Side by side
ast-grep vs Comby
Both stand on code refactoring tools. Which one you can start free with, which one lets you read the code, and what each costs once you pay.
Free plan APIExtensionLinux+3
ast-grep combines structural code search, configurable linting, and rewriting in a free, open-source tool. Its language coverage and integrations are broad, though it does not provide some advanced static-analysis information and rules are limited to one language at a time.
Visit ast-grep
Free plan APILinuxMac+2
Choose Comby for structural code search and refactoring where lightweight syntactic matching is sufficient. Look elsewhere for indentation-sensitive matching or formatting work such as inserting line breaks at a set width.
Visit CombyThe facts
| ast-grep | Comby | |
|---|---|---|
| Free plan | Yes | Yes |
| Open source | Not published | Not published |
| Runs on | API, Extension, Linux, Mac, Web, Windows | API, Linux, Mac, Self-hosted, Windows |
| Lowest paid plan | Free or on request | Not published |
| Plans published | 1 | None |
| Maker | Not published | Not published |
| Website | ast-grep.github.io | comby.dev |
| On code refactoring tools | #1 of 22 | #6 of 22 |
ast-grep: what it does well
- Searches and rewrites code by syntax-tree pattern.
- Interactive CLI previews rewrites before applying them.
- Supports 20+ languages and custom language loading.
- Rule tests can use snapshots.
- Online playground works without local installation.
What to know first
- Some advanced static-analysis information is unsupported.
- A rule cannot target multiple languages at once.
Comby: what it does well
- Matches balanced delimiters while accounting for comments and strings.
- Basic parsers cover a range of programming languages.
- Interactive review helps inspect proposed changes.
- Usable through the CLI, Python bindings, or local HTTP server.
- Free and open source under Apache-2.0.
What to know first
- Indentation is not significant, limiting matches for indentation-sensitive structures.
- Not well-suited to styling or formatting changes such as line wrapping.
- API rewrite ranges report line and column as -1.
- Repeated rewrite hole identifiers currently return only the first range.
Alternatives to ast-grep Alternatives to Comby The whole list