AI-Powered Document API (RAG) — deployed on Render FastAPI, PostgreSQL, OpenAI API, React, Docker, GitHub Actions • Built a RAG backend: PDF ingestion, overlapping chunking, embedding-based retrieval, and OpenAI answers grounded in retrieved chunks, behind JWT auth with response caching. • Debugged a chain of Render build and runtime failures (memory limits, dependency conflicts, ephemeral disk) and replaced a local FAISS index with PostgreSQL-stored embeddings and NumPy cosine similarity.