Hi, we're trying to debug slow lockfile generation performance (5-10 mins in some instances), and are wondering how to get some more information about the dependency resolution process; we hit a significant slowdown when using dependencies pulled in from a git repo pinned to a particular commit, and attempts to make the logging more verbose don't seem to propagate correctly. Any pointers here?

One thing to do is set

--keep-sandboxes=always

and find the sandbox that ran the lockfile generation (the paths are logged to the console). In that sandbox is a

__run.sh

file containing a pex command. That allows you to reproduce the problem directly in pex, outside of pants.

Will note that switching to

uv_requirements

didn't help

This macro doesn't use uv in the background, it just allows reading in requirements from the uv section of

pyproject.toml

. That's why it didn't run any faster for you than before, as pip is still doing the resolution in the background

Ah got it - are there any plans to support

uv

for the lockfile generation/resolution itself?

There’s an open ticket for that, but there are no active plans at the moment. It’s actually more complicated than it might seem - to be a true drop-in replacement for pip in all the cases pex supports, uv would require features it doesn’t (yet?) have. It might be possible to use uv in just the cases that it does support, but that would be delicate.