AI SaaS Model Audit & Fixes

We have an existing AI-powered SaaS platform that is already substantially developed and approaching production release. Before launch, we have encountered several technical issues and would like an experienced AI / Full Stack Engineer to review the current system, identify the root causes, fix the critical problems, and help ensure the platform is stable and ready for production. This is not a project starting from scratch. The main application, backend, database, and AI integrations already exist. We need someone who is comfortable joining an existing codebase, understanding the architecture quickly, debugging complex issues, and making production-quality fixes. Main Responsibilities Review the current application architecture and implementation Analyze existing AI / OpenAI API integrations Identify bugs, integration issues, and potential bottlenecks Fix critical backend and frontend problems Review API communication and error handling Review prompt handling and AI response flows Check conversation/session handling where applicable Review database interactions and data consistency Check token/API usage handling and related limits Improve reliability of external API integrations Review logs and diagnose intermittent errors Identify security or production-readiness concerns Test important workflows before release Recommend any urgent improvements required for launch Preferred Experience Strong experience with several of the following: OpenAI API / LLM integrations AI agents and AI-powered SaaS products Node.js / TypeScript Python React / Next.js REST APIs PostgreSQL / MongoDB Webhooks and third-party integrations Docker AWS / Vercel or similar cloud infrastructure Authentication and authorization Debugging production systems SaaS architecture API security and application security Experience reviewing or rescuing an existing project close to launch is highly preferred. What We Are Looking For We are looking for someone who can analyze first, then fix, rather than immediately rewriting the system. The ideal developer should be able to: Understand an unfamiliar codebase quickly Reproduce the current problems Identify the actual root causes Explain which issues are critical for launch Implement clean and safe fixes Test the affected workflows Help us get the platform production-ready as soon as possible Current Status The platform is already built and we are preparing for release. Several issues have appeared during final testing, so this work is currently a high priority. We can provide the selected developer with the relevant source code, technical information, current issues, logs, and access required for investigation. When Applying Please briefly tell us: Your experience with OpenAI / LLM-based SaaS platforms Your experience debugging existing production or pre-production applications Your strongest backend stack Whether you have experience with React / Next.js, Node.js, and Python Examples of similar debugging, AI integration, or SaaS stabilization work How you normally approach an unfamiliar codebase with urgent production issues Please avoid generic proposals. We are mainly interested in developers who can review an existing system deeply and solve problems efficiently. Potential for additional development work after the initial review and launch fixes if the collaboration goes well. Budget: USD 15–25