Astral's Charlie Marsh had Codex build serc, a Rust CPython bytecode compiler

Charlie Marsh of Astral, the company behind uv, said he had OpenAI's Codex build serc, a CPython bytecode compiler written in Rust. By his account it produces byte-for-byte identical output to CPython's own compiler on the top 10,000 PyPI packages and runs 2-4x faster.

Marsh called it entirely an experiment, though Astral may ship it, opt-in, in uv. In a follow-up he said it is published on crates.io (serc-cli) and PyPI (uvx serc) and lives in the astral-experiments organization. The speed and output-match figures are his own claims. The post had about 525 likes by November 9.