diff --git a/src/server/api/apps.ts b/src/server/api/apps.ts
index 6a3bdf8..51308bc 100644
--- a/src/server/api/apps.ts
+++ b/src/server/api/apps.ts
@@ -229,7 +229,7 @@ router.post('/:app/rename', async c => {
 
   if (!newName) return c.json({ ok: false, error: 'New name is required' }, 400)
 
-  const result = renameApp(appName, newName)
+  const result = await renameApp(appName, newName)
   if (!result.ok) return c.json(result, 400)
 
   return c.json({ ok: true, name: newName })
diff --git a/src/server/apps.ts b/src/server/apps.ts
index b8096ee..95cb936 100644
--- a/src/server/apps.ts
+++ b/src/server/apps.ts
@@ -142,7 +142,7 @@ export function registerApp(dir: string) {
   }
 }
 
-export function renameApp(oldName: string, newName: string): { ok: boolean, error?: string } {
+export async function renameApp(oldName: string, newName: string): Promise<{ ok: boolean, error?: string }> {
   const app = _apps.get(oldName)
   if (!app) return { ok: false, error: 'App not found' }
 
@@ -155,15 +155,13 @@ export function renameApp(oldName: string, newName: string): { ok: boolean, erro
   const oldPath = join(APPS_DIR, oldName)
   const newPath = join(APPS_DIR, newName)
 
-  // Stop the app if running
+  // Stop the app and wait for process to fully exit so the port is freed
   const wasRunning = app.state === 'running'
   if (wasRunning) {
+    const proc = app.proc
     clearTimers(app)
     app.proc?.kill()
-    app.proc = undefined
-    if (app.port) releasePort(app.port)
-    app.port = undefined
-    app.started = undefined
+    if (proc) await proc.exited
   }
 
   try {
@@ -681,6 +679,10 @@ async function runApp(dir: string, port: number) {
 
   // Handle process exit
   proc.exited.then(code => {
+    // If the app has moved on (e.g. renamed and restarted), this is a
+    // stale exit handler — don't touch current app state or ports
+    if (app.proc && app.proc !== proc) return
+
     // Clear all timers
     clearTimers(app)