I will fix nodejs express API bugs 500 errors, routes, middleware, auth

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beatrice_efron
Beatrice

About this gig

Are you getting 500 errors, broken routes, failing middleware, or authentication issues in your Node.js/Express API?

I will debug and fix your backend professionally, explain what caused the issue, and apply clean fixes that keep your API stable.


What I can help you fix

  • 500/400 errors, server crashes, unhandled promise rejections
  • Broken routes/controllers/middleware
  • JWT auth issues (tokens, roles, refresh token logic)
  • CORS, cookies, sessions, headers
  • MongoDB/Mongoose problems (schema, queries, populate, validation)
  • API response issues, validation errors, status codes
  • Environment/config issues (.env, ports, production vs local)
  • Deployment-related API issues (common Express runtime problems)


What you'll get

  • The bug(s) fixed in your codebase
  • Clear notes on what was wrong + what I changed
  • Basic guidance to prevent it happening again


If you're not sure whats wrong, message me with the error and Ill tell you the best package.

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Get to know Beatrice

Beatrice

Website Developer

  • FromUnited Kingdom
  • Member sinceApr 2026
  • Avg. response time1 hour
  • Languages

    English
I am a dedicated and results-driven website developer with a passion for creating responsive, user-friendly, and visually engaging digital experiences. I specialize in building modern websites that combine clean design with efficient functionality, ensuring both performance and usability. With a strong foundation in front-end and back-end development, I work with technologies such as HTML, CSS, JavaScript, and various frameworks to deliver scalable and maintainable solutions. I enjoy transforming ideas into fully functional websites, whether it’s a simple landing page or a complex one