Common React Deployment Mistakes That Break Production

Common React Deployment Mistakes That Break Production

Apps that work locally sometimes break in production due to deployment mistakes. Here are the common ones and how to avoid them.

Broken Deep Links

Client-side routes return 404 in production because the host serves 404 for routes that are not files. Configure the host to redirect all routes to index.html.

Wrong Environment Variables

Forgetting to set production environment variables in the hosting dashboard means the app calls the wrong API or has no API key. Set them before deploying.

Unauthorized Auth Domains

Auth providers only allow authorized domains. Forgetting to add your deployed domain means auth redirects fail, even though they work on localhost.

Large Bundle Size

Shipping the entire app in one bundle makes the first load slow. Lazy-load heavy routes with React.lazy to keep the initial bundle small.

Hardcoded Localhost URLs

Calling http://localhost:5000 in production obviously fails. Use environment variables for API URLs so the app calls the right backend per environment.

No Error Boundary

An unhandled error in production shows a blank screen. Add an error boundary so users see a fallback instead of a white page.

Not Testing the Deployed App

Assuming the deploy worked without testing. Click through the deployed app, test auth, forms, and API calls to catch issues that only appear in production.

The Takeaway

Common deployment mistakes include broken deep links, wrong env vars, unauthorized auth domains, large bundles, hardcoded localhost URLs, no error boundary, and not testing the deployed app. Catch these before users do.