diff --git a/apps/api/src/index.ts b/apps/api/src/index.ts
index 3d101d1..fb791a1 100644
--- a/apps/api/src/index.ts
+++ b/apps/api/src/index.ts
@@ -66,8 +66,13 @@ startBrokerPoller()
 // Drain the D-05 outbox every 15s: dispatches pending CalDAV writes to Fastmail
 startOutboxWorker()
 
-// Serve React PWA static assets from ./public (Vite build output)
-app.use('/assets/*', serveStatic({ root: './public' }))
+// Serve React PWA static assets from ./public (Vite build output).
+// MUST serve the whole ./public tree, not just /assets/* — root-level PWA files
+// (manifest.webmanifest, sw.js, registerSW.js, workbox-*.js, icon-*.png,
+// apple-touch-icon.png) live at the root. serveStatic calls next() when a file
+// is not found, so SPA routes fall through to the index.html catch-all below.
+// (Registered AFTER /health, /api/*, and /callback, so those win.)
+app.use('/*', serveStatic({ root: './public' }))
 app.get('*', serveStatic({ path: './public/index.html' }))
 
 // Only start the HTTP server when this module is run directly (not imported in tests)