- Published on
Commit-rewriter 0.1
- Authors
- Name
- DeepHorus
Simon Willison released commit-rewriter 0.1 on September 14, 2026, a Python web application for rewriting Git commit messages. The tool is designed to clean up commit histories before publication. Willison built it specifically to edit commits for the Datasette security releases, where initial messages contained coding-agent artifacts and private issue references. The release appeared on his personal weblog.
The app runs locally and is launched through a simple command-line invocation. Users can run "uvx commit-rewriter path/to/repo" to point the tool at a target repository. If they are already inside the repository directory, they can omit the path entirely. The interface then opens in a browser, allowing developers to revise commit messages visually.
When edits are submitted, commit-rewriter creates a timestamped branch reflecting the current repository state. This branch acts as a backup, so users can revert if the rewrite produces unwanted results. The tool then rewrites every commit from the first edited message to the most recent one. This approach preserves the code changes while replacing only the commit messages, according to Willison's description.
Willison explained that the original commits for the Datasette security releases were not fit for publication. They included "coding agent cruft" and issue IDs from a private repository. Manually fixing such messages across many commits would require complex interactive rebasing. commit-rewriter automates that chore with a focused web interface and a reversible branch.
The release underscores a growing challenge in AI-assisted programming. As coding agents generate more commits, their output may contain internal references or low-quality messages that should not be public. Developers need tools that can sanitize history without altering the actual code. commit-rewriter addresses that need by combining a lightweight Python application with Git's existing rewrite capabilities.
Version 0.1 signals an early-stage project. Willison published it alongside recent articles on GPT-6 running routes, OpenAI agents attacking RubyGems, and the Navier-Stokes Millennium Prize Problem. He tagged the post with "git," "python," and "ai-assisted-programming," reflecting the tool's intersection of software maintenance and AI workflows.
The tool is available immediately for developers who want to try it. Its future development will likely depend on feedback from users who manage repositories with messy or private commit histories. For now, commit-rewriter 0.1 offers a practical way to make Git history safe for public release. It remains a small but useful addition to the ecosystem of Python-based developer utilities.
