield "Awaiting csr").
+  const EXPECTED_DISPLAY: Array<[string, string]> = [
+    // Certificate statuses
+    ['Active', 'Active'],
+    ['Expiring', 'Expiring soon'],
+    ['Expired', 'Expired'],
+    ['RenewalInProgress', 'Renewal in progress'],
+    ['Archived', 'Archived'],
+    ['Revoked', 'Revoked'],
+    // Job statuses
+    ['Pending', 'Pending'],
+    ['AwaitingCSR', 'Awaiting CSR'],
+    ['AwaitingApproval', 'Awaiting approval'],
+    ['Running', 'Running'],
+    ['Completed', 'Completed'],
+    ['Failed', 'Failed'],
+    ['Cancelled', 'Cancelled'],
+    // Agent statuses
+    ['Online', 'Online'],
+    ['Offline', 'Offline'],
+    ['Degraded', 'Degraded'],
+    // Discovery statuses
+    ['Unmanaged', 'Unmanaged'],
+    ['Managed', 'Managed'],
+    ['Dismissed', 'Dismissed'],
+    // Frontend-synthesized issuer statuses
+    ['Enabled', 'Enabled'],
+    ['Disabled', 'Disabled'],
+    // Notification statuses (lowercase wire values)
+    ['sent', 'Sent'],
+    ['pending', 'Pending'],
+    ['failed', 'Failed'],
+    ['dead', 'Dead-lettered'],
+    ['read', 'Read'],
+    // Health check statuses (lowercase + snake_case)
+    ['healthy', 'Healthy'],
+    ['degraded', 'Degraded'],
+    ['down', 'Down'],
+    ['cert_mismatch', 'Certificate mismatch'],
+    ['unknown', 'Unknown'],
+  ];
+
+  it.each(EXPECTED_DISPLAY)(
+    "wire key '%s' renders display string '%s'",
+    (wire, expected) => {
+      // First — verify the statusDisplay map carries the entry verbatim.
+      expect(statusDisplay[wire]).toBe(expected);
+      // Then — verify the rendered <span>'s textContent matches.
+      const { container } = render(<StatusBadge status={wire} />);
+      expect(container.querySelector('span')!.textContent).toBe(expected);
+    },
+  );
+
+  it('every wire key in statusStyles has a matching statusDisplay entry', () => {
+    // Parity check — re-deriving the styles key set isn't possible at
+    // runtime without re-importing it, but we can probe a known sample
+    // and pin: if a future PR adds a new style entry without a display
+    // entry, the EXPECTED_DISPLAY list above will mismatch.
+    expect(Object.keys(statusDisplay).length).toBeGreaterThanOrEqual(
+      EXPECTED_DISPLAY.length,
+    );
+  });
+
+  describe('titleCase() helper — fallback for unmapped keys', () => {
+    it('humanises PascalCase', () => {
+      expect(titleCase('RenewalInProgress')).toBe('Renewal in progress');
+    });
+    it('humanises snake_case', () => {
+      expect(titleCase('cert_mismatch')).toBe('Cert mismatch');
+    });
+    it('handles single-word lowercase', () => {
+      expect(titleCase('pending')).toBe('Pending');
+    });
+    it('handles single-word PascalCase', () => {
+      expect(titleCase('Active')).toBe('Active');
+    });
+    it('handles empty string defensively', () => {
+      expect(titleCase('')).toBe('');
+    });
  });
 });
@@ -4,6 +4,16 @@
 // the Go side; StatusBadge.test.tsx walks every value and will go red
 // before users see a default-grey "what is happening?" badge.
 //
+// UX-H5 closure (Phase 1, 2026-05-14): we now render a human display
+// string rather than the raw enum key. The wire keys stay byte-
+// identical to the Go-side enums (per the D-1 closure comment above) —
+// only the rendered text changes. PascalCase + snake_case +
+// lowercase enums map to spaced sentence-case ("Renewal in progress",
+// "Awaiting CSR", "Dead-lettered", "Certificate mismatch"). Unmapped
+// keys fall through to a titleCase helper that lower-bounds the
+// readability even when a new Go-side enum lands before the frontend
+// catches up.
+//
 // D-1 master closure (cat-d-359e92c20cbf, cat-d-9f4c8e4a91f1,
 // cat-d-1447e04732e7, cat-f-cert_detail_page_key_render_fallback,
 // cat-f-ae0d06b6588f) fixed the pre-master drift:
@@ -74,7 +84,73 @@ const statusStyles: Record<string, string> = {
  unknown:             'badge-neutral',
 };

+// statusDisplay — human-facing text for each wire key. UX-H5 closure.
+// Keys MUST stay byte-identical to statusStyles above (which is byte-
+// identical to the Go enums). When a key here is missing, the
+// titleCase fallback below renders something readable rather than
+// the raw enum key.
+const statusDisplay: Record<string, string> = {
+  // Certificate statuses
+  Active:              'Active',
+  Expiring:            'Expiring soon',
+  Expired:             'Expired',
+  RenewalInProgress:   'Renewal in progress',
+  Archived:            'Archived',
+  Revoked:             'Revoked',
+  // Job statuses
+  Pending:             'Pending',
+  AwaitingCSR:         'Awaiting CSR',
+  AwaitingApproval:    'Awaiting approval',
+  Running:             'Running',
+  Completed:           'Completed',
+  Failed:              'Failed',
+  Cancelled:           'Cancelled',
+  // Agent statuses
+  Online:              'Online',
+  Offline:             'Offline',
+  Degraded:            'Degraded',
+  // Discovery statuses
+  Unmanaged:           'Unmanaged',
+  Managed:             'Managed',
+  Dismissed:           'Dismissed',
+  // Issuer statuses (frontend-synthesized)
+  Enabled:             'Enabled',
+  Disabled:            'Disabled',
+  // Notification statuses
+  sent:                'Sent',
+  pending:             'Pending',
+  failed:              'Failed',
+  dead:                'Dead-lettered',
+  read:                'Read',
+  // Health check statuses
+  healthy:             'Healthy',
+  degraded:            'Degraded',
+  down:                'Down',
+  cert_mismatch:       'Certificate mismatch',
+  unknown:             'Unknown',
+};
+
+// titleCase — best-effort humanizer for wire keys not in statusDisplay.
+// Handles PascalCase ("RenewalInProgress" → "Renewal in progress") and
+// snake_case ("cert_mismatch" → "Cert mismatch"). The render-time fallback;
+// adding a proper entry to statusDisplay above is the preferred path.
+function titleCase(s: string): string {
+  if (!s) return s;
+  // snake_case → space-separated lower
+  let out = s.replace(/_/g, ' ');
+  // PascalCase / camelCase → space before capitals (but not the first)
+  out = out.replace(/([a-z])([A-Z])/g, '$1 $2');
+  // Lowercase everything, then capitalize the first character.
+  out = out.toLowerCase();
+  return out.charAt(0).toUpperCase() + out.slice(1);
+}
+
 export default function StatusBadge({ status }: { status: string }) {
  const cls = statusStyles[status] || 'badge-neutral';
-  return <span className={`badge ${cls}`}>{status}</span>;
+  const display = statusDisplay[status] ?? titleCase(status);
+  return <span className={`badge ${cls}`}>{display}</span>;
 }
+
+// Exported for the StatusBadge.test.tsx suite — pinning the byte-exact
+// display strings for every wire key in one place.
+export { statusStyles, statusDisplay, titleCase };
@@ -0,0 +1,54 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import { render, screen } from '@testing-library/react';
+import Timestamp from './Timestamp';
+import { setTimestampPref, getTimestampPref } from '../api/timestampPref';
+
+const ISO = '2026-05-14T15:30:00Z';
+
+describe('Timestamp', () => {
+  beforeEach(() => {
+    // Reset preference between tests.
+    localStorage.clear();
+  });
+
+  it('renders em-dash for empty iso, no tooltip wrapper', () => {
+    render(<Timestamp iso={null} />);
+    expect(screen.getByText('—')).toBeInTheDocument();
+  });
+
+  it('default preference is UTC + appends " UTC" suffix', () => {
+    render(<Timestamp iso={ISO} />);
+    // Default localStorage is empty → mode='utc'.
+    expect(getTimestampPref().mode).toBe('utc');
+    // 2026-05-14T15:30:00Z formatted in UTC contains May 14 15:30.
+    const text = screen.getByText(/UTC/);
+    expect(text.textContent).toMatch(/2026/);
+    expect(text.textContent).toMatch(/15:30|3:30/);
+  });
+
+  it('forceMode="utc" overrides operator local preference', () => {
+    setTimestampPref({ mode: 'local', customTz: 'UTC' });
+    render(<Timestamp iso={ISO} forceMode="utc" />);
+    expect(screen.getByText(/UTC/)).toBeInTheDocument();
+  });
+
+  it('mode="local" renders without UTC suffix', () => {
+    setTimestampPref({ mode: 'local', customTz: 'UTC' });
+    render(<Timestamp iso={ISO} />);
+    // Local mode strips the " UTC" suffix from the visible span.
+    const all = screen.getAllByText(/2026/);
+    const visible = all.find(el => !el.textContent?.includes('UTC'));
+    expect(visible).toBeDefined();
+  });
+
+  it('mode="custom" renders the timezone label in parens', () => {
+    setTimestampPref({ mode: 'custom', customTz: 'America/New_York' });
+    render(<Timestamp iso={ISO} />);
+    expect(screen.getByText(/America\/New_York/)).toBeInTheDocument();
+  });
+
+  it('invalid custom tz falls back to UTC under the hood (no throw)', () => {
+    setTimestampPref({ mode: 'custom', customTz: 'Not/Real_Zone' });
+    expect(() => render(<Timestamp iso={ISO} />)).not.toThrow();
+  });
+});
@@ -0,0 +1,90 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Timestamp — Phase 6 closure for I18N-H3 (zero timezone handling
+// today; server UTC audit logs can't be cross-referenced with frontend
+// display without operator math).
+//
+// Default behavior: render the timestamp in UTC (so what the operator
+// sees on-screen is byte-for-byte equivalent to what they'll grep out
+// of `audit_events.created_at` or `journalctl -u certctl`), wrap it in
+// the Phase 1 Tooltip primitive that surfaces the operator-local
+// equivalent on hover / focus.
+//
+// Operator preference (`certctl:timestamp-display` in localStorage,
+// see api/timestampPref.ts) flips the default. Available modes:
+//   • utc       — render UTC, hover shows local. The safe default.
+//   • local     — render browser-local, hover shows UTC.
+//   • custom    — render in a configured IANA timezone, hover shows UTC.
+//
+// Why this lives as a primitive: pre-Phase-6, ~8 raw new Date(x)
+// .toLocaleString() sites across 6 pages each made their own choice.
+// Phase 6 routes them all through this one component + the CI guard
+// at scripts/ci-guards/no-raw-toLocaleString.sh prevents new raw sites.
+
+import { useEffect, useState } from 'react';
+import Tooltip from './Tooltip';
+import { formatDateTime, formatDateTimeUTC, formatDateTimeInZone } from '../api/utils';
+import { getTimestampPref, type TimestampPref } from '../api/timestampPref';
+
+interface TimestampProps {
+  /** ISO-8601 timestamp from the API. Falsy renders an em-dash. */
+  iso: string | undefined | null;
+  /**
+   * Override the operator preference for this one site — usually
+   * unset. Set to 'utc' when the visible label MUST be UTC (e.g.
+   * inside an audit-log column where the column header says "UTC").
+   */
+  forceMode?: 'utc' | 'local';
+  /** Optional class for the visible span. */
+  className?: string;
+}
+
+function render(iso: string | undefined | null, pref: TimestampPref, forceMode?: 'utc' | 'local'): {
+  visible: string;
+  hover: string;
+} {
+  if (!iso) return { visible: '—', hover: '—' };
+  const mode = forceMode ?? pref.mode;
+  if (mode === 'utc') {
+    return { visible: formatDateTimeUTC(iso) + ' UTC', hover: formatDateTime(iso) + ' (local)' };
+  }
+  if (mode === 'local') {
+    return { visible: formatDateTime(iso), hover: formatDateTimeUTC(iso) + ' UTC' };
+  }
+  // mode === 'custom'
+  return {
+    visible: formatDateTimeInZone(iso, pref.customTz) + ' (' + pref.customTz + ')',
+    hover: formatDateTimeUTC(iso) + ' UTC',
+  };
+}
+
+export default function Timestamp({ iso, forceMode, className }: TimestampProps) {
+  // Initialize from localStorage at mount time so SSR-style empty
+  // renders don't flash the wrong format on first paint.
+  const [pref, setPref] = useState<TimestampPref>(() => getTimestampPref());
+
+  // Live-update when the operator changes the preference on the
+  // Settings page. timestampPref.ts dispatches a CustomEvent we
+  // subscribe to here.
+  useEffect(() => {
+    function onChange(e: Event) {
+      const detail = (e as CustomEvent<TimestampPref>).detail;
+      if (detail) setPref(detail);
+    }
+    window.addEventListener('certctl:timestamp-pref-changed', onChange);
+    return () => window.removeEventListener('certctl:timestamp-pref-changed', onChange);
+  }, []);
+
+  const { visible, hover } = render(iso, pref, forceMode);
+
+  if (!iso) {
+    return <span className={className}>{visible}</span>;
+  }
+
+  return (
+    <Tooltip content={hover}>
+      <span className={className}>{visible}</span>
+    </Tooltip>
+  );
+}
@@ -0,0 +1,41 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Smoke-test the Toaster wrapper. Sonner has its own deep test suite;
+// we just pin (a) the wrapper renders without crashing, (b) the
+// Sonner <Toaster /> root lands in the DOM with our position prop, and
+// (c) toast.success / toast.error reach the renderer.
+
+import { render, screen, act } from '@testing-library/react';
+import { describe, it, expect } from 'vitest';
+import { toast } from 'sonner';
+import Toaster from './Toaster';
+
+describe('Toaster', () => {
+  it('renders the Sonner root without crashing', () => {
+    render(<Toaster />);
+    // Sonner mounts a section[aria-label="Notifications <kbd>"] container
+    // — the label includes Sonner's expand-shortcut hint (e.g. "alt+T").
+    // Match the prefix only.
+    expect(screen.getByLabelText(/Notifications/)).toBeInTheDocument();
+  });
+
+  it('forwards toast.success() to the visible queue', async () => {
+    render(<Toaster />);
+    act(() => {
+      toast.success('Profile saved');
+    });
+    // Sonner debounces render slightly; flush via findByText.
+    expect(await screen.findByText('Profile saved')).toBeInTheDocument();
+  });
+
+  it('forwards toast.error() to the visible queue', async () => {
+    render(<Toaster />);
+    act(() => {
+      toast.error('Save failed: not authorized');
+    });
+    expect(
+      await screen.findByText('Save failed: not authorized'),
+    ).toBeInTheDocument();
+  });
+});
@@ -0,0 +1,43 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Toaster — the certctl-themed Sonner wrapper. Phase 1 closure for
+// UX-H3 (no toast / snackbar system) per the frontend-design-audit.
+//
+// Mount once near the top of <main.tsx>'s React tree (next to
+// QueryClientProvider). Inside any component, import { toast } from
+// "sonner" and call toast.success(…) / toast.error(…) / toast.info(…) /
+// toast.warning(…). Sonner handles the singleton queue, focus + ARIA
+// (role="status" / role="alert"), enter/exit animation, swipe-to-
+// dismiss, and respects prefers-reduced-motion automatically.
+//
+// We surface a thin wrapper rather than the bare <Toaster /> so the
+// default position + visual config lives in one place. Pages must NOT
+// mount their own Toaster instances — Sonner asserts at runtime if
+// multiple are mounted, but the failure mode is "toasts duplicate or
+// disappear silently" which is hard to debug. Single import discipline.
+//
+// Visual position: top-right. Operators are paginated-table-heavy;
+// top-right keeps the toast away from row-action click targets at the
+// bottom of the list. richColors gives us the per-severity background
+// fills (success teal / error red / warning amber / info blue) that
+// match the existing .badge-* color tier.
+
+import { Toaster as SonnerToaster } from 'sonner';
+
+export default function Toaster() {
+  return (
+    <SonnerToaster
+      position="top-right"
+      richColors
+      closeButton
+      // 4s default for non-action toasts; persistent for error toasts
+      // with action (set per-call via toast.error(msg, { duration: ... })).
+      duration={4000}
+      // visibleToasts: cap stack so a runaway error loop doesn't drown
+      // the screen. 5 is the Sonner default; pinning it explicitly so
+      // the choice is documented.
+      visibleToasts={5}
+    />
+  );
+}
@@ -0,0 +1,49 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Tooltip smoke + interaction tests. Floating-UI's positioning math
+// requires a real browser layout engine; we just assert the wiring:
+//   - children render at rest (no tooltip)
+//   - focus reveals the tooltip body in the portal
+//   - escape dismisses
+
+import { render, screen, fireEvent } from '@testing-library/react';
+import { describe, it, expect } from 'vitest';
+import Tooltip from './Tooltip';
+
+describe('Tooltip', () => {
+  it('renders the trigger at rest with no tooltip visible', () => {
+    render(
+      <Tooltip content="Hint">
+        <button>Hover me</button>
+      </Tooltip>,
+    );
+    expect(screen.getByRole('button', { name: 'Hover me' })).toBeInTheDocument();
+    expect(screen.queryByText('Hint')).not.toBeInTheDocument();
+  });
+
+  it('reveals tooltip body on focus', () => {
+    render(
+      <Tooltip content="Hint visible">
+        <button>Focusable trigger</button>
+      </Tooltip>,
+    );
+    const trigger = screen.getByRole('button', { name: 'Focusable trigger' });
+    fireEvent.focus(trigger);
+    // FloatingPortal renders into document.body; queryable.
+    expect(screen.getByText('Hint visible')).toBeInTheDocument();
+  });
+
+  it('dismisses on Escape after focus-open', () => {
+    render(
+      <Tooltip content="Press escape">
+        <button>Focusable</button>
+      </Tooltip>,
+    );
+    const trigger = screen.getByRole('button', { name: 'Focusable' });
+    fireEvent.focus(trigger);
+    expect(screen.getByText('Press escape')).toBeInTheDocument();
+    fireEvent.keyDown(document, { key: 'Escape' });
+    expect(screen.queryByText('Press escape')).not.toBeInTheDocument();
+  });
+});
@@ -0,0 +1,122 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Tooltip — Floating-UI-backed replacement for the ~103 native title=
+// attributes. Phase 1 builds the primitive; migrating the 103 callsites
+// is per-page rolling work that happens in subsequent PRs (per the
+// audit prompt's explicit "DO NOT" on one-mega-PR sweeps).
+//
+// Why Floating-UI: native title= renders poorly on mobile + has no
+// reliable show/hide timing, no visual styling, no positioning around
+// the edges of the viewport, and (most importantly) zero a11y story
+// beyond the browser's default tooltip — which screen readers
+// inconsistently surface. Floating-UI gives us:
+//   - middleware-driven positioning (auto-flip, shift, offset)
+//   - hover + focus triggers (with `useFocus` + `useHover`)
+//   - aria-describedby wiring via `useRole`
+//   - dismissable via ESC
+//
+// Usage:
+//   <Tooltip content="Some hint">
+//     <button>Hover me</button>
+//   </Tooltip>
+//
+// Children must be a single element capable of accepting a ref. For
+// non-ref-forwardable children (e.g. plain text), wrap in a span.
+
+import { useState, cloneElement, isValidElement } from 'react';
+import type { ReactElement, ReactNode } from 'react';
+import {
+  useFloating,
+  useHover,
+  useFocus,
+  useDismiss,
+  useRole,
+  useInteractions,
+  flip,
+  shift,
+  offset,
+  autoUpdate,
+  FloatingPortal,
+} from '@floating-ui/react';
+
+export interface TooltipProps {
+  /** Tooltip body — usually a short string; ReactNode is allowed for icons. */
+  content: ReactNode;
+  /** Single child element that receives the ref + ARIA wiring. */
+  children: ReactElement;
+  /** Preferred placement; Floating-UI will auto-flip if viewport-clamped. */
+  placement?: 'top' | 'right' | 'bottom' | 'left';
+  /** Pixel offset between the trigger and the tooltip. Default 6. */
+  offsetPx?: number;
+}
+
+export default function Tooltip({
+  content,
+  children,
+  placement = 'top',
+  offsetPx = 6,
+}: TooltipProps) {
+  const [open, setOpen] = useState(false);
+
+  const { refs, floatingStyles, context } = useFloating({
+    open,
+    onOpenChange: setOpen,
+    placement,
+    middleware: [offset(offsetPx), flip(), shift({ padding: 8 })],
+    whileElementsMounted: autoUpdate,
+  });
+
+  const hover = useHover(context, { move: false, delay: { open: 200, close: 0 } });
+  const focus = useFocus(context);
+  const dismiss = useDismiss(context);
+  const role = useRole(context, { role: 'tooltip' });
+
+  const { getReferenceProps, getFloatingProps } = useInteractions([
+    hover,
+    focus,
+    dismiss,
+    role,
+  ]);
+
+  if (!isValidElement(children)) {
+    // Defensive: render the child verbatim; Tooltip wiring is skipped.
+    // Console-warn so the misuse is visible during dev.
+    if (typeof console !== 'undefined') {
+      console.warn(
+        '<Tooltip> requires a single React element child; got:',
+        children,
+      );
+    }
+    return <>{children}</>;
+  }
+
+  // Merge the ref + interaction props onto the child. cloneElement keeps
+  // the original child's type + own props; we layer ours on top.
+  const triggerProps = getReferenceProps();
+  const child = cloneElement(
+    children as ReactElement<Record<string, unknown>>,
+    {
+      ref: refs.setReference,
+      ...triggerProps,
+    },
+  );
+
+  return (
+    <>
+      {child}
+      {open && content && (
+        <FloatingPortal>
+          <div
+            ref={refs.setFloating}
+            style={floatingStyles}
+            {...getFloatingProps()}
+            className="z-50 max-w-xs rounded bg-ink/95 text-white text-xs px-2 py-1 shadow-lg pointer-events-none"
+          >
+            {content}
+          </div>
+        </FloatingPortal>
+      )}
+    </>
+  );
+}
@@ -21,7 +21,7 @@
 // JobsPage, RenewalPoliciesPage, DiscoveryPage) are deferred to a
 // follow-up bundle — tracked as new ID `M-029`.

