astral-sh/uv

uv is a tool that handles everything to do with running Python projects: installing the Python language itself, creating isolated environments, fetching the libraries a project depends on, locking those library versions so the project builds the same way later, and running the resulting code. The pitch is that it bundles into one command-line program what would normally be a stack of separate tools, and that it runs ten to a hundred times faster than the older standard, pip, because it is written in Rust rather than Python. Under the hood, uv is a dependency resolver: given a list of libraries a project wants, it figures out a set of exact versions that satisfy everyone's requirements, records that decision in a lockfile, and then downloads and links the libraries from a shared cache on disk so the same library is never stored twice. It also installs Python versions on demand, supports a pip-style interface so existing projects can switch without changing their workflow, and supports workspaces where several related projects sit in one repository. Single-file scripts can declare their own dependencies in a comment block and uv will fetch them on the fly. It runs on macOS, Linux, and Windows. Someone would reach for uv when they are tired of waiting on pip, juggling pyenv plus virtualenv plus pipx, or trying to make sure two machines install exactly the same versions of everything. It is backed by Astral, the team behind the Ruff linter. The full README is longer than what was provided.