Example repo showing a bug in Maturin (I think)
This repo uses a directory of stub files to define type hints for a package instead of a single file. You can see types-requests for an example of this layout.
I haven't written the Rust code to make this example a package because it's irrelevant.
If you run maturin develop in this repo it fails with Found a directory with the module name (solders) next to Cargo.toml, which indicates a mixed python/rust project, but the directory didn't contain an __init__.py file.