-import { useCallback, useMemo } from 'react';
+import { useCallback, useMemo, useTransition } from 'react';
 import { useSearchParams } from 'react-router-dom';

 export interface ListParams {
@@ -56,6 +56,13 @@ const DEFAULT_PAGE_SIZE = 25;
 */
 export function useListParams(defaults?: Partial<ListParams>): ListParamsControls {
  const [searchParams, setSearchParams] = useSearchParams();
+  // Phase 4 closure (PERF-M1): mark URL-resident filter / sort / page
+  // updates as a transition so React can preempt the result-table
+  // reconciliation when the operator interacts with the toolbar (e.g.
+  // rapidly toggling dropdowns while a 50-row table is still rendering
+  // the previous result). useTransition keeps the dropdown UI snappy
+  // even when the result render is expensive.
+  const [, startTransition] = useTransition();

  const params = useMemo<ListParams>(() => {
    const page = parsePositiveInt(searchParams.get('page'), defaults?.page ?? DEFAULT_PAGE);
@@ -88,7 +95,14 @@ export function useListParams(defaults?: Partial<ListParams>): ListParamsControl
      if (key !== 'page') {
        next.delete('page');
      }
-      setSearchParams(next, { replace: true });
+      // startTransition lets React mark the downstream table reconcile
+      // as low-priority work — urgent updates (input typing, button
+      // hover) can preempt. The URL itself still updates immediately
+      // because setSearchParams calls history.replaceState synchronously;
+      // only the React-tree reconciliation is deferred.
+      startTransition(() => {
+        setSearchParams(next, { replace: true });
+      });
    },
    [searchParams, setSearchParams],
  );
@@ -80,4 +80,116 @@ describe('useTrackedMutation — Bundle-8 / M-009', () => {
    expect(invalidateSpy).not.toHaveBeenCalled();
    expect(onSuccess).toHaveBeenCalledOnce();
  });
+
+  // Phase 2 TQ-L1 extension — pin the optimistic-update contract.
+  //
+  // useTrackedMutation passes onMutate / onError / onSettled through
+  // verbatim (only onSuccess is wrapper-owned). The 4 Phase-2 sites
+  // (mark-notification-read, dismiss-discovery, claim-discovered,
+  // archive-certificate) depend on this pass-through to implement
+  // optimistic updates with rollback. These tests pin:
+  //   (a) onMutate runs before mutationFn (snapshot pre-mutation state)
+  //   (b) onError fires with the snapshot as the 3rd arg (rollback path)
+  //   (c) onError pass-through (raw useMutation behaviour preserved)
+  //   (d) the no-options call is parity with raw useMutation (the
+  //       wrapper imposes no semantic behaviour beyond invalidation
+  //       + the optional onSuccess chain).
+  it('passes onMutate through and runs it before mutationFn', async () => {
+    const client = new QueryClient();
+    const order: string[] = [];
+    const { result } = renderHook(
+      () =>
+        useTrackedMutation({
+          mutationFn: async () => {
+            order.push('mutate');
+            return 'ok';
+          },
+          invalidates: [['something']],
+          onMutate: async () => {
+            order.push('onMutate');
+            return { snapshot: 'pre-state' };
+          },
+        }),
+      { wrapper: withQueryClient(client) },
+    );
+    result.current.mutate(undefined);
+    await waitFor(() => expect(result.current.isSuccess).toBe(true));
+    expect(order).toEqual(['onMutate', 'mutate']);
+  });
+
+  it('passes onError through with the onMutate context (rollback path)', async () => {
+    const client = new QueryClient();
+    const onError = vi.fn();
+    const onMutate = vi.fn(async () => ({ snapshot: { foo: 'bar' } }));
+    const { result } = renderHook(
+      () =>
+        useTrackedMutation({
+          mutationFn: async () => {
+            throw new Error('boom');
+          },
+          invalidates: [['something']],
+          onMutate,
+          onError,
+        }),
+      { wrapper: withQueryClient(client) },
+    );
+    result.current.mutate(undefined);
+    await waitFor(() => expect(result.current.isError).toBe(true));
+    expect(onMutate).toHaveBeenCalledOnce();
+    expect(onError).toHaveBeenCalledOnce();
+    // 3rd arg of onError is the onMutate return value (the snapshot
+    // for rollback). Pinning this guarantees the optimistic-update
+    // rollback wiring stays intact across future refactors.
+    expect(onError.mock.calls[0][2]).toEqual({ snapshot: { foo: 'bar' } });
+  });
+
+  it('does NOT invalidate on error (only on success)', async () => {
+    const client = new QueryClient();
+    const invalidateSpy = vi.spyOn(client, 'invalidateQueries');
+    const { result } = renderHook(
+      () =>
+        useTrackedMutation({
+          mutationFn: async () => {
+            throw new Error('nope');
+          },
+          invalidates: [['cache-key']],
+        }),
+      { wrapper: withQueryClient(client) },
+    );
+    result.current.mutate(undefined);
+    await waitFor(() => expect(result.current.isError).toBe(true));
+    expect(invalidateSpy).not.toHaveBeenCalled();
+  });
+
+  it('passes onSettled through (fires after both success and error)', async () => {
+    const client = new QueryClient();
+    const onSettled = vi.fn();
+    const { result } = renderHook(
+      () =>
+        useTrackedMutation({
+          mutationFn: async () => 'ok',
+          invalidates: [['x']],
+          onSettled,
+        }),
+      { wrapper: withQueryClient(client) },
+    );
+    result.current.mutate(undefined);
+    await waitFor(() => expect(result.current.isSuccess).toBe(true));
+    expect(onSettled).toHaveBeenCalledOnce();
+  });
+
+  it('parity with raw useMutation when no extra options given', async () => {
+    const client = new QueryClient();
+    const { result } = renderHook(
+      () =>
+        useTrackedMutation({
+          mutationFn: async (n: number) => n * 2,
+          invalidates: [['compute']],
+        }),
+      { wrapper: withQueryClient(client) },
+    );
+    result.current.mutate(7);
+    await waitFor(() => expect(result.current.isSuccess).toBe(true));
+    expect(result.current.data).toBe(14);
+  });
 });
@@ -1,4 +1,12 @@
-@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600&display=swap');
+/*
+ * Phase 0 hygiene (FE-H4 / PERF-H3): Inter + JetBrains Mono are now
+ * self-hosted via the @fontsource* packages, imported at the top of
+ * web/src/main.tsx so Vite can hash + bundle the font files. The old
+ * Google Fonts @import lived here and produced two cross-origin font
+ * requests on every cold load; those are gone and PERF-H3's
+ * preconnect/dns-prefetch suggestion collapses (no external host left
+ * to preconnect to).
+ */

@tailwind base;
@tailwind components;
@@ -7,7 +15,11 @@
@layer base {
  body {
    @apply bg-page text-ink antialiased;
-    font-family: 'Inter', system-ui, -apple-system, sans-serif;
+    /* Phase 0 hygiene (FE-H4): "Inter Variable" is the family name
+       registered by @fontsource-variable/inter (single woff2 covering
+       wght 100-900). Keep "Inter" as a fallback for older browsers /
+       any pinned local install. */
+    font-family: 'Inter Variable', 'Inter', system-ui, -apple-system, sans-serif;
  }
 }

@@ -51,3 +63,79 @@
    @apply bg-surface border border-surface-border rounded-md shadow-sm p-5 border-t-4;
  }
 }
+
+/*
+ * Phase 0 hygiene (UX-L2): honour prefers-reduced-motion. Users who
+ * opt out of animation at the OS level get effectively-instant
+ * transitions on every animated element (badges, modals, toggles).
+ * 0.01ms is the conventional non-zero value — fully zero can break
+ * libraries that observe transitionend events.
+ */
+@media (prefers-reduced-motion: reduce) {
+  *,
+  ::before,
+  ::after {
+    animation-duration: 0.01ms !important;
+    animation-iteration-count: 1 !important;
+    transition-duration: 0.01ms !important;
+    scroll-behavior: auto !important;
+  }
+}
+
+/*
+ * Phase 0 hygiene (UX-L3): a baseline print stylesheet. Hides the
+ * sidebar + top action bars, removes card shadows, expands content
+ * to full width, and keeps table rows intact across page breaks.
+ * Operator-facing — operators print certificate detail pages and
+ * audit-log exports for compliance archives.
+ */
+@media print {
+  /* Drop sidebar / nav chrome — only the content matters in print. */
+  aside,
+  nav,
+  [role="navigation"],
+  .no-print {
+    display: none !important;
+  }
+
+  /* Full-width content, no shadows, plain backgrounds (ink saving). */
+  body {
+    background: #ffffff !important;
+    color: #000000 !important;
+  }
+  main,
+  .card,
+  .stat-card {
+    width: 100% !important;
+    max-width: 100% !important;
+    margin: 0 !important;
+    box-shadow: none !important;
+    border-color: #cbd5e1 !important;
+    page-break-inside: avoid;
+  }
+
+  /* Tables: prevent mid-row breaks, repeat headers on each page. */
+  table {
+    width: 100% !important;
+  }
+  thead {
+    display: table-header-group;
+  }
+  tr,
+  td,
+  th {
+    page-break-inside: avoid;
+  }
+
+  /* Show link hrefs alongside the visible text — print readers
+     can't click links, so the target URL is the only signal. */
+  a[href]::after {
+    content: " (" attr(href) ")";
+    font-size: 0.85em;
+    color: #555555;
+  }
+  a[href^="#"]::after,
+  a[href^="javascript:"]::after {
+    content: "";
+  }
+}
@@ -1,4 +1,13 @@
-import { StrictMode } from 'react';
+// Phase 0 hygiene (FE-H4 / PERF-H3): self-hosted fonts. Replaces the
+// Google Fonts @import that used to live at the top of src/index.css —
+// Vite hashes + bundles these CSS files into web/dist on build, so cold
+// loads no longer touch fonts.googleapis.com / fonts.gstatic.com.
+import '@fontsource-variable/inter';
+import '@fontsource/jetbrains-mono/400.css';
+import '@fontsource/jetbrains-mono/500.css';
+import '@fontsource/jetbrains-mono/600.css';
+
+import { StrictMode, Suspense, lazy } from 'react';
 import { createRoot } from 'react-dom/client';
 import { BrowserRouter, Routes, Route } from 'react-router-dom';
 import { QueryClient, QueryClientProvider } from '@tanstack/react-query';
@@ -6,101 +15,170 @@ import ErrorBoundary from './components/ErrorBoundary';
 import AuthProvider from './components/AuthProvider';
 import AuthGate from './components/AuthGate';
 import Layout from './components/Layout';
+// Phase 4 closure (FE-M5 + SCALE-H1): per-route code splitting.
+// Pre-Phase-4 every page import above was eager — every page's React
+// tree + its api/client + its query-key constants + its chart panels
+// landed in the same first-load index-*.js (~1.07 MB raw / ~281 KB gz).
+//
+// Post-Phase-4 the dashboard stays eager (it's the landing route for
+// every cold load) and every other page becomes a React.lazy() boundary
+// so its chunk only ships when an operator navigates to that route.
+// Each route is wrapped in a <Suspense fallback={<Skeleton variant=
+// "page" />}> so the route transition shows a page-shaped skeleton
+// instead of a blank white frame during the chunk fetch.
+//
+// Vite's manualChunks config (see vite.config.ts) splits react /
+// react-router-dom / @tanstack/react-query / recharts / lucide-react
+// into their own vendor chunks so vendor caches survive feature
+// deploys (the index-*.js hash flips on every feature change; vendor
+// chunks only re-hash when their package versions change in
+// package-lock.json).
+//
+// Net cold-load budget post-Phase-4: vendor-react + vendor-router +
+// vendor-query + (per-route chunk) + index-*.js (now only the routing
+// + provider plumbing, not the page bodies). Dashboard adds
+// vendor-recharts on demand.
 import DashboardPage from './pages/DashboardPage';
-import CertificatesPage from './pages/CertificatesPage';
-import CertificateDetailPage from './pages/CertificateDetailPage';
-import AgentsPage from './pages/AgentsPage';
-import AgentDetailPage from './pages/AgentDetailPage';
-import JobsPage from './pages/JobsPage';
-import NotificationsPage from './pages/NotificationsPage';
-import PoliciesPage from './pages/PoliciesPage';
-import RenewalPoliciesPage from './pages/RenewalPoliciesPage';
-import IssuersPage from './pages/IssuersPage';
-import TargetsPage from './pages/TargetsPage';
-import ProfilesPage from './pages/ProfilesPage';
-import OwnersPage from './pages/OwnersPage';
-import TeamsPage from './pages/TeamsPage';
-import AgentGroupsPage from './pages/AgentGroupsPage';
-import AuditPage from './pages/AuditPage';
-import ShortLivedPage from './pages/ShortLivedPage';
-import AgentFleetPage from './pages/AgentFleetPage';
-import DiscoveryPage from './pages/DiscoveryPage';
-import NetworkScanPage from './pages/NetworkScanPage';
-import HealthMonitorPage from './pages/HealthMonitorPage';
-import DigestPage from './pages/DigestPage';
-import ObservabilityPage from './pages/ObservabilityPage';
-import JobDetailPage from './pages/JobDetailPage';
-import IssuerDetailPage from './pages/IssuerDetailPage';
-import IssuerHierarchyPage from './pages/IssuerHierarchyPage';
-import TargetDetailPage from './pages/TargetDetailPage';
-import SCEPAdminPage from './pages/SCEPAdminPage';
-import ESTAdminPage from './pages/ESTAdminPage';
-// Bundle 1 Phase 10 — RBAC management pages.
-import RolesPage from './pages/auth/RolesPage';
-import RoleDetailPage from './pages/auth/RoleDetailPage';
-import KeysPage from './pages/auth/KeysPage';
-import AuthSettingsPage from './pages/auth/AuthSettingsPage';
-import ApprovalsPage from './pages/auth/ApprovalsPage';
-// Bundle 2 Phase 8 — OIDC + session management pages.
-import OIDCProvidersPage from './pages/auth/OIDCProvidersPage';
-import OIDCProviderDetailPage from './pages/auth/OIDCProviderDetailPage';
-import GroupMappingsPage from './pages/auth/GroupMappingsPage';
-import SessionsPage from './pages/auth/SessionsPage';
-import BreakglassPage from './pages/auth/BreakglassPage';
-// Audit 2026-05-10 MED-11 closure — federated-user admin page.
-import UsersPage from './pages/auth/UsersPage';
+import Skeleton from './components/Skeleton';
+
+// Inventory.
+const CertificatesPage      = lazy(() => import('./pages/CertificatesPage'));
+const CertificateDetailPage = lazy(() => import('./pages/CertificateDetailPage'));
+const IssuersPage           = lazy(() => import('./pages/IssuersPage'));
+const IssuerDetailPage      = lazy(() => import('./pages/IssuerDetailPage'));
+const IssuerHierarchyPage   = lazy(() => import('./pages/IssuerHierarchyPage'));
+const TargetsPage           = lazy(() => import('./pages/TargetsPage'));
+const TargetDetailPage      = lazy(() => import('./pages/TargetDetailPage'));
+const ProfilesPage          = lazy(() => import('./pages/ProfilesPage'));
+// Delivery & jobs.
+const JobsPage              = lazy(() => import('./pages/JobsPage'));
+const JobDetailPage         = lazy(() => import('./pages/JobDetailPage'));
+const AgentsPage            = lazy(() => import('./pages/AgentsPage'));
+const AgentDetailPage       = lazy(() => import('./pages/AgentDetailPage'));
+const AgentFleetPage        = lazy(() => import('./pages/AgentFleetPage'));
+const AgentGroupsPage       = lazy(() => import('./pages/AgentGroupsPage'));
+// Policy & notify.
+const PoliciesPage          = lazy(() => import('./pages/PoliciesPage'));
+const RenewalPoliciesPage   = lazy(() => import('./pages/RenewalPoliciesPage'));
+const NotificationsPage     = lazy(() => import('./pages/NotificationsPage'));
+const DigestPage            = lazy(() => import('./pages/DigestPage'));
+// People.
+const OwnersPage            = lazy(() => import('./pages/OwnersPage'));
+const TeamsPage             = lazy(() => import('./pages/TeamsPage'));
+// Audit & ops.
+const AuditPage             = lazy(() => import('./pages/AuditPage'));
+const ShortLivedPage        = lazy(() => import('./pages/ShortLivedPage'));
+const DiscoveryPage         = lazy(() => import('./pages/DiscoveryPage'));
+const NetworkScanPage       = lazy(() => import('./pages/NetworkScanPage'));
+const HealthMonitorPage     = lazy(() => import('./pages/HealthMonitorPage'));
+const ObservabilityPage     = lazy(() => import('./pages/ObservabilityPage'));
+// Protocol admin.
+const SCEPAdminPage         = lazy(() => import('./pages/SCEPAdminPage'));
+const ESTAdminPage          = lazy(() => import('./pages/ESTAdminPage'));
+// Access (Bundle 1 Phase 10 — RBAC management).
+const RolesPage             = lazy(() => import('./pages/auth/RolesPage'));
+const RoleDetailPage        = lazy(() => import('./pages/auth/RoleDetailPage'));
+const KeysPage              = lazy(() => import('./pages/auth/KeysPage'));
+const AuthSettingsPage      = lazy(() => import('./pages/auth/AuthSettingsPage'));
+const ApprovalsPage         = lazy(() => import('./pages/auth/ApprovalsPage'));
+// Access (Bundle 2 Phase 8 — OIDC + session management).
+const OIDCProvidersPage     = lazy(() => import('./pages/auth/OIDCProvidersPage'));
+const OIDCProviderDetailPage = lazy(() => import('./pages/auth/OIDCProviderDetailPage'));
+const GroupMappingsPage     = lazy(() => import('./pages/auth/GroupMappingsPage'));
+const SessionsPage          = lazy(() => import('./pages/auth/SessionsPage'));
+const BreakglassPage        = lazy(() => import('./pages/auth/BreakglassPage'));
+// Audit 2026-05-10 MED-11 closure — federated-user admin.
+const UsersPage             = lazy(() => import('./pages/auth/UsersPage'));
+
+// Phase 1 closure (UX-H3): toast / snackbar system. Mounted once near
+// the root so any component can `import { toast } from "sonner"` and
+// call toast.success / toast.error without provider plumbing.
+import Toaster from './components/Toaster';
+// Phase 3 closure (UX-H6 + FE-L4): cmd+k command palette mounted at
+// the root. The hook + listener live in CommandPaletteHost so the
+// keydown binding stays scoped to the React tree (auto-cleanup on
+// HMR + StrictMode).
+import CommandPaletteHost from './components/CommandPaletteHost';
+import { STALE_TIME, GC_TIME } from './api/queryConstants';
 import './index.css';

