Hello Render Team,
I am experiencing a persistent CORS issue with my decoupled application and I believe the problem might be in the platform’s environment.
- My Frontend (Netlify):
https://movilwin.com - My Backend Web Service (Render):
https://movilwin-api.onrender.com
My frontend at movilwin.com is making a fetch request to my backend, but it’s being blocked by a CORS policy because the Access-Control-Allow-Origin header is missing from the response.
To debug this, I have deployed a minimal Express.js test server to rule out any issues in my application code. This server does nothing but respond to a /test-cors route with hardcoded CORS headers allowing my frontend’s origin.
- You can see the minimal server code here: [Pega aquí el enlace a tu archivo
server.jsen GitHub] - You can reproduce the error by:
- Going to
https://movilwin.com - Opening the developer console.
- Running this command:
fetch('https://movilwin-api.onrender.com/test-cors')
- Going to
Even with this minimal setup, the browser still reports that the Access-Control-Allow-Origin header is not present. This strongly suggests the header is being stripped or blocked after it leaves my Express application.
Could you please investigate if your reverse proxy or network layer might be affecting the CORS headers for my service?
Thank you for your help.