BART

Bay Area Rapid Transit runs on production codebases that outlive their documentation. I built a secure, fully local code intelligence platform that generates architecture documentation and diagrams for 20,000+ line codebases in under two minutes. It combines static analysis, code graphs, and grounded LLMs. A modular Tree-Sitter/AST parsing framework supports 8+ languages, and a multi-stage validation pipeline keeps the LLM honest: 97.5% summary accuracy, with everything staying on BART’s own machines.