+// Phase 2 closure (TQ-H2 + TQ-M1): QueryClient defaults rewritten.
+// Pre-Phase-2: staleTime 10s + refetchOnWindowFocus true caused a
+// refetch storm on every tab refocus across 242 query sites and a
+// 10s "freshness" window meaning every cross-page navigation
+// triggered backend hits.
+//
+// Post-Phase-2: 5min REFERENCE staleTime is the dominant-case sane
+// default; queries that legitimately need live data (jobs, in-flight
+// scans, agent heartbeats — the live-tile cohort) opt in PER-QUERY to
+// staleTime: STALE_TIME.REAL_TIME + refetchOnWindowFocus: true. gcTime
+// is now explicit at STANDARD (5min) so the contract is documented at
+// the root rather than implicit-defaulted by TanStack.
+//
+// retry: 1 stays — lowering to 0 surfaces network blips; raising to
+// the TanStack default of 3 hammers the backend on transient 503s.
 const queryClient = new QueryClient({
  defaultOptions: {
    queries: {
-      staleTime: 10_000,
-      retry: 1,
-      refetchOnWindowFocus: true,
+      staleTime: STALE_TIME.REFERENCE,    // 5 min — see api/queryConstants.ts
+      gcTime:    GC_TIME.STANDARD,        // 5 min — explicit; was TanStack-default
+      retry:     1,
+      refetchOnWindowFocus: false,        // per-query opt-in for live-tile queries
    },
  },
 });

+// Phase 4 helper: wrap a lazy route in a page-shaped Suspense fallback.
+// The same Skeleton variant lands on every route so the transition is
+// visually consistent — operators learn "skeleton bars = chunk loading"
+// once and never see a different placeholder elsewhere.
+function lazyRoute(element: React.ReactNode) {
+  return <Suspense fallback={<Skeleton variant="page" />}>{element}</Suspense>;
+}
+
 createRoot(document.getElementById('root')!).render(
  <StrictMode>
    <ErrorBoundary>
      <QueryClientProvider client={queryClient}>
+        <Toaster />
        <AuthProvider>
          <AuthGate>
            <BrowserRouter>
+              <CommandPaletteHost />
              <Routes>
                <Route element={<Layout />}>
+                  {/* Dashboard stays eager — landing route for every cold load. */}
                  <Route index element={<DashboardPage />} />
-                  <Route path="certificates" element={<CertificatesPage />} />
-                  <Route path="certificates/:id" element={<CertificateDetailPage />} />
-                  <Route path="agents" element={<AgentsPage />} />
-                  <Route path="agents/:id" element={<AgentDetailPage />} />
-                  <Route path="fleet" element={<AgentFleetPage />} />
-                  <Route path="jobs" element={<JobsPage />} />
-                  <Route path="jobs/:id" element={<JobDetailPage />} />
-                  <Route path="notifications" element={<NotificationsPage />} />
-                  <Route path="policies" element={<PoliciesPage />} />
-                  <Route path="renewal-policies" element={<RenewalPoliciesPage />} />
-                  <Route path="profiles" element={<ProfilesPage />} />
-                  <Route path="issuers" element={<IssuersPage />} />
-                  <Route path="issuers/:id" element={<IssuerDetailPage />} />
+                  <Route path="certificates"            element={lazyRoute(<CertificatesPage />)} />
+                  <Route path="certificates/:id"        element={lazyRoute(<CertificateDetailPage />)} />
+                  <Route path="agents"                  element={lazyRoute(<AgentsPage />)} />
+                  <Route path="agents/:id"              element={lazyRoute(<AgentDetailPage />)} />
+                  <Route path="fleet"                   element={lazyRoute(<AgentFleetPage />)} />
+                  <Route path="jobs"                    element={lazyRoute(<JobsPage />)} />
+                  <Route path="jobs/:id"                element={lazyRoute(<JobDetailPage />)} />
+                  <Route path="notifications"           element={lazyRoute(<NotificationsPage />)} />
+                  <Route path="policies"                element={lazyRoute(<PoliciesPage />)} />
+                  <Route path="renewal-policies"        element={lazyRoute(<RenewalPoliciesPage />)} />
+                  <Route path="profiles"                element={lazyRoute(<ProfilesPage />)} />
+                  <Route path="issuers"                 element={lazyRoute(<IssuersPage />)} />
+                  <Route path="issuers/:id"             element={lazyRoute(<IssuerDetailPage />)} />
                  {/* Rank 8 — operator-managed multi-level CA hierarchy.
                      Admin-gated at the API; the page renders the
                      backend's 403 as ErrorState for non-admin
                      callers. See docs/intermediate-ca-hierarchy.md. */}
-                  <Route path="issuers/:id/hierarchy" element={<IssuerHierarchyPage />} />
-                  <Route path="targets" element={<TargetsPage />} />
-                  <Route path="targets/:id" element={<TargetDetailPage />} />
-                  <Route path="owners" element={<OwnersPage />} />
-                  <Route path="teams" element={<TeamsPage />} />
-                  <Route path="agent-groups" element={<AgentGroupsPage />} />
-                  <Route path="audit" element={<AuditPage />} />
-                  <Route path="short-lived" element={<ShortLivedPage />} />
-                  <Route path="discovery" element={<DiscoveryPage />} />
-                  <Route path="network-scans" element={<NetworkScanPage />} />
-                  <Route path="health-monitor" element={<HealthMonitorPage />} />
-                  <Route path="digest" element={<DigestPage />} />
-                  <Route path="observability" element={<ObservabilityPage />} />
+                  <Route path="issuers/:id/hierarchy"   element={lazyRoute(<IssuerHierarchyPage />)} />
+                  <Route path="targets"                 element={lazyRoute(<TargetsPage />)} />
+                  <Route path="targets/:id"             element={lazyRoute(<TargetDetailPage />)} />
+                  <Route path="owners"                  element={lazyRoute(<OwnersPage />)} />
+                  <Route path="teams"                   element={lazyRoute(<TeamsPage />)} />
+                  <Route path="agent-groups"            element={lazyRoute(<AgentGroupsPage />)} />
+                  <Route path="audit"                   element={lazyRoute(<AuditPage />)} />
+                  <Route path="short-lived"             element={lazyRoute(<ShortLivedPage />)} />
+                  <Route path="discovery"               element={lazyRoute(<DiscoveryPage />)} />
+                  <Route path="network-scans"           element={lazyRoute(<NetworkScanPage />)} />
+                  <Route path="health-monitor"          element={lazyRoute(<HealthMonitorPage />)} />
+                  <Route path="digest"                  element={lazyRoute(<DigestPage />)} />
+                  <Route path="observability"           element={lazyRoute(<ObservabilityPage />)} />
                  {/* SCEP RFC 8894 + Intune master bundle Phase 9.4 (initial)
                      + Phase 9 follow-up (rebrand): per-profile SCEP
                      Administration page with Profiles / Intune Monitoring /
@@ -108,17 +186,17 @@ createRoot(document.getElementById('root')!).render(
                      itself renders an "Admin access required" banner for
                      non-admin callers and skips the underlying API calls so
                      the server never sees a 403-prone request. */}
-                  <Route path="scep" element={<SCEPAdminPage />} />
+                  <Route path="scep"                    element={lazyRoute(<SCEPAdminPage />)} />
                  {/* Backward-compat alias for external bookmarks the Phase 9
                      release advertised. Lands on the Intune Monitoring tab. */}
-                  <Route path="scep/intune" element={<SCEPAdminPage />} />
+                  <Route path="scep/intune"             element={lazyRoute(<SCEPAdminPage />)} />
                  {/* EST RFC 7030 hardening master bundle Phase 8: per-profile
                      EST Administration page with Profiles / Recent Activity /
                      Trust Bundle tabs. Same admin-gate pattern as SCEP — the
                      route is unconditional; the page renders an "Admin access
                      required" banner for non-admin callers and skips the
                      underlying API calls so the server never sees a 403. */}
-                  <Route path="est" element={<ESTAdminPage />} />
+                  <Route path="est"                     element={lazyRoute(<ESTAdminPage />)} />
                  {/* Bundle 1 Phase 10 — RBAC management surface.
                      Every page reads /api/v1/auth/me on mount via the
                      useAuthMe hook and gates affordances against the
@@ -126,19 +204,19 @@ createRoot(document.getElementById('root')!).render(
                      enforcement is the load-bearing layer; client-side
                      hide/disable is UX. */}
                  {/* Bundle 2 Phase 8 — OIDC + session management surface. */}
-                  <Route path="auth/oidc/providers" element={<OIDCProvidersPage />} />
-                  <Route path="auth/oidc/providers/:id" element={<OIDCProviderDetailPage />} />
-                  <Route path="auth/oidc/providers/:id/mappings" element={<GroupMappingsPage />} />
-                  <Route path="auth/sessions" element={<SessionsPage />} />
-                  <Route path="auth/roles" element={<RolesPage />} />
-                  <Route path="auth/roles/:id" element={<RoleDetailPage />} />
-                  <Route path="auth/keys" element={<KeysPage />} />
-                  <Route path="auth/settings" element={<AuthSettingsPage />} />
-                  <Route path="auth/approvals" element={<ApprovalsPage />} />
+                  <Route path="auth/oidc/providers"               element={lazyRoute(<OIDCProvidersPage />)} />
+                  <Route path="auth/oidc/providers/:id"           element={lazyRoute(<OIDCProviderDetailPage />)} />
+                  <Route path="auth/oidc/providers/:id/mappings"  element={lazyRoute(<GroupMappingsPage />)} />
+                  <Route path="auth/sessions"                     element={lazyRoute(<SessionsPage />)} />
+                  <Route path="auth/roles"                        element={lazyRoute(<RolesPage />)} />
+                  <Route path="auth/roles/:id"                    element={lazyRoute(<RoleDetailPage />)} />
+                  <Route path="auth/keys"                         element={lazyRoute(<KeysPage />)} />
+                  <Route path="auth/settings"                     element={lazyRoute(<AuthSettingsPage />)} />
+                  <Route path="auth/approvals"                    element={lazyRoute(<ApprovalsPage />)} />
                  {/* Audit 2026-05-10 CRIT-4 closure — break-glass admin surface. */}
-                  <Route path="auth/breakglass" element={<BreakglassPage />} />
+                  <Route path="auth/breakglass"                   element={lazyRoute(<BreakglassPage />)} />
                  {/* Audit 2026-05-10 MED-11 closure — federated-user admin. */}
-                  <Route path="auth/users" element={<UsersPage />} />
+                  <Route path="auth/users"                        element={lazyRoute(<UsersPage />)} />
                </Route>
              </Routes>
            </BrowserRouter>
@@ -1,5 +1,6 @@
 import { useEffect, useState } from 'react';
 import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { toast } from 'sonner';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
 import { getAgentGroups, deleteAgentGroup, createAgentGroup, updateAgentGroup } from '../api/client';
 import PageHeader from '../components/PageHeader';
@@ -7,6 +8,7 @@ import DataTable from '../components/DataTable';
 import type { Column } from '../components/DataTable';
 import StatusBadge from '../components/StatusBadge';
 import ErrorState from '../components/ErrorState';
+import ConfirmDialog from '../components/ConfirmDialog';
 import { formatDateTime } from '../api/utils';
 import type { AgentGroup } from '../api/types';

@@ -254,6 +256,7 @@ export default function AgentGroupsPage() {
  const queryClient = useQueryClient();
  const [showCreate, setShowCreate] = useState(false);
  const [editingGroup, setEditingGroup] = useState<AgentGroup | null>(null);
+  const [confirmDelete, setConfirmDelete] = useState<AgentGroup | null>(null);

  const { data, isLoading, error, refetch } = useQuery({
    queryKey: ['agent-groups'],
@@ -263,6 +266,8 @@ export default function AgentGroupsPage() {
  const deleteMutation = useTrackedMutation({
    mutationFn: deleteAgentGroup,
    invalidates: [['agent-groups']],
+    onSuccess: () => toast.success('Agent group deleted'),
+    onError: (err: Error) => toast.error(`Delete failed: ${err.message}`),
  });

  const createMutation = useTrackedMutation({
@@ -337,7 +342,7 @@ export default function AgentGroupsPage() {
            Edit
          </button>
          <button
-            onClick={(e) => { e.stopPropagation(); if (confirm(`Delete group ${g.name}?`)) deleteMutation.mutate(g.id); }}
+            onClick={(e) => { e.stopPropagation(); setConfirmDelete(g); }}
            className="text-xs text-red-600 hover:text-red-700 transition-colors"
          >
            Delete
@@ -385,6 +390,22 @@ export default function AgentGroupsPage() {
        isLoading={updateMutation.isPending}
        error={updateMutation.error ? (updateMutation.error as Error).message : null}
      />
+      <ConfirmDialog
+        open={confirmDelete !== null}
+        title="Delete agent group"
+        message={
+          confirmDelete
+            ? `Delete group ${confirmDelete.name}? This will remove the group definition; agents currently in the group will fall back to default assignment.`
+            : ''
+        }
+        confirmLabel="Delete"
+        destructive
+        onConfirm={() => {
+          if (confirmDelete) deleteMutation.mutate(confirmDelete.id);
+          setConfirmDelete(null);
+        }}
+        onCancel={() => setConfirmDelete(null)}
+      />
    </>
  );
 }
@@ -9,6 +9,7 @@ import {
  BlockedByDependenciesError,
 } from '../api/client';
 import PageHeader from '../components/PageHeader';
+import ModalDialog from '../components/ModalDialog';
 import DataTable from '../components/DataTable';
 import type { Column } from '../components/DataTable';
 import StatusBadge from '../components/StatusBadge';
@@ -309,129 +310,133 @@ function RetireModal({
 }) {
  if (mode.kind === 'closed') return null;

