Senior Full Stack Engineer – AI Audio Stem Separation Platform

We’re building a high-performance AI audio platform focused on studio-quality stem separation and intelligent enhancement. We already have a strong, working POC using FastAPI + HT-Demucs and now need a solid backend engineer to help turn it into a production-ready MVP. This is hands-on work building the core systems that power uploads, heavy ML job processing, user projects, and reliable delivery of enhanced audio stems. What You’ll Work On Productionize and scale our existing FastAPI backend. Implement authentication, project & user management, and async job processing (queuing + status tracking). Create the integration layer that connects the web app to our core audio processing engine. Build out database models, file/storage handling (S3), and subscription/billing flows with Stripe. Add proper error handling, logging, monitoring, and observability so everything runs reliably at scale. Help design a clean, maintainable architecture that can grow beyond the MVP. Requirements Strong experience with FastAPI (Python) and async task queues (Celery, RQ, or similar). Solid PostgreSQL skills and comfort with ORMs. Experience handling ML/audio pipelines, large file processing, and cloud storage. Production-first mindset — you care about reliability, performance, and clean code. Familiarity with Stripe integration is a plus. Nice-to-Haves Hands-on work with Demucs, torchaudio, Pedalboard, or similar audio/ML tools. Docker, cloud deployment (AWS/GCP), and infrastructure knowledge.