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AI refactoring

Turning AI-generated code into production

A startup had a working AI prototype – but it was not production-ready: no authentication, no tests, no deployment, open security gaps. Within 4 weeks it became an application serving real users.

Duration4 weeks
ModelFixed price
RoleFreelancer
Resultlive with real users

The problem

The prototype had been built quickly with AI support and looked impressive in the demo – but the foundations for production were completely missing: users could not log in securely, some data lived in the browser, there were no tests and no automated deployment. All of that had to be solved before the first real user.

The solution

First I fully understood the existing code (reverse engineering), then made it production-ready step by step: real authentication, clean data storage, tests, CI/CD and closed security gaps. The prototype was not thrown away – it was built out.

Step-by-step approach

  • Code analysisFully understood the inherited AI code, documented data flows and vulnerabilities.
  • Authentication & rolesReal user management with JWT auth and role-based permissions instead of a demo login.
  • TestsUnit and integration tests for critical paths – including error and edge cases.
  • CI/CD pipelineAutomated builds, tests and deployment steps so releases are no longer manual work.
  • Security hardeningInput validation, secure password storage and closing typical vulnerabilities.
React Node.js JWT auth PostgreSQL CI/CD

The result

The prototype now runs in production – with real users, real data and no outages. Instead of rebuilding from scratch, the existing state was rescued and completed with everything needed for operations. The team can now keep developing on its own because tests and pipeline are in place.

4 wksfrom prototype to production
100 %of critical paths covered by tests
0known security gaps left open
In one sentence: AI speeds up the first draft – but production readiness is manual work. That is exactly the gap I close.

Who this approach is for

  • Startups with an AI prototype facing their first real user load
  • Teams where nobody really knows what the generated code does
  • Projects missing auth, roles, tests or deployment
  • Applications that need a security audit before going live
Request a similar project → Service: AI Code Refactoring

Further references

Two more projects from related fields.

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Agency subcontractor

PHP monolith → React/Next.js

For an agency, a React/Next.js frontend was built in front of an existing PHP API in 5 weeks – without rewriting the backend.

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Need your AI prototype in production?

30 minutes of free analysis of your AI code – I will tell you what is missing before production and what it costs.

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🔹 Fixed price. 4 weeks. You keep the code.

Portrait of Joerg Loos, freelance full-stack developer for legacy modernization and AI integration
About me

Your technical sparring partner for difficult software projects

I specialize in making AI-generated prototypes production-ready – from a quick experiment to a stable, secure application with architecture, tests and deployment.

Stack: React, Node.js, Python, Java • Approach: pragmatic, transparent, production-focused.