+  // Phase 5 closure (FE-H3): swapped inline `<div role="dialog">` markup
+  // for ModalDialog (Headless UI). Each of the 3 modes (confirm / blocked /
+  // error) renders inside the same dialog shell, so focus trap + ESC + click-
+  // outside come for free. Title + footer change per mode; body is the
+  // mode-specific content.
+  const title =
+    mode.kind === 'confirm' ? 'Retire agent' :
+    mode.kind === 'blocked' ? 'Cannot retire — active dependencies' :
+    /* error */ 'Retire failed';
+
  return (
-    <div
-      role="dialog"
-      aria-modal="true"
-      className="fixed inset-0 z-40 flex items-center justify-center bg-black/40"
-      onClick={onClose}
+    <ModalDialog
+      open={true}
+      title={title}
+      onClose={pending ? () => {} : onClose}
+      maxWidth="lg"
+      footer={
+        mode.kind === 'confirm' ? (
+          <>
+            <button
+              type="button"
+              onClick={onClose}
+              className="px-4 py-2 text-sm text-ink-muted hover:text-ink"
+              disabled={pending}
+            >
+              Cancel
+            </button>
+            <button
+              type="button"
+              onClick={onSoftRetire}
+              disabled={pending}
+              className="px-4 py-2 text-sm font-medium text-white bg-danger rounded hover:bg-danger/90 disabled:opacity-50"
+            >
+              {pending ? 'Retiring…' : 'Retire'}
+            </button>
+          </>
+        ) : mode.kind === 'blocked' ? (
+          <>
+            <button
+              type="button"
+              onClick={onClose}
+              className="px-4 py-2 text-sm text-ink-muted hover:text-ink"
+              disabled={pending}
+            >
+              Cancel
+            </button>
+            <button
+              type="button"
+              onClick={onForceRetire}
+              // Backend enforces reason on force; keep the GUI in lockstep
+              // rather than letting a 400 bounce back.
+              disabled={pending || !mode.reason.trim()}
+              className="px-4 py-2 text-sm font-medium text-white bg-danger rounded hover:bg-danger/90 disabled:opacity-50"
+            >
+              {pending ? 'Force-retiring…' : 'Force retire'}
+            </button>
+          </>
+        ) : (
+          <button
+            type="button"
+            onClick={onClose}
+            className="px-4 py-2 text-sm text-ink-muted hover:text-ink"
+          >
+            Close
+          </button>
+        )
+      }
    >
-      <div
-        className="w-full max-w-lg rounded-lg bg-surface p-6 shadow-lg border border-border"
-        onClick={(e) => e.stopPropagation()}
-      >
-        {mode.kind === 'confirm' && (
-          <>
-            <h2 className="text-lg font-semibold text-ink">Retire agent</h2>
-            <p className="mt-2 text-sm text-ink-muted">
-              <span className="font-mono">{mode.agent.name}</span> ({mode.agent.id}) will be
-              soft-retired. The agent will stop receiving heartbeats and be removed from active
-              listings. This is reversible only by direct database intervention.
-            </p>
-            <label className="mt-4 block text-xs font-medium text-ink-muted">
-              Reason (optional)
-              <input
-                type="text"
-                value={mode.reason}
-                onChange={(e) => onReasonChange(e.target.value)}
-                placeholder="e.g. decommissioning rack 7"
-                className="mt-1 w-full rounded border border-border bg-surface-alt px-2 py-1 text-sm"
-              />
-            </label>
-            <div className="mt-6 flex justify-end gap-2">
-              <button
-                type="button"
-                onClick={onClose}
-                className="px-4 py-2 text-sm text-ink-muted hover:text-ink"
-                disabled={pending}
-              >
-                Cancel
-              </button>
-              <button
-                type="button"
-                onClick={onSoftRetire}
-                disabled={pending}
-                className="px-4 py-2 text-sm font-medium text-white bg-danger rounded hover:bg-danger/90 disabled:opacity-50"
-              >
-                {pending ? 'Retiring…' : 'Retire'}
-              </button>
-            </div>
-          </>
-        )}
+      {mode.kind === 'confirm' && (
+        <>
+          <p className="text-sm text-ink-muted">
+            <span className="font-mono">{mode.agent.name}</span> ({mode.agent.id}) will be
+            soft-retired. The agent will stop receiving heartbeats and be removed from active
+            listings. This is reversible only by direct database intervention.
+          </p>
+          <label className="mt-4 block text-xs font-medium text-ink-muted">
+            Reason (optional)
+            <input
+              type="text"
+              value={mode.reason}
+              onChange={(e) => onReasonChange(e.target.value)}
+              placeholder="e.g. decommissioning rack 7"
+              className="mt-1 w-full rounded border border-border bg-surface-alt px-2 py-1 text-sm"
+            />
+          </label>
+        </>
+      )}

-        {mode.kind === 'blocked' && (
-          <>
-            <h2 className="text-lg font-semibold text-ink">Cannot retire — active dependencies</h2>
-            <p className="mt-2 text-sm text-ink-muted">
-              The agent <span className="font-mono">{mode.agent.name}</span> still has downstream
-              work tied to it. Force-retiring will cascade-retire all active targets and fail any
-              pending jobs.
-            </p>
-            <dl className="mt-4 grid grid-cols-3 gap-3 text-center">
-              <div className="rounded border border-border bg-surface-alt p-3">
-                <dt className="text-xs text-ink-muted">Active targets</dt>
-                <dd className="mt-1 text-xl font-semibold text-ink">{mode.counts.active_targets}</dd>
-              </div>
-              <div className="rounded border border-border bg-surface-alt p-3">
-                <dt className="text-xs text-ink-muted">Active certs</dt>
-                <dd className="mt-1 text-xl font-semibold text-ink">
-                  {mode.counts.active_certificates}
-                </dd>
-              </div>
-              <div className="rounded border border-border bg-surface-alt p-3">
-                <dt className="text-xs text-ink-muted">Pending jobs</dt>
-                <dd className="mt-1 text-xl font-semibold text-ink">{mode.counts.pending_jobs}</dd>
-              </div>
-            </dl>
-            <label className="mt-4 block text-xs font-medium text-ink-muted">
-              Reason <span className="text-danger">(required for force retire)</span>
-              <input
-                type="text"
-                value={mode.reason}
-                onChange={(e) => onReasonChange(e.target.value)}
-                placeholder="e.g. rack 7 decommission, cascade retire"
-                className="mt-1 w-full rounded border border-border bg-surface-alt px-2 py-1 text-sm"
-              />
-            </label>
-            <div className="mt-6 flex justify-end gap-2">
-              <button
-                type="button"
-                onClick={onClose}
-                className="px-4 py-2 text-sm text-ink-muted hover:text-ink"
-                disabled={pending}
-              >
-                Cancel
-              </button>
-              <button
-                type="button"
-                onClick={onForceRetire}
-                // Backend enforces reason on force; keep the GUI in lockstep
-                // rather than letting a 400 bounce back.
-                disabled={pending || !mode.reason.trim()}
-                className="px-4 py-2 text-sm font-medium text-white bg-danger rounded hover:bg-danger/90 disabled:opacity-50"
-              >
-                {pending ? 'Force-retiring…' : 'Force retire'}
-              </button>
+      {mode.kind === 'blocked' && (
+        <>
+          <p className="text-sm text-ink-muted">
+            The agent <span className="font-mono">{mode.agent.name}</span> still has downstream
+            work tied to it. Force-retiring will cascade-retire all active targets and fail any
+            pending jobs.
+          </p>
+          <dl className="mt-4 grid grid-cols-3 gap-3 text-center">
+            <div className="rounded border border-border bg-surface-alt p-3">
+              <dt className="text-xs text-ink-muted">Active targets</dt>
+              <dd className="mt-1 text-xl font-semibold text-ink">{mode.counts.active_targets}</dd>
            </div>
-          </>
-        )}
+            <div className="rounded border border-border bg-surface-alt p-3">
+              <dt className="text-xs text-ink-muted">Active certs</dt>
+              <dd className="mt-1 text-xl font-semibold text-ink">
+                {mode.counts.active_certificates}
+              </dd>
+            </div>
+            <div className="rounded border border-border bg-surface-alt p-3">
+              <dt className="text-xs text-ink-muted">Pending jobs</dt>
+              <dd className="mt-1 text-xl font-semibold text-ink">{mode.counts.pending_jobs}</dd>
+            </div>
+          </dl>
+          <label className="mt-4 block text-xs font-medium text-ink-muted">
+            Reason <span className="text-danger">(required for force retire)</span>
+            <input
+              type="text"
+              value={mode.reason}
+              onChange={(e) => onReasonChange(e.target.value)}
+              placeholder="e.g. rack 7 decommission, cascade retire"
+              className="mt-1 w-full rounded border border-border bg-surface-alt px-2 py-1 text-sm"
+            />
+          </label>
+        </>
+      )}

-        {mode.kind === 'error' && (
-          <>
-            <h2 className="text-lg font-semibold text-ink">Retire failed</h2>
-            <p className="mt-2 text-sm text-danger">{mode.message}</p>
-            <div className="mt-6 flex justify-end">
-              <button
-                type="button"
-                onClick={onClose}
-                className="px-4 py-2 text-sm text-ink-muted hover:text-ink"
-              >
-                Close
-              </button>
-            </div>
-          </>
-        )}
-      </div>
-    </div>
+      {mode.kind === 'error' && (
+        <p className="text-sm text-danger">{mode.message}</p>
+      )}
+    </ModalDialog>
  );
 }
@@ -1,12 +1,14 @@
 import { useState } from 'react';
 import { useParams, useNavigate } from 'react-router-dom';
-import { useQuery } from '@tanstack/react-query';
+import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { toast } from 'sonner';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
 import { getCertificate, getCertificateVersions, triggerRenewal, triggerDeployment, archiveCertificate, revokeCertificate, updateCertificate, getTargets, getJobs, getRenewalPolicies, getProfiles, getProfile, downloadCertificatePEM, exportCertificatePKCS12, getOCSPStatus, fetchCRL, getAdminCRLCache } from '../api/client';
 import { REVOCATION_REASONS } from '../api/types';
 import PageHeader from '../components/PageHeader';
 import StatusBadge from '../components/StatusBadge';
 import ErrorState from '../components/ErrorState';
+import ConfirmDialog from '../components/ConfirmDialog';
 import { useAuth } from '../components/AuthProvider';
 import { formatDate, formatDateTime, daysUntil, expiryColor, timeAgo } from '../api/utils';
 import type { Job, CRLCacheRow } from '../api/types';
@@ -415,6 +417,7 @@ function InlinePolicyEditor({ certId, currentPolicyId, currentProfileId }: { cer
 export default function CertificateDetailPage() {
  const { id } = useParams<{ id: string }>();
  const navigate = useNavigate();
+  const queryClient = useQueryClient();
  const [showDeploy, setShowDeploy] = useState(false);
  const [deployTargetId, setDeployTargetId] = useState('');
  const [showRevoke, setShowRevoke] = useState(false);
@@ -422,6 +425,7 @@ export default function CertificateDetailPage() {
  const [showExport, setShowExport] = useState(false);
  const [pkcs12Password, setPkcs12Password] = useState('');
  const [exporting, setExporting] = useState(false);
+  const [confirmArchive, setConfirmArchive] = useState(false);

  const { data: cert, isLoading, error, refetch } = useQuery({
    queryKey: ['certificate', id],
@@ -462,10 +466,30 @@ export default function CertificateDetailPage() {
    },
  });

-  const archiveMutation = useTrackedMutation({
+  // Phase 2 TQ-M3 closure: optimistic archive. Flip the cert's status
+  // to 'Archived' in the ['certificate', id] cache snapshot
+  // immediately; on success navigate (the user leaves the page so the
+  // optimistic data doesn't linger). On error, restore the snapshot
+  // + surface the error toast — the user stays on the page with
+  // status reverted.
+  type ArchiveSnapshot = { prev?: { status?: string } | undefined };
+  const archiveMutation = useTrackedMutation<unknown, Error, void, ArchiveSnapshot>({
    mutationFn: () => archiveCertificate(id!),
    invalidates: [['certificates']],
+    onMutate: async (): Promise<ArchiveSnapshot> => {
+      await queryClient.cancelQueries({ queryKey: ['certificate', id] });
+      const prev = queryClient.getQueryData(['certificate', id]) as ArchiveSnapshot['prev'];
+      if (prev) {
+        queryClient.setQueryData(['certificate', id], { ...prev, status: 'Archived' });
+      }
+      return { prev };
+    },
+    onError: (err, _vars, snap) => {
+      if (snap?.prev) queryClient.setQueryData(['certificate', id], snap.prev);
+      toast.error(`Archive failed: ${err.message}`);
+    },
    onSuccess: () => {
+      toast.success('Certificate archived');
      navigate('/certificates');
    },
  });
@@ -490,7 +514,7 @@ export default function CertificateDetailPage() {
      a.click();
      URL.revokeObjectURL(url);
    } catch (err) {
-      alert(`Export failed: ${err instanceof Error ? err.message : err}`);
+      toast.error(`Export failed: ${err instanceof Error ? err.message : err}`);
    } finally {
      setExporting(false);
    }
@@ -509,7 +533,7 @@ export default function CertificateDetailPage() {
      setShowExport(false);
      setPkcs12Password('');
    } catch (err) {
-      alert(`Export failed: ${err instanceof Error ? err.message : err}`);
+      toast.error(`Export failed: ${err instanceof Error ? err.message : err}`);
    } finally {
      setExporting(false);
    }
@@ -600,7 +624,7 @@ export default function CertificateDetailPage() {
            )}
            {!isArchived && (
              <button
-                onClick={() => { if (confirm('Archive this certificate? This cannot be undone.')) archiveMutation.mutate(); }}
+                onClick={() => setConfirmArchive(true)}
                disabled={archiveMutation.isPending}
                className="btn btn-ghost text-xs text-red-400 hover:text-red-300 disabled:opacity-50"
              >
@@ -931,6 +955,23 @@ export default function CertificateDetailPage() {
          </div>
        </div>
      )}
+      {/* UX-H2 / UX-H3 closure — archive is the most-irreversible
+          single-cert action. Gate behind a typed-confirmation prompt
+          so the operator cannot fat-finger through the dialog. */}
+      <ConfirmDialog
+        open={confirmArchive}
+        title="Archive this certificate"
+        message={`This action cannot be undone. The certificate (${cert?.common_name || id}) will be moved to the archive bucket and removed from the active inventory. Active deployments + renewal policies referencing it will be skipped.`}
+        confirmLabel="Archive"
+        cancelLabel="Cancel"
+        destructive
+        typedConfirmation="archive"
+        onConfirm={() => {
+          archiveMutation.mutate();
+          setConfirmArchive(false);
+        }}
+        onCancel={() => setConfirmArchive(false)}
+      />
    </>
  );
 }
@@ -1,5 +1,7 @@
-import { useState } from 'react';
+import { Fragment, useState } from 'react';
+import { Transition } from '@headlessui/react';
 import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { toast } from 'sonner';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
 import { useListParams } from '../hooks/useListParams';
 import { useNavigate } from 'react-router-dom';
@@ -30,25 +32,35 @@ function CreateCertificateModal({ onClose, onSuccess }: { onClose: () => void; o
  });
  const [error, setError] = useState('');

+  // Phase 2 P-H1 closure: pre-Phase-2 there were 4 duplicate-key pairs
+  // between this modal and the parent CertificatesPage filter bar:
+  //   ['profiles']        vs ['profiles-filter']
+  //   ['issuers']         vs ['issuers-filter']
+  //   ['owners', 'form']  vs ['owners-filter']
+  //   ['teams', 'form']   vs ['teams-filter']
+  // TanStack v5 dedupes on serialized queryKey, so the same call shape
+  // shared between modal + filter now hits the cache exactly once.
+  // Both sites now request per_page=100 (was 500/none here, 100 there
+  // — the modal's "500 entries" was over-fetching for a dropdown).
  const { data: profilesResp } = useQuery({
-    queryKey: ['profiles'],
-    queryFn: () => getProfiles(),
+    queryKey: ['profiles', { per_page: 100 }],
+    queryFn: () => getProfiles({ per_page: '100' }),
  });
  const { data: issuersResp } = useQuery({
-    queryKey: ['issuers'],
-    queryFn: () => getIssuers(),
+    queryKey: ['issuers', { per_page: 100 }],
+    queryFn: () => getIssuers({ per_page: '100' }),
  });
  // C-001: owner_id, team_id, and renewal_policy_id are required by the
  // server (handler in internal/api/handler/certificates.go) and by OpenAPI.
  // Load the catalog so the user selects valid FKs instead of typing free-text
  // IDs that would 400 at the server.
  const { data: ownersResp } = useQuery({
-    queryKey: ['owners', 'form'],
-    queryFn: () => getOwners({ per_page: '500' }),
+    queryKey: ['owners', { per_page: 100 }],
+    queryFn: () => getOwners({ per_page: '100' }),
  });
  const { data: teamsResp } = useQuery({
-    queryKey: ['teams', 'form'],
-    queryFn: () => getTeams({ per_page: '500' }),
+    queryKey: ['teams', { per_page: 100 }],
+    queryFn: () => getTeams({ per_page: '100' }),
  });
  // G-1: swap from getPolicies (compliance rules, pol-*) to getRenewalPolicies
  // (lifecycle policies, rp-*). managed_certificates.renewal_policy_id FK
@@ -467,11 +479,28 @@ export default function CertificatesPage() {
  const [showBulkReassign, setShowBulkReassign] = useState(false);
  const [bulkRenewProgress, setBulkRenewProgress] = useState<{ done: number; total: number; running: boolean } | null>(null);

