My real goal with #100 was to enable shipping free-threaded wheels. I'm actively working on improving the state of free-threaded support for popular packages on PyPI and this package is one of them. I'll be linking to this issue from https://py-free-threading.github.io/tracking/. See that website for lots more information on supporting free-threaded Python.

Looking at the existing tests, they don't use the python threading module at all and there aren't any rust-level tests. Is that correct?

One thing we could try without writing tests for explicit multithreaded use is running pytest-run-parallel on the full test suite. That wouldn't catch thread safety issues caused by sharing data structures provided by rpds between threads, but it would catch issues due to use of global state.

I see this library already uses new_sync to create the rpds data structures, so according to the rpds docs everything should be thread safe. Do you agree with that assessment?

But also I don't actually see any multithreaded tests in the rust rpds library itself, so I'm not sure how carefully validated that is besides the fact that cargo parallelizes tests automatically.

Do you have any ideas for ways to validate the thread safety of the python library before we upload wheels and declare the rpds module is thread-safe?