Hacker News AIT2·Models
78 pts
A research team used Opus 5.5 agents to translate CPython 3.15.2 internals line by line into 613,318 lines of Lean, tested each piece against real Python, machine-checked every proof, and surfaced 418 bug reports in CPython along the way. The result is a machine-verifiable formal model of CPython that offers a new engineering paradigm for interpreter semantic correctness.