ast-grep vs Ruff
Which should you use? A side-by-side look at what each one does, who it suits, what it costs, how hard it is to set up, and where each falls short.
Open source · MIT
A command-line tool that searches, lints, and rewrites code by its syntax structure, not plain text.
Open source · MIT
A very fast Python linter and code formatter, written in Rust.
The short answer
Choose ast-grep if you need…
- Developers who want grep-like searching that understands code structure
- Library authors migrating users across breaking API changes
- Tech leads who want to enforce custom code practices with lint rules
- Engineers doing large-scale, consistent code rewrites
Choose Ruff if you need…
- Python developers who want one tool for linting and formatting
- Teams with large Python codebases where slow checks are a problem
- People running checks in a pre-commit hook or editor on save
- Projects that already use pyproject.toml for configuration
Side-by-side
| ast-grep | Ruff | |
|---|---|---|
| Type | CLI | CLI |
| Price | Free and open source | Free and open source |
| Licence | MIT | MIT |
| GitHub stars | 16.4k | 50.4k |
| Setup difficulty | Beginner | Beginner |
| How you get it | Install with a package manager | Install with a package manager |
| Main language | Rust | Rust |
| Last code update | 4 days ago | 4 days ago |
What each one is
ast-grep
ast-grep is a command-line tool that searches code by matching its syntax tree rather than raw text, so a pattern written like ordinary code can find every place that shares the same structure. It can also rewrite matches and run YAML-defined lint rules. People use it to find usages, migrate code across breaking changes, or enforce team coding standards.
Ruff
Ruff checks Python code for style problems and likely bugs, and can automatically format code and fix some errors. It is a single command-line tool that aims to replace several older Python tools such as Flake8, Black, and isort. The README says it is much faster than those tools, and it is installed through pip, uv, or pipx.
Best for
ast-grep
- Developers who want grep-like searching that understands code structure
- Library authors migrating users across breaking API changes
- Tech leads who want to enforce custom code practices with lint rules
- Engineers doing large-scale, consistent code rewrites
Ruff
- Python developers who want one tool for linting and formatting
- Teams with large Python codebases where slow checks are a problem
- People running checks in a pre-commit hook or editor on save
- Projects that already use pyproject.toml for configuration
Strengths
ast-grep
- Patterns look like the code you already write
- Matches by syntax tree, so it ignores formatting differences
- Installable through many package managers including npm, pip, Homebrew, and cargo
Ruff
- The README reports speeds of 10-100x over Flake8 and Black, with testimonials citing larger gains
- Combines linting, formatting, and import sorting behind one interface
- Supports hierarchical configuration for monorepos
Not ideal for
ast-grep
- People who only need simple text search, since plain grep or ripgrep is simpler for that
- Non-programmers, because patterns assume familiarity with code syntax
- Languages not supported by its tree-sitter parsers, which the README does not fully list
Ruff
- Non-Python projects, since it only handles Python code
- People who need to keep using specific Flake8 plugins not covered by its rules (the README says it re-implements many popular ones, not all)
- Users who want a tool with no configuration decisions to learn; it has over 900 rules to choose from
Trade-offs
ast-grep
- Its matching depends on the language grammars it supports, so coverage varies by language
- The README is truncated and does not describe every feature or limitation in detail
Ruff
- Speed figures and testimonials come from the project and its users, not independent benchmarks
- Rule coverage is broad but may not match every plugin or edge case of the tools it replaces
- Version is under 1.0 (0.17.3), so behavior may change between releases
Getting started
ast-grep
Install via npm
npm install --global @ast-grep/cliInstall via pip
pip install ast-grep-cliRuff
Install with uv (recommended)
uv tool install ruff@latestInstall with pip
pip install ruffFrequently asked questions
What is the difference between ast-grep and Ruff?
ast-grep: A command-line tool that searches, lints, and rewrites code by its syntax structure, not plain text. Ruff: A very fast Python linter and code formatter, written in Rust. ast-grep suits developers who want grep-like searching that understands code structure, while Ruff suits python developers who want one tool for linting and formatting.
Are ast-grep and Ruff free?
ast-grep: Free and open source. Ruff: Free and open source.
Is ast-grep or Ruff more popular?
Ruff has more GitHub stars (50.4k) than ast-grep (16.4k). Popularity isn't the same as fit — check which one matches your use case above.
What are other alternatives to ast-grep and Ruff?
Other options people compare them with include jscodeshift, broot, Black.
Keep comparing
Built from our catalogue entries for both products: open-source details come from each project's README (AI-assisted, refreshed weekly) and GitHub data; AI-tool details are editorial. Spotted something wrong? Let us know from either product's page.