Ruff
Ruff is a very fast Python linter and formatter that checks and fixes code style.
Ruff is a tool that helps programmers write cleaner and more consistent Python code. It automatically checks code for style errors, like incorrect spacing or naming conventions, and can often fix them automatically.
Think of it like a spell checker for your code. Just like a spell checker catches typos, Ruff catches common coding mistakes and suggests or applies corrections, making the code easier for humans and machines to read.
Ruff is an extremely fast linter and formatter for Python, written in Rust. It aims to replace multiple existing tools like Flake8, isort, and Black by integrating their functionality into a single, high-performance binary. Its speed comes from its Rust implementation and efficient parsing of Python code.
Ruff supports a wide range of checks and can automatically fix many style violations. It is highly configurable, allowing developers to tailor its behavior to project-specific needs and coding standards.
Ruff is appearing in frontier AI news because it is a critical tool for managing the complex codebases developed by AI labs. OpenAI's acquisition of Astral, which develops Ruff, highlights its importance in streamlining development workflows for large-scale AI projects.
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- OpenAI to acquire AstralOpenAI · OpenAI News ·
- OpenAI ChatGPT
- OpenAI acquired Astral, the company behind Ruff, integrating its popular open-source Python developer tools into its ecosystem.
- Flake8
- An older, slower Python linter that Ruff aims to replace.
- Black
- A popular Python code formatter that Ruff also integrates.
- isort
- A tool for sorting Python imports that Ruff also handles.
Ruff was developed by Astral, a company focused on developer tools. It is written in Rust to achieve high performance. Source ↗
If you have Python code, you can install Ruff using pip. Then, run `ruff check your_file.py` to see if it finds any style issues. To automatically fix some issues, run `ruff check --fix your_file.py`.
The Playbook: reusable how-tos, prompts, configs and tips pulled out of the news.
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Questions people ask
- Is Ruff a programming language?
- No, Ruff is a tool for the Python programming language. It checks and formats Python code.
- Why is Ruff so fast?
- Ruff is written in the Rust programming language, which is known for its speed and efficiency. It also uses optimized algorithms for code analysis.
First seen on Subvolts Mar 19, 2026. Updated Sep 14, 2026. Written by an AI model from the items above and reviewed against them weekly; report an error.