In order to allow for rapid, predictable releases, Setuptools uses a mechanical technique for releases, enacted on tagged commits by continuous integration.
To finalize a release, run
tox -e finalize, review, then push
If tests pass, the release will be uploaded to PyPI.
Some have asked why Setuptools is released so frequently. Because Setuptools uses a mechanical release process, it’s very easy to make releases whenever the code is stable (tests are passing). As a result, the philosophy is to release early and often.
While some find the frequent releases somewhat surprising, they only empower the user. Although releases are made frequently, users can choose the frequency at which they use those releases. If instead Setuptools contributions were only released in batches, the user would be constrained to only use Setuptools when those official releases were made. With frequent releases, the user can govern exactly how often he wishes to update.
Frequent releases also then obviate the need for dev or beta releases in most cases. Because releases are made early and often, bugs are discovered and corrected quickly, in many cases before other users have yet to encounter them.
Additionally, anyone with push access to the master branch has access to cut releases.