diff --git a/docs/release-control/v6/internal/subsystems/deployment-installability.md b/docs/release-control/v6/internal/subsystems/deployment-installability.md
index 080b95e4d..f2ab791bf 100644
--- a/docs/release-control/v6/internal/subsystems/deployment-installability.md
+++ b/docs/release-control/v6/internal/subsystems/deployment-installability.md
@@ -200,6 +200,11 @@ across pretest, Playwright, and posttest. `scripts/hot-dev.sh` must honor that
 lock by suppressing source-triggered rebuilds and manual `pulse` binary restart
 churn while the owning proof process is still alive. Stale verify locks must
 clear themselves automatically once the owning process exits.
+That same verification contract also applies before Playwright attaches: if a
+managed hot-dev session is already running when the verify lock is active, the
+integration launcher must restart that session instead of silently attaching to
+an old frontend process, so browser proof reflects the current branch-tip
+source rather than whatever Vite shell happened to be left alive.
 That same launcher boundary also owns its CLI contract: managed commands such
 as `start --takeover` and `restart --takeover` must preserve the takeover flag
 through the actual script entrypoint instead of silently dropping second-arg
diff --git a/scripts/tests/test-hot-dev-bg.sh b/scripts/tests/test-hot-dev-bg.sh
index ab2da68f4..1a7b8101c 100755
--- a/scripts/tests/test-hot-dev-bg.sh
+++ b/scripts/tests/test-hot-dev-bg.sh
@@ -243,6 +243,36 @@ test_verify_bg_holds_runtime_lock_for_proof_duration() {
   assert_contains "verify clears the runtime lock after proofs finish" "${output}" "lock_after=no"
 }
 
+test_managed_dev_runtime_restarts_existing_session_for_verification() {
+  local output
+  output="$(
+    ROOT_DIR="${ROOT_DIR}" \
+    node --input-type=module <<'EOF'
+import fs from 'node:fs/promises';
+import os from 'node:os';
+import path from 'node:path';
+
+const rootDir = process.env.ROOT_DIR;
+const modulePath = path.join(rootDir, 'tests', 'integration', 'scripts', 'managed-dev-runtime.mjs');
+const { shouldRestartManagedDevRuntimeForVerification } = await import(`file://${modulePath}`);
+
+const tempDir = await fs.mkdtemp(path.join(os.tmpdir(), 'pulse-managed-dev-verify-'));
+const lockPath = path.join(tempDir, 'hot-dev.verify.lock');
+await fs.writeFile(lockPath, `pid=${process.pid}\ncreated_at=2026-03-28T23:00:00Z\n`, 'utf8');
+
+console.log(
+  `running=${shouldRestartManagedDevRuntimeForVerification({ env: { HOT_DEV_VERIFY_LOCK_FILE: lockPath }, wasRunning: true })}`,
+);
+console.log(
+  `stopped=${shouldRestartManagedDevRuntimeForVerification({ env: { HOT_DEV_VERIFY_LOCK_FILE: lockPath }, wasRunning: false })}`,
+);
+EOF
+  )"
+
+  assert_contains "managed dev runtime restarts existing sessions during verification" "${output}" "running=true"
+  assert_contains "managed dev runtime does not restart absent prior session" "${output}" "stopped=false"
+}
+
 test_takeover_avoids_killing_current_shell_lineage() {
   local output
   output="$(
@@ -865,6 +895,7 @@ main() {
   test_verify_command_injects_managed_runtime_env
   test_default_verify_command_runs_runtime_and_layout_proofs
   test_verify_bg_holds_runtime_lock_for_proof_duration
+  test_managed_dev_runtime_restarts_existing_session_for_verification
   test_takeover_avoids_killing_current_shell_lineage
   test_launchd_session_supervises_managed_runtime
   test_start_bg_reports_browser_entrypoint
diff --git a/tests/integration/scripts/managed-dev-runtime.mjs b/tests/integration/scripts/managed-dev-runtime.mjs
index fd0cbb53c..d389ce594 100644
--- a/tests/integration/scripts/managed-dev-runtime.mjs
+++ b/tests/integration/scripts/managed-dev-runtime.mjs
@@ -1,3 +1,4 @@
+import fs from 'node:fs';
 import { spawn } from 'node:child_process';
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
@@ -18,6 +19,10 @@ function hotDevBgScriptPath(env = process.env) {
   return path.join(repoRootFromEnv(env), 'scripts', 'hot-dev-bg.sh');
 }
 
+function managedVerifyLockPath(env = process.env) {
+  return trim(env.HOT_DEV_VERIFY_LOCK_FILE) || path.join(repoRootFromEnv(env), 'tmp', 'hot-dev.verify.lock');
+}
+
 function hotDevBrowserURL(env = process.env) {
   const host = trim(env.FRONTEND_DEV_HOST) || '127.0.0.1';
   const port = trim(env.FRONTEND_DEV_PORT) || '5173';
@@ -63,6 +68,32 @@ function statusReportsRunning(output) {
   return output.includes('[hot-dev-bg] Running');
 }
 