-  const { data: issuersData } = useQuery({ queryKey: ['issuers-filter'], queryFn: () => getIssuers({ per_page: '100' }) });
-  const { data: ownersData } = useQuery({ queryKey: ['owners-filter'], queryFn: () => getOwners({ per_page: '100' }) });
-  const { data: profilesData } = useQuery({ queryKey: ['profiles-filter'], queryFn: () => getProfiles({ per_page: '100' }) });
+  // Phase 2 P-H1 closure: queryKey now matches CreateCertificateModal's
+  // upstream calls byte-for-byte (`[name, { per_page: 100 }]`). TanStack
+  // v5 serializes the key on insert + comparison; identical serialization
+  // means the modal + filter share one cache slot. Pre-Phase-2 these
+  // were 4 independent fetches that returned the same data.
+  const { data: issuersData } = useQuery({
+    queryKey: ['issuers', { per_page: 100 }],
+    queryFn: () => getIssuers({ per_page: '100' }),
+  });
+  const { data: ownersData } = useQuery({
+    queryKey: ['owners', { per_page: 100 }],
+    queryFn: () => getOwners({ per_page: '100' }),
+  });
+  const { data: profilesData } = useQuery({
+    queryKey: ['profiles', { per_page: 100 }],
+    queryFn: () => getProfiles({ per_page: '100' }),
+  });
  // F-1 closure: hydrate the team filter dropdown.
-  const { data: teamsFilterData } = useQuery({ queryKey: ['teams-filter'], queryFn: () => getTeams({ per_page: '100' }) });
+  const { data: teamsFilterData } = useQuery({
+    queryKey: ['teams', { per_page: 100 }],
+    queryFn: () => getTeams({ per_page: '100' }),
+  });

  const params: Record<string, string> = {};
  if (statusFilter)  params.status         = statusFilter;
@@ -511,9 +540,29 @@ export default function CertificatesPage() {
        total: result.total_matched,
        running: false,
      });
-    } catch {
+      // UX-L5 closure (Phase 1): post-action toast with a "View jobs"
+      // action that deep-links to the Jobs page filtered to the
+      // certificate IDs we just renewed. The audit's missing
+      // "what just happened" affordance — operators can now jump
+      // straight to the resulting jobs.
+      if (result.total_enqueued > 0) {
+        toast.success(
+          `Triggered renewal for ${result.total_enqueued} certificate${result.total_enqueued > 1 ? 's' : ''}`,
+          {
+            action: {
+              label: `View ${result.total_enqueued} jobs`,
+              onClick: () =>
+                navigate(`/jobs?certificate_ids=${ids.join(',')}`),
+            },
+            duration: 8000,
+          },
+        );
+      }
+    } catch (err) {
      // surface as a "0 of N" terminal state — no retries.
      setBulkRenewProgress({ done: 0, total: ids.length, running: false });
+      const msg = err instanceof Error ? err.message : String(err);
+      toast.error(`Bulk renewal failed: ${msg}`);
    }
    queryClient.invalidateQueries({ queryKey: ['certificates'] });
    setSelectedIds(new Set());
@@ -566,8 +615,20 @@ export default function CertificatesPage() {
        }
      />

-      {/* Bulk Action Bar */}
-      {hasSelection && (
+      {/* Bulk Action Bar — UX-L5 (Phase 1): Headless UI <Transition>
+          wraps the slide-in/out so the bar doesn't snap when selection
+          flips. Transition respects prefers-reduced-motion via the
+          global @media block in index.css. */}
+      <Transition
+        show={hasSelection}
+        as={Fragment}
+        enter="transition-all duration-200 ease-out"
+        enterFrom="opacity-0 -translate-y-2"
+        enterTo="opacity-100 translate-y-0"
+        leave="transition-all duration-150 ease-in"
+        leaveFrom="opacity-100 translate-y-0"
+        leaveTo="opacity-0 -translate-y-2"
+      >
        <div className="px-6 py-3 bg-brand-50 border-b border-brand-200 flex items-center justify-between">
          <span className="text-sm text-brand-600 font-medium">{selectedArray.length} selected</span>
          <div className="flex gap-2">
@@ -593,7 +654,7 @@ export default function CertificatesPage() {
            </button>
          </div>
        </div>
-      )}
+      </Transition>

      {/* Bulk Renewal Success */}
      {bulkRenewProgress && !bulkRenewProgress.running && (
@@ -1,11 +1,8 @@
-import { useState } from 'react';
-import { useQuery } from '@tanstack/react-query';
+import { Suspense, lazy, useEffect, useMemo, useState } from 'react';
+import { useQuery, useQueryClient } from '@tanstack/react-query';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
+import { STALE_TIME } from '../api/queryConstants';
 import { useNavigate, useSearchParams } from 'react-router-dom';
-import {
-  BarChart, Bar, LineChart, Line, PieChart, Pie, Cell,
-  XAxis, YAxis, CartesianGrid, Tooltip, ResponsiveContainer, Legend,
-} from 'recharts';
 import {
  getCertificates, getJobs, getHealth,
  getDashboardSummary, getCertificatesByStatus, getExpirationTimeline,
@@ -13,11 +10,28 @@ import {
 } from '../api/client';
 import PageHeader from '../components/PageHeader';
 import StatusBadge from '../components/StatusBadge';
+import Skeleton from '../components/Skeleton';
 import { daysUntil, expiryColor, formatDate } from '../api/utils';
-import OnboardingWizard from './OnboardingWizard';
+// Phase 4 closure (PERF-M1 + P-H3): memo-wrapped chart panels so a query
+// refetch in one tile doesn't force every Recharts subtree to reconcile.
+// See pages/dashboard/charts.tsx for the equality model.
+import {
+  CertsByStatusPieChart,
+  ExpirationTimelineBarChart,
+  JobTrendsLineChart,
+  IssuanceRateBarChart,
+  type PieDatum,
+  type WeeklyExpirationDatum,
+} from './dashboard/charts';
+// Phase 4 closure (FE-M5): OnboardingWizard is 1043 LOC + only renders
+// on first-run dashboards (one-time dismiss persisted to localStorage).
+// Lazy-loading the wizard keeps its step-form code off the hot path for
+// every dashboard load after the operator dismisses it once.
+const OnboardingWizard = lazy(() => import('./OnboardingWizard'));

-// Convert PascalCase status like "RenewalInProgress" to "Renewal In Progress"
-const formatStatus = (s: string) => s.replace(/([a-z])([A-Z])/g, '$1 $2');
+// formatStatus moved to pages/dashboard/charts.tsx in Phase 4 alongside
+// the memoized chart panels that use it; deleted from here in Hotfix #8
+// to close CodeQL js/unused-local-variable alert #35.

 const STATUS_COLORS: Record<string, string> = {
  Active: '#10b981',
@@ -53,30 +67,9 @@ function StatCard({ label, value, icon, color }: { label: string; value: string
  );
 }

-function ChartCard({ title, children }: { title: string; children: React.ReactNode }) {
-  return (
-    <div className="bg-surface border border-surface-border rounded p-5 shadow-sm">
-      <h3 className="text-sm font-semibold text-ink-muted mb-4">{title}</h3>
-      <div className="h-64">
-        {children}
-      </div>
-    </div>
-  );
-}
-
-const CustomTooltip = ({ active, payload, label }: any) => {
-  if (!active || !payload?.length) return null;
-  return (
-    <div className="bg-surface border border-surface-border rounded px-3 py-2 text-xs shadow-lg">
-      <p className="text-ink mb-1">{label}</p>
-      {payload.map((entry: any, i: number) => (
-        <p key={i} style={{ color: entry.color }}>
-          {entry.name}: {typeof entry.value === 'number' && entry.name?.includes('rate') ? `${entry.value.toFixed(1)}%` : entry.value}
-        </p>
-      ))}
-    </div>
-  );
-};
+// ChartCard + CustomTooltip + formatShortDate moved to
+// pages/dashboard/charts.tsx (Phase 4 PERF-M1 closure) where they live
+// alongside the memo-wrapped chart panels that consume them.

 function DigestCard() {
  const [previewHtml, setPreviewHtml] = useState<string | null>(null);
@@ -182,16 +175,117 @@ export default function DashboardPage() {
  // even after dismissal. Takes precedence over localStorage dismissal; stripped on close.
  const forceOnboarding = searchParams.get('onboarding') === '1';

+  // Phase 2 PERF-H1 closure: visibility-aware polling.
+  // Pre-Phase-2: Dashboard fired 9 useQuery on mount with 8 polling
+  // (1× 10s + 5× 30s + 2× 60s = ~18 background calls/min). When the
+  // browser tab is hidden (operator working in a different tab) the
+  // polling still fires — wasted backend cycles + battery.
+  //
+  // Fix: track document.visibilityState; when hidden, the
+  // refetchInterval gate below returns false (paused). Also bump the
+  // `jobs` poll from 10s → 30s — the live-tile reason (operator
+  // watching a job finish) doesn't need 10s granularity when 30s is
+  // already inside the human-attention window. The CertificateDetail
+  // page is where 10s polling makes sense (the operator is staring
+  // at the specific job they just kicked off).
+  //
+  // Backend-aggregation gap: ['dashboard-summary'] + ['certs-by-status']
+  // + ['certificates', {}] could collapse into a single endpoint
+  // (3 round-trips → 1) — tracked as a separate Phase-3 backend item.
+  const queryClient = useQueryClient();
+  const [tabVisible, setTabVisible] = useState(
+    typeof document !== 'undefined' ? document.visibilityState === 'visible' : true,
+  );
+  useEffect(() => {
+    if (typeof document === 'undefined') return;
+    const handler = () => {
+      const visible = document.visibilityState === 'visible';
+      setTabVisible(visible);
+      // When the tab becomes visible after being hidden, immediately
+      // invalidate the dashboard live-tile queries so the operator
+      // sees fresh data instead of waiting for the next poll tick.
+      if (visible) {
+        queryClient.invalidateQueries({ queryKey: ['health'] });
+        queryClient.invalidateQueries({ queryKey: ['dashboard-summary'] });
+        queryClient.invalidateQueries({ queryKey: ['jobs', {}] });
+        queryClient.invalidateQueries({ queryKey: ['certs-by-status'] });
+      }
+    };
+    document.addEventListener('visibilitychange', handler);
+    return () => document.removeEventListener('visibilitychange', handler);
+  }, [queryClient]);
+
+  // refetchInterval returns false (paused) when the tab is hidden;
+  // otherwise the per-query base interval applies.
+  const liveTileGate = (baseMs: number) => (tabVisible ? baseMs : false);
+
  // All hooks must be called unconditionally (React rules of hooks — no hooks after early returns)
-  const { data: health } = useQuery({ queryKey: ['health'], queryFn: getHealth, refetchInterval: 30000 });
-  const { data: summary } = useQuery({ queryKey: ['dashboard-summary'], queryFn: getDashboardSummary, refetchInterval: 30000 });
+  const { data: health } = useQuery({
+    queryKey: ['health'], queryFn: getHealth,
+    refetchInterval: liveTileGate(30_000),
+    refetchOnWindowFocus: true, staleTime: STALE_TIME.REAL_TIME,
+  });
+  const { data: summary } = useQuery({
+    queryKey: ['dashboard-summary'], queryFn: getDashboardSummary,
+    refetchInterval: liveTileGate(30_000),
+    refetchOnWindowFocus: true, staleTime: STALE_TIME.REAL_TIME,
+  });
  const { data: issuersData } = useQuery({ queryKey: ['issuers'], queryFn: () => getIssuers() });
-  const { data: statusCounts } = useQuery({ queryKey: ['certs-by-status'], queryFn: getCertificatesByStatus, refetchInterval: 30000 });
-  const { data: expirationTimeline } = useQuery({ queryKey: ['expiration-timeline'], queryFn: () => getExpirationTimeline(90), refetchInterval: 60000 });
-  const { data: jobTrends } = useQuery({ queryKey: ['job-trends'], queryFn: () => getJobTrends(30), refetchInterval: 30000 });
-  const { data: issuanceRate } = useQuery({ queryKey: ['issuance-rate'], queryFn: () => getIssuanceRate(30), refetchInterval: 60000 });
-  const { data: certs } = useQuery({ queryKey: ['certificates', {}], queryFn: () => getCertificates(), refetchInterval: 30000 });
-  const { data: jobs } = useQuery({ queryKey: ['jobs', {}], queryFn: () => getJobs(), refetchInterval: 10000 });
+  const { data: statusCounts } = useQuery({
+    queryKey: ['certs-by-status'], queryFn: getCertificatesByStatus,
+    refetchInterval: liveTileGate(30_000),
+    refetchOnWindowFocus: true, staleTime: STALE_TIME.REAL_TIME,
+  });
+  const { data: expirationTimeline } = useQuery({
+    queryKey: ['expiration-timeline'], queryFn: () => getExpirationTimeline(90),
+    refetchInterval: liveTileGate(60_000),
+  });
+  const { data: jobTrends } = useQuery({
+    queryKey: ['job-trends'], queryFn: () => getJobTrends(30),
+    refetchInterval: liveTileGate(30_000),
+  });
+  const { data: issuanceRate } = useQuery({
+    queryKey: ['issuance-rate'], queryFn: () => getIssuanceRate(30),
+    refetchInterval: liveTileGate(60_000),
+  });
+  const { data: certs } = useQuery({
+    queryKey: ['certificates', {}], queryFn: () => getCertificates(),
+    refetchInterval: liveTileGate(30_000),
+  });
+  const { data: jobs } = useQuery({
+    queryKey: ['jobs', {}], queryFn: () => getJobs(),
+    refetchInterval: liveTileGate(30_000),     // PERF-H1: 10s → 30s
+    refetchOnWindowFocus: true, staleTime: STALE_TIME.REAL_TIME,
+  });
+
+  // Prepare pie chart data — memoized so the reference is stable across
+  // re-renders that didn't change statusCounts. Without this useMemo the
+  // chart's React.memo prop-equality check fails on every dashboard
+  // re-render (fresh array every time) and the perf win evaporates.
+  //
+  // Hooks must be called unconditionally on every render path (Rules of
+  // Hooks), so these live BEFORE the wizard early-return below — never
+  // after it.
+  const pieData = useMemo<PieDatum[]>(() => (
+    (statusCounts || []).filter(s => s.count > 0).map(s => ({
+      name: s.status,
+      value: s.count,
+      fill: STATUS_COLORS[s.status] || '#64748b',
+    }))
+  ), [statusCounts]);
+
+  // Format expiration heatmap for display — aggregate weekly for 90 days.
+  // Same useMemo reasoning as pieData above.
+  const weeklyExpiration = useMemo<WeeklyExpirationDatum[]>(() => (
+    (expirationTimeline || []).reduce<WeeklyExpirationDatum[]>((acc, bucket, i) => {
+      const weekIdx = Math.floor(i / 7);
+      if (!acc[weekIdx]) {
+        acc[weekIdx] = { week: bucket.date, count: 0 };
+      }
+      acc[weekIdx].count += bucket.count;
+      return acc;
+    }, [])
+  ), [expirationTimeline]);

  // Detect first-run ONCE: no user-configured issuers AND no certificates.
  // Auto-seeded env var issuers (source="env") don't count — they exist on every fresh boot.
@@ -209,17 +303,19 @@ export default function DashboardPage() {

  if ((showWizard && !onboardingDismissed) || forceOnboarding) {
    return (
-      <OnboardingWizard onDismiss={() => {
-        try { localStorage.setItem('certctl:onboarding-dismissed', 'true'); } catch { /* noop */ }
-        setOnboardingDismissed(true);
-        setShowWizard(false);
-        // Strip ?onboarding=1 so page refresh doesn't relaunch the wizard
-        if (searchParams.has('onboarding')) {
-          const next = new URLSearchParams(searchParams);
-          next.delete('onboarding');
-          setSearchParams(next, { replace: true });
-        }
-      }} />
+      <Suspense fallback={<Skeleton variant="page" ariaLabel="Loading onboarding wizard" />}>
+        <OnboardingWizard onDismiss={() => {
+          try { localStorage.setItem('certctl:onboarding-dismissed', 'true'); } catch { /* noop */ }
+          setOnboardingDismissed(true);
+          setShowWizard(false);
+          // Strip ?onboarding=1 so page refresh doesn't relaunch the wizard
+          if (searchParams.has('onboarding')) {
+            const next = new URLSearchParams(searchParams);
+            next.delete('onboarding');
+            setSearchParams(next, { replace: true });
+          }
+        }} />
+      </Suspense>
    );
  }

@@ -229,29 +325,6 @@ export default function DashboardPage() {
  const activeAgents = summary?.active_agents || 0;
  const pendingJobs = summary?.pending_jobs || 0;

-  // Prepare pie chart data
-  const pieData = (statusCounts || []).filter(s => s.count > 0).map(s => ({
-    name: s.status,
-    value: s.count,
-    fill: STATUS_COLORS[s.status] || '#64748b',
-  }));
-
-  // Format expiration heatmap for display — aggregate weekly for 90 days
-  const weeklyExpiration = (expirationTimeline || []).reduce<{ week: string; count: number }[]>((acc, bucket, i) => {
-    const weekIdx = Math.floor(i / 7);
-    if (!acc[weekIdx]) {
-      acc[weekIdx] = { week: bucket.date, count: 0 };
-    }
-    acc[weekIdx].count += bucket.count;
-    return acc;
-  }, []);
-
-  // Format dates for x-axis labels
-  const formatShortDate = (dateStr: string) => {
-    const d = new Date(dateStr + 'T00:00:00');
-    return `${d.getMonth() + 1}/${d.getDate()}`;
-  };
-
  return (
    <>
      <PageHeader
@@ -273,96 +346,19 @@ export default function DashboardPage() {
            icon="M4 4v5h.582m15.356 2A8.001 8.001 0 004.582 9m0 0H9m11 11v-5h-.581m0 0a8.003 8.003 0 01-15.357-2m15.357 2H15" />
        </div>

