Strange subthread. I don't see Claude Opus 4.6 changing the tide for PyPy. There is no need to understate AI capabilities for this.

"Anthropic released vibe coded C compiler that doesn't work" sounds like https://github.com/anthropics/claudes-c-compiler/issues/1 passed through a game of telephone. The compiler has some wrong defaults that prevent it from straightforwardly building a "Hello, world!" like GCC and Clang. The compiler works:

> The 100,000-line compiler can build a bootable Linux 6.9 on x86, ARM, and RISC-V. It can also compile QEMU, FFmpeg, SQlite, postgres, redis, and has a 99% pass rate on most compiler test suites including the GCC torture test suite. It also passes the developer's ultimate litmus test: it can compile and run Doom.

https://www.anthropic.com/engineering/building-c-compiler

Prompts for this?

The primary objective is to retarget PyPy on top of the Python main branch. A minor objective is to document what of PyPy can be ported to CPython (or RustPython).

Keep a markdown log of issues in order to cluster and close when fixed

Clone PyPy and CPython.

Review the PyPy codebase and docs.

Prepare a devcontainer.json for PyPy to more safely contain coding LLMs and simplify development

Review the backlog of PyPy issues.

Review the CPython whatsnew docs for each version of python (since and including 3.11).

What has changed in CPython since 3.11 which affects PyPy?

Study the differences between PyPy code and CPython code to understand how to optimize like PyPy.

Prepare an AGENTS.md for PyPy.

Prepare an agent skill for upgrading PyPy with these and other methods.

Write tests to verify that everything in PyPy works after updating it to be compatible with the Python main branch (or the latest stable release, CPython 3.14)

Strikes me as the worst possible solution if they're struggling to find maintainers in the first place. Who reviews the vibe coded patches?

> Anthropic released vibe coded C compiler that doesn't work, how their LLM can help in maintaining PyPy?

This is the perfect question to highlight the major players. In my opinion, a rapidly developing language with a clear reference implementation, readily accessible specifications, and a vast number of easily runnable tests would make an ideal benchmark.