126 million downloads per month. That's how big uv, Astral's Python package manager, has gotten since launching in February 2024. Now OpenAI is buying the whole company.
Astral, the startup behind some of the most widely used Python developer tools in the world, has agreed to join OpenAI as part of its Codex team. Financial terms were not disclosed. The deal is subject to regulatory approval.
For anyone who writes Python, you've probably already used Astral's tools. Ruff is a linter and code formatter written in Rust that's become the default choice for Python projects. Uv handles dependency management and environment setup. Ty, announced in December 2025, is a fast type checker designed to replace mypy and Pyright. Together, these tools cover linting, formatting, package management, and type checking - basically the entire Python development workflow outside of writing the code itself.
Codex Gets a Foundation Layer
The strategic logic is straightforward. OpenAI's Codex, its AI coding agent, has hit 2 million weekly active users with 3x user growth and 5x usage increase since January. But generating code is only part of the job. A real coding agent needs to manage dependencies, run linters, verify types, and maintain clean codebases. Astral's tools are exactly that infrastructure.
By owning the tools that format, lint, and type-check Python code, OpenAI can tightly integrate them into Codex's workflow. Instead of generating code and hoping the developer's local tooling catches issues, Codex could run ruff and ty as part of its own verification loop.
This follows a pattern. Anthropic acquired Bun, the JavaScript runtime, in December 2025. AI companies are realizing that owning developer infrastructure gives their coding agents a structural advantage.
The Open-Source Question
Astral CEO Charlie Marsh said in the announcement: "Open source is at the heart of that impact...we'll keep building in the open, alongside our community." OpenAI echoed the commitment to supporting Astral's open-source products after closing.
The community response has been cautiously optimistic but wary. All of Astral's tools use permissive open-source licenses, which means they can be forked if OpenAI changes direction. Astral engineer Douglas Creager pointed out that "worst-case scenarios have the shape of 'fork and move on.'" That's reassuring, but forking a project of uv's scale is a massive community undertaking that nobody wants to actually do.
One notable absence from both announcements: pyx, Astral's private PyPI registry that launched in beta in August 2025. Whether that product continues, gets folded into Codex, or quietly disappears is an open question.
The bigger concern is competitive. If OpenAI owns the most popular Python package manager, could they optimize it for Codex in ways that subtly disadvantage competing AI coding tools? The permissive license limits how far they could take this, but the incentive structure is worth watching.
For Python developers, the immediate impact is likely positive. Astral's tools get the backing of one of the best-funded companies in tech, and the team stays focused on developer tooling. The long-term question is whether "open source at heart" survives contact with OpenAI's competitive pressures.