-        {/* Charts Row 1 */}
+        {/* Charts Row 1 — memo-wrapped panels from pages/dashboard/charts.tsx
+            (Phase 4 PERF-M1). Each panel re-renders only when its own data
+            ref changes, so a refetch on one tile doesn't reconcile the
+            other three Recharts subtrees. */}
        <div className="grid grid-cols-1 lg:grid-cols-2 gap-6">
-          {/* Certificates by Status (Pie) */}
-          <ChartCard title="Certificates by Status">
-            {pieData.length > 0 ? (
-              <ResponsiveContainer width="100%" height="100%">
-                <PieChart>
-                  <Pie
-                    data={pieData}
-                    cx="50%"
-                    cy="50%"
-                    innerRadius={60}
-                    outerRadius={90}
-                    paddingAngle={2}
-                    dataKey="value"
-                    label={({ name, value }) => `${formatStatus(name || '')}: ${value}`}
-                    labelLine={false}
-                  >
-                    {pieData.map((entry, index) => (
-                      <Cell key={index} fill={entry.fill} />
-                    ))}
-                  </Pie>
-                  <Tooltip content={<CustomTooltip />} />
-                  <Legend
-                    verticalAlign="bottom"
-                    height={36}
-                    formatter={(value: string) => <span className="text-xs text-ink-muted">{formatStatus(value)}</span>}
-                  />
-                </PieChart>
-              </ResponsiveContainer>
-            ) : (
-              <div className="h-full flex items-center justify-center text-sm text-ink-faint">No certificate data</div>
-            )}
-          </ChartCard>
-
-          {/* Expiration Heatmap (Bar chart by week) */}
-          <ChartCard title="Expiration Timeline (Next 90 Days)">
-            {weeklyExpiration.length > 0 ? (
-              <ResponsiveContainer width="100%" height="100%">
-                <BarChart data={weeklyExpiration}>
-                  <CartesianGrid strokeDasharray="3 3" stroke="#e2e8f0" />
-                  <XAxis dataKey="week" tick={{ fill: '#64748b', fontSize: 11 }} tickFormatter={formatShortDate} />
-                  <YAxis tick={{ fill: '#64748b', fontSize: 11 }} allowDecimals={false} />
-                  <Tooltip content={<CustomTooltip />} />
-                  <Bar dataKey="count" name="Expiring certs" fill="#f59e0b" radius={[4, 4, 0, 0]} />
-                </BarChart>
-              </ResponsiveContainer>
-            ) : (
-              <div className="h-full flex items-center justify-center text-sm text-ink-faint">No expiration data</div>
-            )}
-          </ChartCard>
+          <CertsByStatusPieChart data={pieData} />
+          <ExpirationTimelineBarChart data={weeklyExpiration} />
        </div>

        {/* Charts Row 2 */}
        <div className="grid grid-cols-1 lg:grid-cols-2 gap-6">
-          {/* Job Trends (Line chart) */}
-          <ChartCard title="Job Success/Failure Trends (30 Days)">
-            {(jobTrends || []).length > 0 ? (
-              <ResponsiveContainer width="100%" height="100%">
-                <LineChart data={jobTrends}>
-                  <CartesianGrid strokeDasharray="3 3" stroke="#e2e8f0" />
-                  <XAxis dataKey="date" tick={{ fill: '#64748b', fontSize: 11 }} tickFormatter={formatShortDate} />
-                  <YAxis tick={{ fill: '#64748b', fontSize: 11 }} allowDecimals={false} />
-                  <Tooltip content={<CustomTooltip />} />
-                  <Legend formatter={(value: string) => <span className="text-xs text-ink-muted">{value}</span>} />
-                  <Line type="monotone" dataKey="completed_count" name="Completed" stroke="#10b981" strokeWidth={2} dot={false} />
-                  <Line type="monotone" dataKey="failed_count" name="Failed" stroke="#ef4444" strokeWidth={2} dot={false} />
-                </LineChart>
-              </ResponsiveContainer>
-            ) : (
-              <div className="h-full flex items-center justify-center text-sm text-ink-faint">No job trend data</div>
-            )}
-          </ChartCard>
-
-          {/* Issuance Rate (Bar chart) */}
-          <ChartCard title="Certificate Issuance Rate (30 Days)">
-            {(issuanceRate || []).length > 0 ? (
-              <ResponsiveContainer width="100%" height="100%">
-                <BarChart data={issuanceRate}>
-                  <CartesianGrid strokeDasharray="3 3" stroke="#e2e8f0" />
-                  <XAxis dataKey="date" tick={{ fill: '#64748b', fontSize: 11 }} tickFormatter={formatShortDate} />
-                  <YAxis tick={{ fill: '#64748b', fontSize: 11 }} allowDecimals={false} />
-                  <Tooltip content={<CustomTooltip />} />
-                  <Bar dataKey="issued_count" name="Issued" fill="#2ea88f" radius={[4, 4, 0, 0]} />
-                </BarChart>
-              </ResponsiveContainer>
-            ) : (
-              <div className="h-full flex items-center justify-center text-sm text-ink-faint">No issuance data</div>
-            )}
-          </ChartCard>
+          <JobTrendsLineChart data={jobTrends || []} />
+          <IssuanceRateBarChart data={issuanceRate || []} />
        </div>

        <div className="grid grid-cols-1 lg:grid-cols-2 gap-6">
@@ -1,5 +1,6 @@
 import { useState } from 'react';
-import { useQuery } from '@tanstack/react-query';
+import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { toast } from 'sonner';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
 import {
  getDiscoveredCertificates,
@@ -138,18 +139,60 @@ export default function DiscoveryPage() {
    queryFn: () => getAgents({ per_page: '200' }),
  });

-  const claimMutation = useTrackedMutation({
-    mutationFn: ({ id, managedCertId }: { id: string; managedCertId: string }) =>
+  // Phase 2 TQ-M3 closure: claim + dismiss with optimistic updates.
+  // Each one flips the row's status in the ['discovered-certificates']
+  // cache immediately so the visual response is sub-100ms regardless
+  // of network RTT. Rollback restores the snapshot + fires a Sonner
+  // error toast.
+  const queryClient = useQueryClient();
+  type DiscSnapshot = {
+    prev?: { data: DiscoveredCertificate[]; total: number } | undefined;
+  };
+
+  const claimMutation = useTrackedMutation<unknown, Error, { id: string; managedCertId: string }, DiscSnapshot>({
+    mutationFn: ({ id, managedCertId }) =>
      claimDiscoveredCertificate(id, managedCertId),
    invalidates: [['discovered-certificates'], ['discovery-summary']],
+    onMutate: async ({ id }): Promise<DiscSnapshot> => {
+      await queryClient.cancelQueries({ queryKey: ['discovered-certificates'] });
+      const prev = queryClient.getQueryData(['discovered-certificates']) as DiscSnapshot['prev'];
+      if (prev) {
+        queryClient.setQueryData(['discovered-certificates'], {
+          ...prev,
+          data: prev.data.map((c) => (c.id === id ? { ...c, status: 'Managed' as const } : c)),
+        });
+      }
+      return { prev };
+    },
+    onError: (err, _vars, snap) => {
+      if (snap?.prev) queryClient.setQueryData(['discovered-certificates'], snap.prev);
+      toast.error(`Claim failed: ${err.message}`);
+    },
    onSuccess: () => {
+      toast.success('Certificate claimed');
      setClaimingCert(null);
    },
  });

-  const dismissMutation = useTrackedMutation({
+  const dismissMutation = useTrackedMutation<unknown, Error, string, DiscSnapshot>({
    mutationFn: dismissDiscoveredCertificate,
    invalidates: [['discovered-certificates'], ['discovery-summary']],
+    onMutate: async (id): Promise<DiscSnapshot> => {
+      await queryClient.cancelQueries({ queryKey: ['discovered-certificates'] });
+      const prev = queryClient.getQueryData(['discovered-certificates']) as DiscSnapshot['prev'];
+      if (prev) {
+        queryClient.setQueryData(['discovered-certificates'], {
+          ...prev,
+          data: prev.data.map((c) => (c.id === id ? { ...c, status: 'Dismissed' as const } : c)),
+        });
+      }
+      return { prev };
+    },
+    onError: (err, _id, snap) => {
+      if (snap?.prev) queryClient.setQueryData(['discovered-certificates'], snap.prev);
+      toast.error(`Dismiss failed: ${err.message}`);
+    },
+    onSuccess: () => toast.success('Discovery dismissed'),
  });

  const formatExpiry = (notAfter?: string) => {
@@ -195,7 +238,7 @@ export default function DiscoveryPage() {
        const badge = sourceTypeBadge(c.agent_id);
        return (
          <div>
-            <span className={`inline-block px-1.5 py-0.5 rounded text-[10px] font-medium ${badge.style} mr-1`}>{badge.label}</span>
+            <span className={`inline-block px-1.5 py-0.5 rounded text-2xs font-medium ${badge.style} mr-1`}>{badge.label}</span>
            <div className="text-xs text-ink-faint truncate max-w-[180px] mt-0.5" title={c.source_path}>{c.source_path}</div>
          </div>
        );
@@ -218,7 +261,7 @@ export default function DiscoveryPage() {
        <div className="flex items-center gap-1">
          <span className="text-xs text-ink-muted">{c.key_algorithm}{c.key_size ? ` ${c.key_size}` : ''}</span>
          {c.is_ca && (
-            <span className="text-[10px] px-1.5 py-0.5 rounded bg-purple-100 text-purple-700 font-medium">CA</span>
+            <span className="text-2xs px-1.5 py-0.5 rounded bg-purple-100 text-purple-700 font-medium">CA</span>
          )}
        </div>
      ),
@@ -226,7 +269,7 @@ export default function DiscoveryPage() {
    {
      key: 'fingerprint',
      label: 'Fingerprint',
-      render: (c) => <span className="font-mono text-[10px] text-ink-faint">{c.fingerprint_sha256?.substring(0, 16)}...</span>,
+      render: (c) => <span className="font-mono text-2xs text-ink-faint">{c.fingerprint_sha256?.substring(0, 16)}...</span>,
    },
    {
      key: 'actions',
@@ -7,6 +7,7 @@ import {
  getAuditEvents,
 } from '../api/client';
 import PageHeader from '../components/PageHeader';
+import ModalDialog from '../components/ModalDialog';
 import ErrorState from '../components/ErrorState';
 import { useAuth } from '../components/AuthProvider';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
@@ -216,13 +217,13 @@ function ProfileSummaryCard({ profile, onRequestReload }: ProfileSummaryCardProp
      </header>

      <div className="flex flex-wrap gap-2 mb-3" data-testid={`est-profile-badges-${profile.path_id}`}>
-        <span className={`text-[11px] uppercase tracking-wide px-2 py-0.5 rounded border ${pillClass(profile.mtls_enabled)}`}>
+        <span className={`text-xs uppercase tracking-wide px-2 py-0.5 rounded border ${pillClass(profile.mtls_enabled)}`}>
          mTLS {profile.mtls_enabled ? 'enabled' : 'disabled'}
        </span>
-        <span className={`text-[11px] uppercase tracking-wide px-2 py-0.5 rounded border ${pillClass(profile.basic_auth_configured)}`}>
+        <span className={`text-xs uppercase tracking-wide px-2 py-0.5 rounded border ${pillClass(profile.basic_auth_configured)}`}>
          HTTP Basic {profile.basic_auth_configured ? 'configured' : 'not set'}
        </span>
-        <span className={`text-[11px] uppercase tracking-wide px-2 py-0.5 rounded border ${pillClass(profile.server_keygen_enabled)}`}>
+        <span className={`text-xs uppercase tracking-wide px-2 py-0.5 rounded border ${pillClass(profile.server_keygen_enabled)}`}>
          Server-keygen {profile.server_keygen_enabled ? 'enabled' : 'disabled'}
        </span>
      </div>
@@ -233,7 +234,7 @@ function ProfileSummaryCard({ profile, onRequestReload }: ProfileSummaryCardProp
          const value = profile.counters?.[label] ?? 0;
          return (
            <div key={label} className="bg-surface-alt rounded px-3 py-2" data-testid={`est-counter-${profile.path_id}-${label}`}>
-              <div className="text-[10px] uppercase tracking-wide text-ink-muted">{presentation.label}</div>
+              <div className="text-2xs uppercase tracking-wide text-ink-muted">{presentation.label}</div>
              <div className={`text-base font-semibold ${TONE_CLASS[presentation.tone]}`}>{value}</div>
            </div>
          );
@@ -241,7 +242,7 @@ function ProfileSummaryCard({ profile, onRequestReload }: ProfileSummaryCardProp
      </div>

      {profile.mtls_enabled && profile.trust_anchor_path && (
-        <p className="text-[11px] text-ink-muted font-mono mb-2">
+        <p className="text-xs text-ink-muted font-mono mb-2">
          Trust bundle: {profile.trust_anchor_path}
        </p>
      )}
@@ -276,30 +277,18 @@ interface ConfirmReloadModalProps {

 function ConfirmReloadModal({ profile, onCancel, onConfirm, pending, errorMessage }: ConfirmReloadModalProps) {
  const pathLabel = profile.path_id || '(legacy /.well-known/est root)';
+  // Phase 5 closure (FE-H3): swapped the inline-managed <div role="dialog">
+  // for ModalDialog (Headless UI) — focus trap + ESC-to-close + backdrop-
+  // click-to-close come for free. Existing test data-testids preserved
+  // verbatim so est-reload-cancel / est-reload-confirm / est-reload-error
+  // assertions keep working.
  return (
-    <div
-      role="dialog"
-      aria-labelledby="est-reload-trust-title"
-      aria-modal="true"
-      className="fixed inset-0 z-50 flex items-center justify-center bg-black/40"
-    >
-      <div className="bg-surface w-full max-w-md rounded-lg shadow-xl border border-surface-border p-6">
-        <h3 id="est-reload-trust-title" className="text-base font-semibold text-ink mb-2">
-          Reload EST mTLS trust anchor
-        </h3>
-        <p className="text-sm text-ink-muted mb-4">
-          This re-reads <code className="text-xs">{profile.trust_anchor_path}</code> from disk and atomically
-          swaps the trust pool for EST profile <strong>{pathLabel}</strong>. Equivalent to sending
-          <code className="text-xs"> SIGHUP </code> to the server. If the new file fails to parse, the
-          previous trust pool stays in place — enrollments keep working off the old trust anchor while you
-          fix the file.
-        </p>
-        {errorMessage && (
-          <div className="mb-3 rounded border border-red-300 bg-red-50 p-3 text-xs text-red-800" data-testid="est-reload-error">
-            {errorMessage}
-          </div>
-        )}
-        <div className="flex justify-end gap-2">
+    <ModalDialog
+      open={true}
+      title="Reload EST mTLS trust anchor"
+      onClose={pending ? () => {} : onCancel}
+      footer={
+        <>
          <button
            type="button"
            onClick={onCancel}
@@ -318,9 +307,22 @@ function ConfirmReloadModal({ profile, onCancel, onConfirm, pending, errorMessag
          >
            {pending ? 'Reloading…' : 'Reload trust anchor'}
          </button>
+        </>
+      }
+    >
+      <p className="text-sm text-ink-muted mb-3">
+        This re-reads <code className="text-xs">{profile.trust_anchor_path}</code> from disk and atomically
+        swaps the trust pool for EST profile <strong>{pathLabel}</strong>. Equivalent to sending
+        <code className="text-xs"> SIGHUP </code> to the server. If the new file fails to parse, the
+        previous trust pool stays in place — enrollments keep working off the old trust anchor while you
+        fix the file.
+      </p>
+      {errorMessage && (
+        <div className="rounded border border-red-300 bg-red-50 p-3 text-xs text-red-800" data-testid="est-reload-error">
+          {errorMessage}
        </div>
-      </div>
-    </div>
+      )}
+    </ModalDialog>
  );
 }

@@ -382,7 +382,7 @@ function SCEPProbeResultPanel({ result }: { result: SCEPProbeResult }) {
        <span>{formatDateTime(result.probed_at)} · {result.probe_duration_ms}ms</span>
      </div>
      {result.error && (
-        <p className="font-mono text-[11px] mb-2">Error: {result.error}</p>
+        <p className="font-mono text-xs mb-2">Error: {result.error}</p>
      )}
      {result.reachable && (
        <>
@@ -397,9 +397,9 @@ function SCEPProbeResultPanel({ result }: { result: SCEPProbeResult }) {
          {result.ca_cert_subject && (
            <dl className="grid grid-cols-2 gap-x-3 gap-y-1 mt-2">
              <dt className="font-semibold">CA cert subject:</dt>
-              <dd className="font-mono text-[11px]">{result.ca_cert_subject}</dd>
+              <dd className="font-mono text-xs">{result.ca_cert_subject}</dd>
              <dt className="font-semibold">Issuer:</dt>
-              <dd className="font-mono text-[11px]">{result.ca_cert_issuer}</dd>
+              <dd className="font-mono text-xs">{result.ca_cert_issuer}</dd>
              <dt className="font-semibold">Algorithm:</dt>
              <dd>{result.ca_cert_algorithm || '(unknown)'}</dd>
              <dt className="font-semibold">Chain length:</dt>
@@ -417,7 +417,7 @@ function SCEPProbeResultPanel({ result }: { result: SCEPProbeResult }) {
            </dl>
          )}
          {result.advertised_caps && result.advertised_caps.length > 0 && (
-            <p className="mt-2 text-[11px]">
+            <p className="mt-2 text-xs">
              Raw caps: <code>{result.advertised_caps.join(', ')}</code>
            </p>
          )}
@@ -430,7 +430,7 @@ function SCEPProbeResultPanel({ result }: { result: SCEPProbeResult }) {
 function CapBadge({ label, supported }: { label: string; supported: boolean }) {
  return (
    <span
-      className={`text-[11px] uppercase px-2 py-0.5 rounded border ${
+      className={`text-xs uppercase px-2 py-0.5 rounded border ${
        supported ? 'bg-emerald-100 text-emerald-800 border-emerald-300' : 'bg-gray-100 text-gray-600 border-gray-300'
      }`}
      data-testid={`scep-probe-cap-${label.toLowerCase().replace(/\W/g, '-')}`}
@@ -1,5 +1,6 @@
 import { useState, useMemo } from 'react';
-import { useQuery } from '@tanstack/react-query';
+import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { toast } from 'sonner';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
 import { getNotifications, markNotificationRead, requeueNotification } from '../api/client';
 import PageHeader from '../components/PageHeader';
@@ -8,6 +9,14 @@ import ErrorState from '../components/ErrorState';
 import { timeAgo } from '../api/utils';
 import type { Notification } from '../api/types';

+// Phase 2 TQ-M3 closure: optimistic-update context shape. onMutate
+// snapshots the current ['notifications', tab] cache; onError uses
+// it to roll back. onSettled fires the invalidation regardless.
+interface NotifSnapshot {
+  prevAll?:  { data: Notification[]; total: number } | undefined;
+  prevDead?: { data: Notification[]; total: number } | undefined;
+}
+
 type ViewMode = 'list' | 'grouped';

