Senior Full Stack Developer to Fix and Stabilize Vibe-Coded SaaS Application

We are looking for an experienced Full Stack Developer to review, stabilize, and improve an existing AI-generated (vibe-coded) web application. The app is based on Replit. The application is functional but has accumulated technical debt, inconsistent architecture, and quality issues that need to be addressed before further development. Responsibilities Review the existing codebase and architecture Identify bugs, security vulnerabilities, and performance bottlenecks Refactor AI-generated code into clean, maintainable, production-ready code Improve scalability, code organization, and overall application quality Fix existing issues while minimizing regressions Provide recommendations for future development Collaborate with our team on implementation priorities Requirements 5+ years of experience in full-stack development Strong experience with Python, Node.js, React, Next.js, or similar modern frameworks Excellent debugging and production troubleshooting skills Experience reviewing and refactoring existing codebases Strong understanding of API design, databases, authentication, and deployment Experience working with AI coding tools such as Cursor, Claude Code, GitHub Copilot, or Replit is a plus Ability to quickly understand unfamiliar codebases Excellent written and spoken English Nice to Have Experience rescuing AI-generated or rapidly prototyped applications Experience with SaaS platforms and multi-tenant architectures Experience with AWS, Docker, CI/CD, PostgreSQL, Redis, or Supabase When Applying Please include: A brief description of a project where you inherited an existing codebase and significantly improved it The AI coding tools you regularly use Your availability over the next two weeks Your hourly rate