kranzky

At Team Bondi we used Perforce, and I loved its Timelapse View, which I've missed badly since moving to Git many moons ago. So I finally built it, inspired by the Handmade / Better Software crowd and Jon Skinner's Sublime Text (Jon and I worked together on L.A. Noire).

Git Lineage allows you to

* open a file in a Git repo and drag the timeline. The view updates at up to 120fps while you drag. Lines are tinted by how recently they changed, and deleted lines linger as fading ghosts;

* search in realtime across the whole revision history, with matches shown on the timeline, and you can jump from one matching commit to the next, with results filtered by added or changed lines, deleted lines, or commit metadata;

* blame directories too, even to the point of double-clicking into a sub-directory deleted years ago to dig through the files within it; and

* much, much more; there's a user's manual and a video on the website that go into the details (I tested on the Linux repo, which the video shows, and also on the Rails repo).

Oh, I almost forgot: press E and Q to enable visual effects and sound effects, so scrubbing through history feels like being a hacker in a 90s movie ;)

Git Lineage was built with C++17, Dear ImGui on SDL3's GPU API, FreeType, libgit2 for objects and diffs, and the git CLI for history and blame. Blame for commits near the playhead is computed on background threads and cached in memory and on disk, and the cache evicts by distance from the playhead so it follows you as you scrub. On my M1 Pro, with a synthetic file of 1,000 commits and 5,000 lines, the first view appears in about 250 ms and moving to a cached revision shows new content in about 8 ms.

Confession time: This project was AI-assisted. I built it with Claude Code over six and a half months, shipping over 330 PRs, each one reviewed, tested by hand and merged by me. And I had to be very hands-on throughout actually, especially with performance, the blame caching and prefetching that make scrubbing smooth, threading bugs, and the UX.

Limitations: Git must be installed. Rename following is opt in and off by default. Merges make some transitions ambiguous. The first open of a big repo takes a while (you'll probably not notice a delay on your own projects). It is a history viewer, not a Git client: no staging, committing or branching or other features. Keep using what you're using, reach for Git Lineage when you have some code spelunking to do.