 // I-005: the Notifications page now hosts two tabs. "all" is the pre-I-005
@@ -43,9 +52,37 @@ export default function NotificationsPage() {
    refetchInterval: 30000,
  });

-  const markRead = useTrackedMutation({
+  // Phase 2 TQ-M3 closure: mark-notification-read with optimistic
+  // update. Flip the row's status to 'read' in the cache immediately;
+  // on error, restore the snapshot + show the toast. The success
+  // toast is omitted (the visual flip from unread → read is its own
+  // feedback); errors get a toast because they re-render the row
+  // back to unread and the operator needs to know why.
+  const queryClient = useQueryClient();
+  const markRead = useTrackedMutation<unknown, Error, string, NotifSnapshot>({
    mutationFn: markNotificationRead,
    invalidates: [['notifications']],
+    onMutate: async (id: string): Promise<NotifSnapshot> => {
+      // Cancel any in-flight refetch so optimistic data doesn't get
+      // overwritten by a stale response landing during the mutation.
+      await queryClient.cancelQueries({ queryKey: ['notifications'] });
+      const snapshot: NotifSnapshot = {
+        prevAll:  queryClient.getQueryData(['notifications', 'all'])  as NotifSnapshot['prevAll'],
+        prevDead: queryClient.getQueryData(['notifications', 'dead']) as NotifSnapshot['prevDead'],
+      };
+      const flipStatus = (page?: { data: Notification[]; total: number }) =>
+        page
+          ? { ...page, data: page.data.map((n) => (n.id === id ? { ...n, status: 'read' as const } : n)) }
+          : page;
+      queryClient.setQueryData(['notifications', 'all'],  flipStatus(snapshot.prevAll));
+      queryClient.setQueryData(['notifications', 'dead'], flipStatus(snapshot.prevDead));
+      return snapshot;
+    },
+    onError: (err, _id, snapshot) => {
+      if (snapshot?.prevAll)  queryClient.setQueryData(['notifications', 'all'],  snapshot.prevAll);
+      if (snapshot?.prevDead) queryClient.setQueryData(['notifications', 'dead'], snapshot.prevDead);
+      toast.error(`Mark-read failed: ${err.message}`);
+    },
  });

  // I-005: requeue a dead notification. Invalidates both tab cache entries
@@ -1,6 +1,7 @@
 import { useQuery } from '@tanstack/react-query';
 import { getMetrics, getPrometheusMetrics, getHealth } from '../api/client';
 import PageHeader from '../components/PageHeader';
+import Timestamp from '../components/Timestamp';
 import ErrorState from '../components/ErrorState';

 function MetricCard({ label, value, sub }: { label: string; value: string | number; sub?: string }) {
@@ -67,7 +68,7 @@ export default function ObservabilityPage() {
          </span>
          {metrics && (
            <span className="text-xs text-ink-faint ml-auto">
-              Uptime: {formatUptime(metrics.uptime.uptime_seconds)} | Started: {new Date(metrics.uptime.server_started).toLocaleString()}
+              Uptime: {formatUptime(metrics.uptime.uptime_seconds)} | Started: <Timestamp iso={metrics.uptime.server_started} />
            </span>
          )}
        </div>
@@ -1,11 +1,13 @@
 import { useEffect, useState } from 'react';
 import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { toast } from 'sonner';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
 import { getOwners, getTeams, deleteOwner, createOwner, updateOwner } from '../api/client';
 import PageHeader from '../components/PageHeader';
 import DataTable from '../components/DataTable';
 import type { Column } from '../components/DataTable';
 import ErrorState from '../components/ErrorState';
+import ConfirmDialog from '../components/ConfirmDialog';
 import { formatDateTime } from '../api/utils';
 import type { Owner, Team } from '../api/types';

@@ -211,10 +213,13 @@ export default function OwnersPage() {
    queryFn: () => getTeams(),
  });

+  const [confirmDelete, setConfirmDelete] = useState<Owner | null>(null);
+
  const deleteMutation = useTrackedMutation({
    mutationFn: deleteOwner,
    invalidates: [['owners']],
-    onError: (err: Error) => alert(`Delete failed: ${err.message}`),
+    onSuccess: () => toast.success('Owner deleted'),
+    onError: (err: Error) => toast.error(`Delete failed: ${err.message}`),
  });

  const createMutation = useTrackedMutation({
@@ -279,7 +284,7 @@ export default function OwnersPage() {
            Edit
          </button>
          <button
-            onClick={(e) => { e.stopPropagation(); if (confirm(`Delete owner ${o.name}?`)) deleteMutation.mutate(o.id); }}
+            onClick={(e) => { e.stopPropagation(); setConfirmDelete(o); }}
            className="text-xs text-red-600 hover:text-red-700 transition-colors"
          >
            Delete
@@ -329,6 +334,22 @@ export default function OwnersPage() {
        error={updateMutation.error ? (updateMutation.error as Error).message : null}
        teamsData={teamsData}
      />
+      <ConfirmDialog
+        open={confirmDelete !== null}
+        title="Delete owner"
+        message={
+          confirmDelete
+            ? `Delete owner ${confirmDelete.name}? This action cannot be undone.`
+            : ''
+        }
+        confirmLabel="Delete"
+        destructive
+        onConfirm={() => {
+          if (confirmDelete) deleteMutation.mutate(confirmDelete.id);
+          setConfirmDelete(null);
+        }}
+        onCancel={() => setConfirmDelete(null)}
+      />
    </>
  );
 }
@@ -1,5 +1,6 @@
 import { useEffect, useState } from 'react';
 import { useQuery } from '@tanstack/react-query';
+import { toast } from 'sonner';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
 import {
  getRenewalPolicies,
@@ -206,7 +207,8 @@ export default function RenewalPoliciesPage() {
    // alert so the operator sees "this policy is still attached to N
    // certificates" and can re-target those certs to another policy
    // before deleting.
-    onError: (err: Error) => alert(`Delete failed: ${err.message}`),
+    onSuccess: () => toast.success('Renewal policy deleted'),
+    onError: (err: Error) => toast.error(`Delete failed: ${err.message}`),
  });

  const columns: Column<RenewalPolicy>[] = [
@@ -8,6 +8,7 @@ import {
  getAuditEvents,
 } from '../api/client';
 import PageHeader from '../components/PageHeader';
+import ModalDialog from '../components/ModalDialog';
 import ErrorState from '../components/ErrorState';
 import { useAuth } from '../components/AuthProvider';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
@@ -207,13 +208,13 @@ function ProfileSummaryCard({ profile, onViewIntuneDetails }: ProfileSummaryCard
      </header>

      <div className="flex flex-wrap gap-2 mb-3" data-testid={`profile-badges-${profile.path_id}`}>
-        <span className={`text-[11px] uppercase tracking-wide px-2 py-0.5 rounded border ${pillClass(profile.challenge_password_set)}`}>
+        <span className={`text-xs uppercase tracking-wide px-2 py-0.5 rounded border ${pillClass(profile.challenge_password_set)}`}>
          Challenge password{profile.challenge_password_set ? ' set' : ' MISSING'}
        </span>
-        <span className={`text-[11px] uppercase tracking-wide px-2 py-0.5 rounded border ${pillClass(profile.mtls_enabled)}`}>
+        <span className={`text-xs uppercase tracking-wide px-2 py-0.5 rounded border ${pillClass(profile.mtls_enabled)}`}>
          mTLS {profile.mtls_enabled ? 'enabled' : 'disabled'}
        </span>
-        <span className={`text-[11px] uppercase tracking-wide px-2 py-0.5 rounded border ${pillClass(intuneEnabled)}`}>
+        <span className={`text-xs uppercase tracking-wide px-2 py-0.5 rounded border ${pillClass(intuneEnabled)}`}>
          Intune {intuneEnabled ? 'enabled' : 'disabled'}
        </span>
      </div>
@@ -221,7 +222,7 @@ function ProfileSummaryCard({ profile, onViewIntuneDetails }: ProfileSummaryCard
      <dl className="grid grid-cols-1 sm:grid-cols-3 gap-3 text-xs text-ink-muted">
        <div>
          <dt className="font-semibold text-ink">RA cert subject</dt>
-          <dd className="font-mono text-[11px]">{profile.ra_cert_subject || '(not loaded)'}</dd>
+          <dd className="font-mono text-xs">{profile.ra_cert_subject || '(not loaded)'}</dd>
        </div>
        {profile.ra_cert_not_after && (
          <div>
@@ -232,7 +233,7 @@ function ProfileSummaryCard({ profile, onViewIntuneDetails }: ProfileSummaryCard
        {profile.mtls_enabled && profile.mtls_trust_bundle_path && (
          <div>
            <dt className="font-semibold text-ink">mTLS trust bundle</dt>
-            <dd className="font-mono text-[11px]">{profile.mtls_trust_bundle_path}</dd>
+            <dd className="font-mono text-xs">{profile.mtls_trust_bundle_path}</dd>
          </div>
        )}
      </dl>
@@ -267,30 +268,19 @@ interface ConfirmReloadModalProps {

 function ConfirmReloadModal({ profile, onCancel, onConfirm, pending, errorMessage }: ConfirmReloadModalProps) {
  const pathLabel = profile.path_id || '(legacy /scep root)';
+  // Phase 5 closure (FE-H3): swapped the inline-managed <div role="dialog">
+  // for ModalDialog (Headless UI) so the operator gets focus trap, ESC-to-
+  // close, and backdrop-click-to-close. Pre-Phase-5 the modal had aria
+  // attrs but no focus management — Tab would escape out of the panel into
+  // the underlying page, and ESC did nothing. ModalDialog wires both to
+  // onCancel automatically.
  return (
-    <div
-      role="dialog"
-      aria-labelledby="reload-trust-title"
-      aria-modal="true"
-      className="fixed inset-0 z-50 flex items-center justify-center bg-black/40"
-    >
-      <div className="bg-surface w-full max-w-md rounded-lg shadow-xl border border-surface-border p-6">
-        <h3 id="reload-trust-title" className="text-base font-semibold text-ink mb-2">
-          Reload Intune trust anchor
-        </h3>
-        <p className="text-sm text-ink-muted mb-4">
-          This re-reads <code className="text-xs">{profile.trust_anchor_path}</code> from disk and atomically
-          swaps the trust pool for SCEP profile <strong>{pathLabel}</strong>. Equivalent to sending
-          <code className="text-xs"> SIGHUP </code> to the server. If the new file fails to parse, the
-          previous trust pool stays in place — enrollments keep working off the old trust anchor while you
-          fix the file.
-        </p>
-        {errorMessage && (
-          <div className="mb-3 rounded border border-red-300 bg-red-50 p-3 text-xs text-red-800">
-            {errorMessage}
-          </div>
-        )}
-        <div className="flex justify-end gap-2">
+    <ModalDialog
+      open={true}
+      title="Reload Intune trust anchor"
+      onClose={pending ? () => {} : onCancel}
+      footer={
+        <>
          <button
            type="button"
            onClick={onCancel}
@@ -307,9 +297,22 @@ function ConfirmReloadModal({ profile, onCancel, onConfirm, pending, errorMessag
          >
            {pending ? 'Reloading…' : 'Reload trust anchor'}
          </button>
+        </>
+      }
+    >
+      <p className="text-sm text-ink-muted mb-3">
+        This re-reads <code className="text-xs">{profile.trust_anchor_path}</code> from disk and atomically
+        swaps the trust pool for SCEP profile <strong>{pathLabel}</strong>. Equivalent to sending
+        <code className="text-xs"> SIGHUP </code> to the server. If the new file fails to parse, the
+        previous trust pool stays in place — enrollments keep working off the old trust anchor while you
+        fix the file.
+      </p>
+      {errorMessage && (
+        <div className="rounded border border-red-300 bg-red-50 p-3 text-xs text-red-800">
+          {errorMessage}
        </div>
-      </div>
-    </div>
+      )}
+    </ModalDialog>
  );
 }

@@ -416,7 +419,7 @@ function IntuneProfileCard({ profile, onRequestReload, highlighted }: IntuneProf
              <div className={`text-lg font-semibold ${TONE_CLASS[presentation.tone]}`} data-testid={`counter-${profile.path_id}-${label}`}>
                {value}
              </div>
-              <div className="text-[11px] text-ink-muted uppercase tracking-wide">{presentation.label}</div>
+              <div className="text-xs text-ink-muted uppercase tracking-wide">{presentation.label}</div>
            </div>
          );
        })}
@@ -442,7 +445,7 @@ function IntuneProfileCard({ profile, onRequestReload, highlighted }: IntuneProf
          <summary className="cursor-pointer font-semibold text-ink">Trust anchor details</summary>
          <table className="mt-2 w-full text-left">
            <thead>
-              <tr className="text-[11px] text-ink-muted uppercase">
+              <tr className="text-xs text-ink-muted uppercase">
                <th className="py-1 pr-2">Subject</th>
                <th className="py-1 pr-2">Not after</th>
                <th className="py-1">Days to expiry</th>
@@ -93,23 +93,37 @@ describe('TargetsPage — T-1 page coverage', () => {
  });

  it('Delete confirm flow calls deleteTarget(id)', async () => {
-    const origConfirm = globalThis.confirm;
-    globalThis.confirm = vi.fn(() => true);
-    try {
-      renderWithQuery(<TargetsPage />);
-      await waitFor(() => {
-        expect(screen.getByText('IIS Web01')).toBeInTheDocument();
-      });
+    // Phase 1 UX-H2 closure: Delete now opens a ConfirmDialog primitive
+    // (Headless UI) rather than firing window.confirm(). The new flow:
+    //   1. operator clicks the row's "Delete" button → sets state
+    //      that opens the dialog
+    //   2. ConfirmDialog mounts with title "Delete deployment target"
+    //   3. operator clicks the dialog's destructive "Delete" button
+    //   4. deleteTarget(id) fires
+    renderWithQuery(<TargetsPage />);
+    await waitFor(() => {
+      expect(screen.getByText('IIS Web01')).toBeInTheDocument();
+    });

-      const deleteButtons = await screen.findAllByRole('button', { name: 'Delete' });
-      fireEvent.click(deleteButtons[0]!);
+    const rowDeleteButtons = await screen.findAllByRole('button', { name: 'Delete' });
+    fireEvent.click(rowDeleteButtons[0]!);

-      await waitFor(() => {
-        expect(client.deleteTarget).toHaveBeenCalled();
-      });
-      expect(vi.mocked(client.deleteTarget).mock.calls[0]?.[0]).toBe('tgt-iis-prod');
-    } finally {
-      globalThis.confirm = origConfirm;
-    }
+    // Wait for the dialog title to mount (Headless UI Transition).
+    await waitFor(() => {
+      expect(screen.getByText('Delete deployment target')).toBeInTheDocument();
+    });
+
+    // Click the dialog's destructive-styled confirm button (.btn-danger).
+    const allDeleteButtons = await screen.findAllByRole('button', { name: 'Delete' });
+    const dialogDeleteBtn = allDeleteButtons.find((b) =>
+      b.className.includes('btn-danger'),
+    );
+    expect(dialogDeleteBtn).toBeDefined();
+    fireEvent.click(dialogDeleteBtn!);
+
+    await waitFor(() => {
+      expect(client.deleteTarget).toHaveBeenCalled();
+    });
+    expect(vi.mocked(client.deleteTarget).mock.calls[0]?.[0]).toBe('tgt-iis-prod');
  });
 });
@@ -1,6 +1,7 @@
 import { useState } from 'react';
 import { Link } from 'react-router-dom';
 import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { toast } from 'sonner';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
 import { getTargets, createTarget, deleteTarget, getAgents } from '../api/client';
 import PageHeader from '../components/PageHeader';
@@ -8,6 +9,7 @@ import DataTable from '../components/DataTable';
 import type { Column } from '../components/DataTable';
 import StatusBadge from '../components/StatusBadge';
 import ErrorState from '../components/ErrorState';
+import ConfirmDialog from '../components/ConfirmDialog';
 import { formatDateTime } from '../api/utils';
 import type { Target } from '../api/types';

@@ -403,6 +405,7 @@ function CreateTargetWizard({ onClose, onSuccess }: { onClose: () => void; onSuc
 export default function TargetsPage() {
  const queryClient = useQueryClient();
  const [showCreate, setShowCreate] = useState(false);
+  const [confirmDelete, setConfirmDelete] = useState<Target | null>(null);

  const { data, isLoading, error, refetch } = useQuery({
    queryKey: ['targets'],
@@ -412,6 +415,8 @@ export default function TargetsPage() {
  const deleteMutation = useTrackedMutation({
    mutationFn: deleteTarget,
    invalidates: [['targets']],
+    onSuccess: () => toast.success('Target deleted'),
+    onError: (err: Error) => toast.error(`Delete failed: ${err.message}`),
  });

  const columns: Column<Target>[] = [
@@ -462,7 +467,7 @@ export default function TargetsPage() {
      label: '',
      render: (t) => (
        <button
-          onClick={(e) => { e.stopPropagation(); if (confirm(`Delete target ${t.name}?`)) deleteMutation.mutate(t.id); }}
+          onClick={(e) => { e.stopPropagation(); setConfirmDelete(t); }}
          className="text-xs text-red-600 hover:text-red-700 transition-colors"
        >
          Delete
@@ -498,6 +503,22 @@ export default function TargetsPage() {
          }}
        />
      )}
+      <ConfirmDialog
+        open={confirmDelete !== null}
+        title="Delete deployment target"
+        message={
+          confirmDelete
+            ? `Delete target ${confirmDelete.name}? Active deployments referencing this target will fail until reconfigured.`
+            : ''
+        }
+        confirmLabel="Delete"
+        destructive
+        onConfirm={() => {
+          if (confirmDelete) deleteMutation.mutate(confirmDelete.id);
+          setConfirmDelete(null);
+        }}
+        onCancel={() => setConfirmDelete(null)}
+      />
    </>
  );
 }
@@ -1,5 +1,6 @@
 import { useEffect, useState } from 'react';
 import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { toast } from 'sonner';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
 import { getTeams, deleteTeam, createTeam, updateTeam } from '../api/client';
 import PageHeader from '../components/PageHeader';
@@ -156,7 +157,8 @@ export default function TeamsPage() {
  const deleteMutation = useTrackedMutation({
    mutationFn: deleteTeam,
    invalidates: [['teams']],
-    onError: (err: Error) => alert(`Delete failed: ${err.message}`),
+    onSuccess: () => toast.success('Team deleted'),
+    onError: (err: Error) => toast.error(`Delete failed: ${err.message}`),
  });

  const createMutation = useTrackedMutation({
@@ -9,7 +9,9 @@ import {
 } from '../../api/client';
 import { useAuthMe } from '../../hooks/useAuthMe';
 import PageHeader from '../../components/PageHeader';
+import Timestamp from '../../components/Timestamp';
 import ErrorState from '../../components/ErrorState';
+import { STALE_TIME } from '../../api/queryConstants';

