Git File Matrix

Visualise which files were touched by which commits so you can untangle long branches and spot logical change groups.

Demo: https://straz.to/git-touch-matrix/

About

Git File Matrix is a visual tool for understanding how a branch evolved.

Large branches often start cleanly, then grow across dozens of commits and files. Even with decent commit hygiene, it becomes hard to see where one piece of work ends and another begins, especially when later commits revisit earlier architectural changes.

Git File Matrix makes that easier by turning Git history into an interactive file-by-commit matrix.

• Columns represent commits
• Rows represent files
• Cells show when a file was touched by a commit

This makes it much easier to spot related change clusters, follow the spread of a refactor or feature through the codebase, and identify clean boundaries for branch splitting, rebasing, or cherry-picking.

You can use it in two modes:

• Paste raw git log output into the browser for a fully static workflow
• Run the local Python server to generate and refresh matrix data automatically from a repository

Git File Matrix is useful for refactoring, stacked branches, code archaeology, branch cleanup, and any situation where you need to answer: "what actually changed together?"

Running it yourself

Build the web UI

cd git_file_matrix/web
npm install
npm run build

This produces static assets in git_file_matrix/web/dist.

Generate JSON

python3 git_file_matrix/git_file_matrix.py origin/main..HEAD --out git_file_matrix/matrix_data.json

Without --out, JSON is written to stdout.

Generate + serve UI

python3 git_file_matrix/git_file_matrix.py origin/main..HEAD --serve

Optional flags:

• --host 127.0.0.1
• --port 8765
• --open-browser

If assets are not built, the script prints an instruction to run the web build.

While serving, matrix_data.json is refreshed automatically when HEAD changes.
During an active rebase, refresh is paused to avoid noisy churn, then refreshed once after rebase completes.

Frontend-only development loop

Terminal 1:

python3 git_file_matrix/git_file_matrix.py origin/main..HEAD --out git_file_matrix/web/public/matrix_data.json

Terminal 2:

cd git_file_matrix/web
npm run dev

Open the dev URL from Vite. The app loads ./matrix_data.json by default.

You can override the data path with ?data=..., for example:

http://localhost:5173/?data=./matrix_data.json

Static demo mode (no served JSON)

The UI always shows a data input panel.
If matrix_data.json is unavailable (for example on static hosting like GitHub Pages), paste raw output from:

git log --reverse --name-only --format=COMMIT\t%h\t%s origin/main..HEAD

Click Load pasted data to parse and render the matrix entirely in-browser.