Cargo is my ideal, but really anything that doesn't make me manage virtualenvs or take 30 minutes to resolve dependencies. Note that "managing my own virtualenvs" is tricky because you have to make sure everyone has all of the same versions of the same dependencies in their virtualenv across your entire team (including production). I'm sure there are workflows that allow for this (probably with some tradeoffs), but we haven't figured it out. For a while we used Docker, but performance degraded exponentially as our test base grew (Docker for Mac filesystem problems, probably). Eventually we settled on pantsbuild.org which has a lot of problems, is super buggy, no one can figure out its plugin architecture, etc but as long as you stay on the happy path it generally works okay which puts it in one of the ballparks between any other Python dependency management scheme I've tried and Go/Rust/etc package management.