Bridging Python and Rust: Mitigating GIL Contention in a High-Throughput LLM Gateway When building Aegis , an open-source OpenAI-compatible governance proxy, we made a core architectural decision: use Python (FastAPI/ASGI) for rapid development and API adaptability, but offload high-performance cryptography, Write-Ahead Logging (WAL), and Merkle Mountain Range (MMR) operations to a compiled Rust extension ( aegis_rust_v2 ) via PyO3 and Maturin. However, mixing Python’s asynchronous event loop wi