App Crashes Immediately After Deploy on Replit
Your app builds successfully but crashes immediately after deployment starts. The app container exits with an error before becoming healthy.
This typically indicates environment configuration issues, missing dependencies, or startup errors.
Error Messages You Might See
Common Causes
- Missing environment variables (API keys, database URL)
- Port not available or already in use
- Database migrations failing during startup
- Memory limit exceeded during startup
- Missing required files or resources
How to Fix It
Check Replit deployment logs for actual error messages. Verify all required environment variables are set in Replit Secrets. Ensure your app listens on the PORT environment variable (usually 8080). Run migrations before app startup. Test locally in Replit shell before deploying.
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Get HelpFrequently Asked Questions
Where do I see deployment logs?
Click 'Logs' in the Replit deployment panel to view startup errors
What port should my app use?
Listen on the PORT environment variable, which Replit sets to 8080