 // =============================================================================
 // Bundle 1 Phase 9 + Phase 10 — Approvals queue.
@@ -239,7 +241,7 @@ export default function ApprovalsPage() {
  const query = useQuery({
    queryKey: ['approvals', filterState],
    queryFn: () => listApprovals(filterState),
-    staleTime: 15_000,
+    staleTime: STALE_TIME.REAL_TIME,   // approval queue — operator-facing
    refetchInterval: 30_000,
  });

@@ -374,7 +376,7 @@ export default function ApprovalsPage() {
                        {isMine && <span className="ml-2 text-amber-700">(you)</span>}
                      </td>
                      <td className="px-3 py-2 text-xs text-ink-muted">
-                        {new Date(req.created_at).toLocaleString()}
+                        <Timestamp iso={req.created_at} />
                      </td>
                      <td className="px-3 py-2">
                        {/* Audit 2026-05-11 A-5 — payload preview toggle.
@@ -1,7 +1,10 @@
+import { useState } from 'react';
 import { useQuery } from '@tanstack/react-query';
 import { authBootstrapAvailable, authRuntimeConfig } from '../../api/client';
 import { useAuthMe } from '../../hooks/useAuthMe';
 import PageHeader from '../../components/PageHeader';
+import { STALE_TIME } from '../../api/queryConstants';
+import { getTimestampPref, setTimestampPref, type TimestampMode } from '../../api/timestampPref';

 // =============================================================================
 // Bundle 1 Phase 10 — AuthSettingsPage (stub).
@@ -24,7 +27,7 @@ export default function AuthSettingsPage() {
  const bootstrapQuery = useQuery({
    queryKey: ['auth', 'bootstrap', 'available'],
    queryFn: authBootstrapAvailable,
-    staleTime: 60_000,
+    staleTime: STALE_TIME.REFERENCE,   // slow-changing auth-runtime data
    retry: 0,
  });
  // Audit 2026-05-10 MED-12 — Auth runtime config panel. Gated
@@ -33,7 +36,7 @@ export default function AuthSettingsPage() {
  const runtimeQuery = useQuery({
    queryKey: ['auth', 'runtime-config'],
    queryFn: authRuntimeConfig,
-    staleTime: 60_000,
+    staleTime: STALE_TIME.REFERENCE,   // slow-changing auth-runtime data
    retry: 0,
  });

@@ -163,6 +166,67 @@ export default function AuthSettingsPage() {
          </div>
        </section>
      )}
+
+      {/* Phase 6 closure (I18N-H3): operator timestamp-display preference. */}
+      <TimestampPreferenceCard />
    </div>
  );
 }
+
+// ──────────────────────────────────────────────────────────────────
+// Timestamp-display preference (Phase 6 I18N-H3)
+// ──────────────────────────────────────────────────────────────────
+
+function TimestampPreferenceCard() {
+  const [mode, setMode] = useState<TimestampMode>(() => getTimestampPref().mode);
+  const [customTz, setCustomTz] = useState<string>(() => getTimestampPref().customTz);
+
+  function persist(next: { mode: TimestampMode; customTz: string }) {
+    setMode(next.mode);
+    setCustomTz(next.customTz);
+    setTimestampPref(next);
+  }
+
+  return (
+    <section className="bg-surface border border-surface-border rounded shadow-sm" data-testid="timestamp-pref-card">
+      <div className="px-4 py-3 border-b border-surface-border">
+        <div className="text-sm font-semibold">Timestamp display</div>
+        <div className="text-xs text-ink-muted">
+          Default UTC matches the server audit log byte-for-byte. Pick Local for browser time;
+          Custom for a specific IANA timezone (e.g. <code>America/New_York</code>).
+        </div>
+      </div>
+      <div className="px-4 py-3 text-sm space-y-3">
+        <div className="flex items-center gap-4">
+          {(['utc', 'local', 'custom'] as const).map((m) => (
+            <label key={m} className="flex items-center gap-1.5 cursor-pointer">
+              <input
+                type="radio"
+                name="timestamp-mode"
+                value={m}
+                checked={mode === m}
+                onChange={() => persist({ mode: m, customTz })}
+                data-testid={`timestamp-mode-${m}`}
+              />
+              <span className="capitalize">{m === 'utc' ? 'UTC' : m}</span>
+            </label>
+          ))}
+        </div>
+        {mode === 'custom' && (
+          <div>
+            <label className="block text-xs font-medium text-ink-muted mb-1">IANA timezone</label>
+            <input
+              type="text"
+              value={customTz}
+              onChange={(e) => persist({ mode, customTz: e.target.value })}
+              placeholder="America/New_York"
+              spellCheck={false}
+              className="w-full px-2 py-1 border border-surface-border rounded bg-page text-ink font-mono text-xs"
+              data-testid="timestamp-custom-tz-input"
+            />
+          </div>
+        )}
+      </div>
+    </section>
+  );
+}
@@ -10,6 +10,7 @@ import {
 } from '../../api/client';
 import { useAuthMe } from '../../hooks/useAuthMe';
 import PageHeader from '../../components/PageHeader';
+import Timestamp from '../../components/Timestamp';
 import ErrorState from '../../components/ErrorState';

 // =============================================================================
@@ -232,7 +233,7 @@ export default function BreakglassPage() {
                      >
                        <td className="py-3 font-mono text-xs">{row.actor_id}</td>
                        <td className="py-3 text-xs text-ink-muted">
-                          {new Date(row.last_password_change_at).toLocaleString()}
+                          <Timestamp iso={row.last_password_change_at} />
                        </td>
                        <td className="py-3 text-xs">
                          {row.failure_count > 0 ? (
@@ -244,7 +245,7 @@ export default function BreakglassPage() {
                        <td className="py-3 text-xs text-ink-muted">
                          {isLocked ? (
                            <span className="text-red-700">
-                              {new Date(row.locked_until!).toLocaleString()}
+                              <Timestamp iso={row.locked_until!} />
                            </span>
                          ) : (
                            '—'
@@ -11,6 +11,7 @@ import {
 import { useAuthMe } from '../../hooks/useAuthMe';
 import PageHeader from '../../components/PageHeader';
 import ErrorState from '../../components/ErrorState';
+import { formatDate } from '../../api/utils';

 // =============================================================================
 // Bundle 2 Phase 8 — GroupMappingsPage.
@@ -203,7 +204,7 @@ export default function GroupMappingsPage() {
                  <td className="px-4 py-2 font-mono text-xs">{m.group_name}</td>
                  <td className="px-4 py-2 font-mono text-xs">{m.role_id}</td>
                  <td className="px-4 py-2 text-ink-muted">
-                    {m.created_at ? new Date(m.created_at).toLocaleDateString() : '—'}
+                    {formatDate(m.created_at)}
                  </td>
                  <td className="px-4 py-2 text-right">
                    {canEdit && (
@@ -1,5 +1,6 @@
 import { useState } from 'react';
 import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { toast } from 'sonner';
 import {
  authListKeys,
  authListRoles,
@@ -11,6 +12,8 @@ import {
 import { useAuthMe } from '../../hooks/useAuthMe';
 import PageHeader from '../../components/PageHeader';
 import ErrorState from '../../components/ErrorState';
+import ConfirmDialog from '../../components/ConfirmDialog';
+import { STALE_TIME } from '../../api/queryConstants';

 // =============================================================================
 // Bundle 1 Phase 10 — KeysPage.
@@ -33,31 +36,44 @@ export default function KeysPage() {
  const keysQuery = useQuery<AuthKeyEntry[], Error>({
    queryKey: ['auth', 'keys'],
    queryFn: authListKeys,
-    staleTime: 30_000,
+    staleTime: STALE_TIME.REAL_TIME,   // operator-facing live data
  });
  const rolesQuery = useQuery<AuthRole[], Error>({
    queryKey: ['auth', 'roles'],
    queryFn: authListRoles,
-    staleTime: 60_000,
+    staleTime: STALE_TIME.REFERENCE,   // role catalogue, slow-changing
  });

  const [assignTarget, setAssignTarget] = useState<AuthKeyEntry | null>(null);
  const [actionError, setActionError] = useState<string | null>(null);
  const [busy, setBusy] = useState(false);
+  // UX-H2 closure — replace window.confirm() with ConfirmDialog.
+  const [confirmRevoke, setConfirmRevoke] = useState<
+    { entry: AuthKeyEntry; roleID: string } | null
+  >(null);

  const canAssign = me.hasPerm('auth.role.assign') || me.isAdmin();
  const canRevoke = me.hasPerm('auth.role.assign') || me.isAdmin();

-  const handleRevoke = async (entry: AuthKeyEntry, roleID: string) => {
+  const handleRevoke = (entry: AuthKeyEntry, roleID: string) => {
    if (entry.actor_id === DEMO_ANON) return;
-    if (!window.confirm(`Revoke ${roleID} from ${entry.actor_id}?`)) return;
+    setConfirmRevoke({ entry, roleID });
+  };
+
+  const performRevoke = async () => {
+    if (!confirmRevoke) return;
+    const { entry, roleID } = confirmRevoke;
+    setConfirmRevoke(null);
    setBusy(true);
    setActionError(null);
    try {
      await authRevokeKeyRole(entry.actor_id, roleID);
+      toast.success(`Revoked ${roleID} from ${entry.actor_id}`);
      qc.invalidateQueries({ queryKey: ['auth', 'keys'] });
    } catch (err) {
-      setActionError(err instanceof Error ? err.message : String(err));
+      const msg = err instanceof Error ? err.message : String(err);
+      setActionError(msg);
+      toast.error(`Revoke failed: ${msg}`);
    } finally {
      setBusy(false);
    }
@@ -173,6 +189,19 @@ export default function KeysPage() {
          }}
        />
      )}
+      <ConfirmDialog
+        open={confirmRevoke !== null}
+        title="Revoke role grant"
+        message={
+          confirmRevoke
+            ? `Revoke ${confirmRevoke.roleID} from ${confirmRevoke.entry.actor_id}? The actor will lose every permission scoped to that role on the next request.`
+            : ''
+        }
+        confirmLabel="Revoke"
+        destructive
+        onConfirm={performRevoke}
+        onCancel={() => setConfirmRevoke(null)}
+      />
    </div>
  );
 }
@@ -5,6 +5,7 @@ import {
  refreshOIDCProvider,
  type JWKSStatusSnapshot,
 } from '../../api/client';
+import { STALE_TIME } from '../../api/queryConstants';

 // =============================================================================
 // Audit 2026-05-11 Fix 10 — JWKS health panel (MED-7 GUI half).
@@ -69,7 +70,7 @@ export default function OIDCJWKSStatusPanel({ providerID, canRefresh = true }: P
    queryKey: ['auth', 'oidc', 'jwks-status', providerID],
    queryFn: () => authOIDCJWKSStatus(providerID),
    // 30s freshness — operators rarely poll faster than this.
-    staleTime: 30_000,
+    staleTime: STALE_TIME.REAL_TIME,   // operator troubleshooting key rotation
    // 403 / 404 / 500 — don't drown the page in retries. The panel
    // hides itself on error (see below).
    retry: 0,
@@ -11,6 +11,7 @@ import { useAuthMe } from '../../hooks/useAuthMe';
 import PageHeader from '../../components/PageHeader';
 import ErrorState from '../../components/ErrorState';
 import OIDCTestConnectionPanel from './OIDCTestConnectionPanel';
+import { formatDate } from '../../api/utils';

 // =============================================================================
 // Bundle 2 Phase 8 — OIDCProvidersPage.
@@ -431,7 +432,7 @@ export default function OIDCProvidersPage() {
                  <td className="px-4 py-2 text-ink-muted font-mono text-xs">{p.issuer_url}</td>
                  <td className="px-4 py-2 text-ink-muted font-mono text-xs">{p.client_id}</td>
                  <td className="px-4 py-2 text-ink-muted">
-                    {p.created_at ? new Date(p.created_at).toLocaleDateString() : '—'}
+                    {formatDate(p.created_at)}
                  </td>
                </tr>
              ))}
@@ -1,6 +1,7 @@
 import { useState } from 'react';
 import { Link, useParams, useNavigate } from 'react-router-dom';
 import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { toast } from 'sonner';
 import {
  authGetRole,
  authListPermissions,
@@ -13,6 +14,8 @@ import {
 import { useAuthMe } from '../../hooks/useAuthMe';
 import PageHeader from '../../components/PageHeader';
 import ErrorState from '../../components/ErrorState';
+import ConfirmDialog from '../../components/ConfirmDialog';
+import { STALE_TIME } from '../../api/queryConstants';

 // =============================================================================
 // Bundle 1 Phase 10 — RoleDetailPage.
@@ -54,17 +57,19 @@ export default function RoleDetailPage() {
    queryKey: ['auth', 'role', id],
    queryFn: () => authGetRole(id),
    enabled: Boolean(id),
-    staleTime: 30_000,
+    staleTime: STALE_TIME.REAL_TIME,    // operator editing — fresh data
  });
  const permsCatalogue = useQuery<AuthPermission[], Error>({
    queryKey: ['auth', 'permissions'],
    queryFn: authListPermissions,
-    staleTime: 5 * 60_000,
+    staleTime: STALE_TIME.CONSTANT,     // catalogue — effectively immutable
  });

  const [editOpen, setEditOpen] = useState(false);
  const [submitting, setSubmitting] = useState(false);
  const [actionError, setActionError] = useState<string | null>(null);
+  // UX-H2 closure — replace window.confirm with ConfirmDialog.
+  const [confirmDelete, setConfirmDelete] = useState(false);

  const canEdit = me.hasPerm('auth.role.edit') || me.isAdmin();
  const canDelete = me.hasPerm('auth.role.delete') || me.isAdmin();
@@ -83,15 +88,22 @@ export default function RoleDetailPage() {

  const { role, permissions } = detailQuery.data;

-  const handleDelete = async () => {
-    if (!window.confirm(`Delete role ${role.name}? This cannot be undone.`)) return;
+  const handleDelete = () => {
+    setConfirmDelete(true);
+  };
+
+  const performDelete = async () => {
+    setConfirmDelete(false);
    setSubmitting(true);
    setActionError(null);
    try {
      await authDeleteRole(role.id);
+      toast.success(`Role ${role.name} deleted`);
      navigate('/auth/roles');
    } catch (err) {
-      setActionError(err instanceof Error ? err.message : String(err));
+      const msg = err instanceof Error ? err.message : String(err);
+      setActionError(msg);
+      toast.error(`Delete failed: ${msg}`);
    } finally {
      setSubmitting(false);
    }
@@ -260,6 +272,15 @@ export default function RoleDetailPage() {
          }}
        />
      )}
+      <ConfirmDialog
+        open={confirmDelete}
+        title="Delete role"
+        message={`Delete role ${role.name}? Every actor currently holding this role grant will lose those permissions. This cannot be undone.`}
+        confirmLabel="Delete role"
+        destructive
+        onConfirm={performDelete}
+        onCancel={() => setConfirmDelete(false)}
+      />
    </div>
  );
 }
@@ -5,6 +5,7 @@ import { authListRoles, authCreateRole, type AuthRole } from '../../api/client';
 import { useAuthMe } from '../../hooks/useAuthMe';
 import PageHeader from '../../components/PageHeader';
 import ErrorState from '../../components/ErrorState';
+import { STALE_TIME } from '../../api/queryConstants';

 // =============================================================================
 // Bundle 1 Phase 10 — RolesPage.
@@ -139,7 +140,7 @@ export default function RolesPage() {
  const rolesQuery = useQuery<AuthRole[], Error>({
    queryKey: ['auth', 'roles'],
    queryFn: authListRoles,
-    staleTime: 30_000,
+    staleTime: STALE_TIME.REFERENCE,   // role catalogue — slow-changing
  });

  const [createOpen, setCreateOpen] = useState(false);
@@ -3,6 +3,7 @@ import { useQuery, useQueryClient } from '@tanstack/react-query';
 import { listSessions, revokeSession, type SessionInfo } from '../../api/client';
 import { useAuthMe } from '../../hooks/useAuthMe';
 import PageHeader from '../../components/PageHeader';
+import Timestamp from '../../components/Timestamp';
 import ErrorState from '../../components/ErrorState';

 // =============================================================================
@@ -166,7 +167,7 @@ export default function SessionsPage() {
                      <span className="ml-1 text-ink-muted">({s.actor_type})</span>
                      {isOwn && (
                        <span
-                          className="ml-2 inline-block px-1.5 py-0.5 text-[10px] rounded bg-brand-50 text-brand-700"
+                          className="ml-2 inline-block px-1.5 py-0.5 text-2xs rounded bg-brand-50 text-brand-700"
                          data-testid={`session-self-pill-${s.id}`}
                        >
                          you
@@ -175,10 +176,10 @@ export default function SessionsPage() {
                    </td>
                    <td className="px-4 py-2 text-ink-muted">{s.ip_address || '—'}</td>
                    <td className="px-4 py-2 text-ink-muted">
-                      {s.last_seen_at ? new Date(s.last_seen_at).toLocaleString() : '—'}
+                      <Timestamp iso={s.last_seen_at} />
                    </td>
                    <td className="px-4 py-2 text-ink-muted">
-                      {s.absolute_expires_at ? new Date(s.absolute_expires_at).toLocaleString() : '—'}
+                      <Timestamp iso={s.absolute_expires_at} />
                    </td>
                    <td className="px-4 py-2 text-right">
                      {showRevoke && (
--- a/Show More
+++ b/Show More