From f4338c9d6bffd8673962e8896874c69bf078762a Mon Sep 17 00:00:00 2001
From: Anso <dev@saelix.com>
Date: Tue, 28 Apr 2026 09:15:54 -0400
Subject: [PATCH] perf(build): enable incremental tsc (#827)
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backend/tsconfig.json had no incremental setting, so every tsc run
re-checked the full project from cold. The two frontend tsconfigs
already declared a tsBuildInfoFile path under node_modules/.tmp/ but
without incremental: true the file was never written, and the path
itself sits inside node_modules where npm ci wipes it on every fresh
install — neither of which actually persists incremental state.

Add incremental: true to all three configs and drop the broken
tsBuildInfoFile overrides. TypeScript's default places the buildinfo
next to the tsconfig (e.g. backend/tsconfig.tsbuildinfo); the root
.gitignore already covers *.tsbuildinfo so nothing leaks into git.

Local cold-vs-warm tsc --noEmit on the backend dropped from ~3.0s
to ~1.4s — ~2x speedup on the warm path. CI builds are still cold
because runners do not cache the buildinfo between jobs; that is a
separate workflow change.
---
 backend/tsconfig.json       | 3 ++-
 frontend/tsconfig.app.json  | 2 +-
 frontend/tsconfig.node.json | 2 +-
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/backend/tsconfig.json b/backend/tsconfig.json
index 7a102071..d868830e 100644
--- a/backend/tsconfig.json
+++ b/backend/tsconfig.json
@@ -9,7 +9,8 @@
     "esModuleInterop": true,
     "skipLibCheck": true,
     "forceConsistentCasingInFileNames": true,
-    "resolveJsonModule": true
+    "resolveJsonModule": true,
+    "incremental": true
   },
   "include": ["src/**/*"],
   "exclude": ["node_modules", "dist"]
diff --git a/frontend/tsconfig.app.json b/frontend/tsconfig.app.json
index 60a86638..043c080d 100644
--- a/frontend/tsconfig.app.json
+++ b/frontend/tsconfig.app.json
@@ -1,6 +1,6 @@
 {
   "compilerOptions": {
-    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.app.tsbuildinfo",
+    "incremental": true,
     "target": "ES2022",
     "useDefineForClassFields": true,
     "lib": ["ES2022", "DOM", "DOM.Iterable"],
diff --git a/frontend/tsconfig.node.json b/frontend/tsconfig.node.json
index 8a67f62f..9a176d11 100644
--- a/frontend/tsconfig.node.json
+++ b/frontend/tsconfig.node.json
@@ -1,6 +1,6 @@
 {
   "compilerOptions": {
-    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.node.tsbuildinfo",
+    "incremental": true,
     "target": "ES2023",
     "lib": ["ES2023"],
     "module": "ESNext",