Pants 2.5.0.dev2 is released: https://pypi.org/project/pantsbuild.pants/2.5.0.dev2/ This is the first release to support running Pants with Python 3.9. To use Py39, please update your ./pants script by using the version at https://raw.githubusercontent.com/pantsbuild/setup/9ba1dbf20e141ddc92443c782afd9c3ed5ebb7f2/pants.