perf(website-server): Enable Node.js compile cache for faster cold starts

website/server/Dockerfile

@@ -44,11 +44,20 @@ COPY --from=builder /app/dist-bundled ./dist-bundled
 COPY --from=builder /app/node_modules/tinypool ./node_modules/tinypool
 COPY --from=builder /app/node_modules/tiktoken ./node_modules/tiktoken
 
+# Copy warmup script for compile cache generation
+COPY --from=builder /app/warmup.mjs ./warmup.mjs
+
 # Set environment variables for bundled mode
+# NODE_COMPILE_CACHE enables V8 compile cache to reduce cold start latency
 ENV NODE_ENV=production \
     PORT=8080 \
     REPOMIX_WORKER_PATH=/app/dist-bundled/server.mjs \
-    REPOMIX_WASM_DIR=/app/dist-bundled/wasm
+    REPOMIX_WASM_DIR=/app/dist-bundled/wasm \
+    NODE_COMPILE_CACHE=/app/.compile-cache
+
+# Generate compile cache at build time
+# This pre-compiles all modules so cold starts use cached compiled code
+RUN node warmup.mjs
 
 # Expose port
 EXPOSE 8080

website/server/src/index.ts

@@ -1,3 +1,4 @@
+import module from 'node:module';
 import { serve } from '@hono/node-server';
 import { Hono } from 'hono';
 import { compress } from 'hono/compress';
@@ -22,14 +23,20 @@ const isTinypoolWorker = (): boolean => {
   return tinypoolState?.isTinypoolWorker ?? false;
 };
 
-// Skip server initialization if running as a Tinypool worker
-if (!isTinypoolWorker()) {
+// Check if running in warmup mode (for compile cache generation)
+const isWarmupMode = (): boolean => {
+  return process.env.WARMUP_MODE === 'true';
+};
+
+// Skip server initialization if running as a Tinypool worker or in warmup mode
+if (!isTinypoolWorker() && !isWarmupMode()) {
   const API_TIMEOUT_MS = 35_000;
 
   // Log server metrics on startup
   logInfo('Server starting', {
     metrics: {
       processConcurrency: getProcessConcurrency(),
+      compileCacheDir: module.getCompileCacheDir(),
     },
   });
 

website/server/warmup.mjs

@@ -0,0 +1,29 @@
+/**
+ * Warmup script for Node.js compile cache generation.
+ *
+ * This script is executed during Docker build to pre-generate V8 compile cache.
+ * By loading all modules at build time, subsequent cold starts will use
+ * the cached compiled code, reducing startup latency.
+ *
+ * @see https://nodejs.org/api/module.html#moduleenablecompilecachedir
+ */
+
+import { enableCompileCache, flushCompileCache } from 'node:module';
+
+// Enable compile cache (uses NODE_COMPILE_CACHE env var for directory)
+enableCompileCache();
+
+// Set warmup mode to prevent server from actually starting
+process.env.WARMUP_MODE = 'true';
+
+// Import the server module to trigger compilation of all dependencies
+await import('./dist-bundled/server.mjs');
+
+// Flush cache to disk immediately (default is on process exit)
+flushCompileCache();
+
+console.log('Compile cache generated successfully');
+
+// Explicitly exit the process
+// Some modules (like winston/logging) may keep the event loop alive
+process.exit(0);