Move Vercel entry point to root api/index.py (Vercel Python convention)

api/index.py

@@ -0,0 +1,31 @@
+"""
+Vercel serverless entry point for Civic City Hub backend.
+
+Vercel Python serverless functions use WSGI. FastAPI is ASGI, so we use
+Mangum — an ASGI-to-WSGI adapter — to bridge the gap.
+
+Vercel looks for `app` (WSGI callable) in api/index.py at the project root.
+"""
+import os
+import sys
+from pathlib import Path
+
+# Signal to storage.py that we're on Vercel (use /tmp for SQLite)
+os.environ["VERCEL"] = "1"
+
+# Ensure the backend root is on sys.path so all imports resolve
+_backend_root = Path(__file__).parent / "backend"
+if str(_backend_root) not in sys.path:
+    sys.path.insert(0, str(_backend_root))
+
+# Change working directory to backend root so relative paths work
+os.chdir(str(_backend_root))
+
+# Import the FastAPI app
+from api.server import app as fastapi_app
+
+# Wrap with Mangum for Vercel WSGI compatibility
+from mangum import Mangum
+
+# Vercel Python runtime looks for 'app' (WSGI callable)
+app = Mangum(fastapi_app, lifespan="off")

requirements.txt

@@ -0,0 +1,8 @@
+# Vercel Python runtime requirements
+# These are installed when the api/index.py serverless function is built
+fastapi>=0.110.0
+uvicorn[standard]>=0.27.0
+openai>=1.12.0
+cryptography>=41.0.0
+httpx>=0.27.0
+mangum>=0.17.0

vercel.json

@@ -5,13 +5,21 @@
       "use": "@vercel/next"
     },
     {
-      "src": "backend/api/**/*.py",
-      "use": "@vercel/python"
+      "src": "api/index.py",
+      "use": "@vercel/python",
+      "config": {
+        "functions": {
+          "api/index.py": {
+            "runtime": "python3.12@latest",
+            "maxDuration": 30
+          }
+        }
+      }
     }
   ],
   "routes": [
-    { "src": "/health", "dest": "backend/api/index.py" },
-    { "src": "/api/(.*)", "dest": "backend/api/index.py" },
+    { "src": "/health", "dest": "api/index.py" },
+    { "src": "/api/(.*)", "dest": "api/index.py" },
     { "handle": "filesystem" },
     { "src": "/(.*)", "dest": "frontend/$1" }
   ]