So there's a few things here: • Building

mypy.pex

finished (probably quickly)

Completed: Building mypy.pex from build-support/mypy_lockfile.txt

• What you're seeing is Pants installing of the dependencies in your resolve. Depending on the size of your resolve, or the size of those deps it can take a while. ◦ This also depends on your settings, which Pants version you're using, and if you're using the new PEX lockfiles • The linked MyPy issue has to do with the performance of running mypy, which you haven't gotten to that step yet 😅