Summary

Recently, rustpython-parser has definitely a lot more users than RustPython itself.
I suggest splitting parser out from RustPython repository.

Detailed Explanation

When upstream is comparably smaller than downstream, downstream goes to make fragmentation rather than contributing to upstream.

The problem here is the user expectation and the project structure has opposite ratio.

In the project RustPython, parser is comparably small module - mostly due to huge stdlib of Python.
For rustpython-parser users, only rustpyhon-parser is useful but other parts is useless burden.

I'd like to suggest splitting parser out from RustPython repository.
it will be one of the good way to keep rust-implemented python parser in single repository with minimum fragmentation.

Drawbacks, Rationale, and Alternatives

RustPython will use the separated parser with git tag. It will increase cost of maintenance of other parts of RustPython.

Unresolved Questions

Not to restrict the parser's potent to just RustPython, the name even can be something different. python-parser or python3-parser.