+export function managedVerifyLockActive(env = process.env) {
+  try {
+    const raw = fs.readFileSync(managedVerifyLockPath(env), 'utf8');
+    const ownerPid = Number.parseInt(
+      raw
+        .split('\n')
+        .find((line) => line.startsWith('pid='))?.slice(4) || '',
+      10,
+    );
+    if (!Number.isInteger(ownerPid) || ownerPid <= 0) {
+      return false;
+    }
+    process.kill(ownerPid, 0);
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+export function shouldRestartManagedDevRuntimeForVerification({
+  env = process.env,
+  wasRunning,
+}) {
+  return Boolean(wasRunning) && managedVerifyLockActive(env);
+}
+
 async function managedRuntimeStatusOutput(env = process.env) {
   const status = await runHotDevBg(['status'], env);
   if (status.code !== 0) {
@@ -231,14 +262,21 @@ export async function startManagedDevRuntime({
     throw new Error(`hot-dev-bg status failed before start: ${statusBefore.stderr || statusBefore.stdout}`);
   }
   const wasRunning = statusReportsRunning(`${statusBefore.stdout}${statusBefore.stderr}`);
+  const shouldRestartForVerification = shouldRestartManagedDevRuntimeForVerification({
+    env,
+    wasRunning,
+  });
 
-  const startArgs = ['start'];
+  const startArgs = [shouldRestartForVerification ? 'restart' : 'start'];
   if (truthy(env.PULSE_E2E_HOT_DEV_TAKEOVER)) {
     startArgs.push('--takeover');
   }
+  if (shouldRestartForVerification) {
+    logger.log('[integration] Restarting managed dev runtime before browser verification to pick up current source changes');
+  }
   const startResult = await runHotDevBg(startArgs, env);
   if (startResult.code !== 0) {
-    throw new Error(`hot-dev-bg start failed: ${startResult.stderr || startResult.stdout}`);
+    throw new Error(`hot-dev-bg ${startArgs[0]} failed: ${startResult.stderr || startResult.stdout}`);
   }
 
   await waitForStableManagedRuntime({ env });
diff --git a/tests/integration/scripts/managed-dev-runtime.test.mjs b/tests/integration/scripts/managed-dev-runtime.test.mjs
new file mode 100644
index 000000000..70ade3ce5
--- /dev/null
+++ b/tests/integration/scripts/managed-dev-runtime.test.mjs
@@ -0,0 +1,47 @@
+import assert from 'node:assert/strict';
+import fs from 'node:fs/promises';
+import os from 'node:os';
+import path from 'node:path';
+import test from 'node:test';
+
+import {
+  managedVerifyLockActive,
+  shouldRestartManagedDevRuntimeForVerification,
+} from './managed-dev-runtime.mjs';
+
+test('managedVerifyLockActive returns true for a live verify lock owner', async () => {
+  const rootDir = await fs.mkdtemp(path.join(os.tmpdir(), 'pulse-managed-dev-runtime-'));
+  const lockPath = path.join(rootDir, 'hot-dev.verify.lock');
+  await fs.writeFile(lockPath, `pid=${process.pid}\ncreated_at=2026-03-28T23:00:00Z\n`, 'utf8');
+
+  assert.equal(managedVerifyLockActive({ HOT_DEV_VERIFY_LOCK_FILE: lockPath }), true);
+});
+
+test('managedVerifyLockActive clears false when the verify lock owner is stale', async () => {
+  const rootDir = await fs.mkdtemp(path.join(os.tmpdir(), 'pulse-managed-dev-runtime-'));
+  const lockPath = path.join(rootDir, 'hot-dev.verify.lock');
+  await fs.writeFile(lockPath, 'pid=999999\ncreated_at=2026-03-28T23:00:00Z\n', 'utf8');
+
+  assert.equal(managedVerifyLockActive({ HOT_DEV_VERIFY_LOCK_FILE: lockPath }), false);
+});
+
+test('shouldRestartManagedDevRuntimeForVerification only restarts existing sessions under verify lock', async () => {
+  const rootDir = await fs.mkdtemp(path.join(os.tmpdir(), 'pulse-managed-dev-runtime-'));
+  const lockPath = path.join(rootDir, 'hot-dev.verify.lock');
+  await fs.writeFile(lockPath, `pid=${process.pid}\ncreated_at=2026-03-28T23:00:00Z\n`, 'utf8');
+
+  assert.equal(
+    shouldRestartManagedDevRuntimeForVerification({
+      env: { HOT_DEV_VERIFY_LOCK_FILE: lockPath },
+      wasRunning: true,
+    }),
+    true,
+  );
+  assert.equal(
+    shouldRestartManagedDevRuntimeForVerification({
+      env: { HOT_DEV_VERIFY_LOCK_FILE: lockPath },
+      wasRunning: false,
+    }),
+    false,
+  );
+});