Fix?

backend/src/index.js

@@ -17,6 +17,7 @@ if (process.env.NODE_ENV) {
 const app = express();
 const httpServer = createServer(app);
 const io = new Server(httpServer, {
+  path: '/api/socket.io',
   cors: {
     origin: true,
     credentials: true,

frontend/app/composables/useApi.ts

@@ -1,9 +1,13 @@
 // composables/useApi.js
 import { ref } from 'vue'
 
+function normalizeUrl(url: string): string {
+  return url.replace(/\/+$/, '')
+}
+
 export default function useApi() {
   const config = useRuntimeConfig()
-  const baseUrl = config.public.apiBaseUrl
+  const baseUrl = `${normalizeUrl(config.public.apiBaseUrl)}/api`
 
   // Generic GET request
   const get = async (endpoint) => {

frontend/app/composables/useSocket.ts

@@ -1,9 +1,13 @@
 import { ref, onUnmounted } from 'vue'
 import { io } from 'socket.io-client'
 
+function normalizeUrl(url: string): string {
+  return url.replace(/\/+$/, '')
+}
+
 export default function useSocket() {
   const config = useRuntimeConfig()
-  const socketUrl = `${config.public.apiBaseUrl.replace('/api', '')}`
+  const apiBaseUrl = normalizeUrl(config.public.apiBaseUrl)
 
   const socket = ref(null)
   const isConnected = ref(false)
@@ -11,7 +15,8 @@ export default function useSocket() {
   function initSocket() {
     if (socket.value) return
 
-    const s = io(socketUrl, {
+    const s = io(apiBaseUrl, {
+      path: '/api/socket.io',
       transports: ['websocket', 'polling'],
       reconnection: true,
       reconnectionAttempts: 10,

frontend/nuxt.config.ts

@@ -13,7 +13,7 @@ export default defineNuxtConfig({
 
   runtimeConfig: {
     public: {
-      apiBaseUrl: process.env.API_BASE_URL || 'http://localhost:5000/api'
+      apiBaseUrl: process.env.API_BASE_URL || 'http://localhost:5000'
     }
   },