Astral vs tox

Astral makes open-source tools for Python development, including Ruff, a linter, and uv, a package and project manager. Both are written in Rust. uv brings together project management, a universal lockfile, script execution, Python version management, tool installation, workspaces and a pip-compatible interface. Astral describes that interface as providing a 10–100x speedup over pip. uv supports macOS, Linux and Windows. Its documented integrations include Docker, Jupyter, marimo, GitHub Actions, GitLab CI/CD, pre-commit, PyTorch, FastAPI, Bazel, artifact registries, Renovate, Dependabot, AWS Lambda and Coiled. Astral says its tools are permissively licensed and free forever. It describes security controls for workflows and releases, including read-only default workflow permissions, full-length commit-SHA pinning, Trusted Publishing, Sigstore attestations and immutable GitHub releases. Documentation directs users to its Discord community for support. The separate pyx package registry offers optimized installs and other package-management features, but is no longer accepting new signups. Astral has announced an agreement to join OpenAI as part of the Codex team.

tox is a free, open-source command-line tool for creating virtual environments, checking package builds and installations across different environments, and running tests in them. It can orchestrate test runners, linters, formatters, documentation generators, and build or publishing tools. As a continuous-integration frontend, tox combines CI workflows with shell-based testing and reduces boilerplate. Configuration can be stored in tox.toml, tox.ini, pyproject.toml, or toxfile.py. By default, it removes host environment variables unless allowed through pass_env and adjusts PATH so commands use the active environment. The command-line tool requires Python 3.10 or higher. Installation guidance covers pipx, uv, and pip, with apt and brew package-manager routes also documented. Plugins include tox-gh-actions for GitHub Actions, tox-uv for faster package installation, and tox-gh for enhanced GitHub integration. It runs on Linux, macOS, and Windows and is maintained as a volunteer open-source project.