Daniel M.

I build and maintain SaaS applications, backend APIs, and AI-powered features using NestJS, React, TypeScript, Python, and PostgreSQL. With 3,500+ hours billed on Upwork, $20K+ earned, and a 100% Job Success Score, I bring experience supporting production systems through long-term client relationships. My two largest completed contracts involved NestJS backend development, both earning five-star ratings. I can help you: • Build and extend web applications and SaaS platforms • Develop APIs, third-party integrations, and real-time features • Diagnose backend bugs and improve application reliability • Integrate LLMs, RAG, and agentic workflows into existing products • Maintain databases, deployment workflows, and monitoring I take ownership from requirements through implementation and testing, communicate progress clearly, and document my work for straightforward handover. Share your current application, technical challenge, and priorities, and we can discuss a practical next step.