Git Galaxy 🌌

A flashy, modern Gource replacement. Turns any git repository's recent history into an animated galaxy movie: the default branch is a glowing core, feature branches orbit as spiral arms, authors fly around as comets firing commit particles, and merges explode into the core with shockwaves.

Zero dependencies. One command in, one self-contained HTML file out — double-click it, no server needed.

Usage

npx (no clone needed)

# run from inside any git repo
npx git-galaxy

# any other repo, any range
npx git-galaxy --repo ~/code/my-project --since="1 month ago"

# any repo on GitHub/GitLab/etc — cloned to a temp dir, cleaned up after
npx git-galaxy --repo https://github.com/ngrx/platform

# the entire history, from the very first commit
npx git-galaxy --forever

# open the result
open dist/git-galaxy.html

From this repo

# visualize the repo you're currently in (last 2 weeks)
node generate.mjs

# any other repo, any range
node generate.mjs --repo ~/code/my-project --since="1 month ago"

# any repo on GitHub/GitLab/etc — cloned to a temp dir, cleaned up after
node generate.mjs --repo https://github.com/ngrx/platform

# the entire history, from the very first commit
node generate.mjs --forever

# open the result
open dist/git-galaxy.html

Options

| Flag | Default | Description | | ------------ | ----------------------- | ---------------------------------------------- | | --repo | current directory | Path to a local git repository, or a remote URL (https://, ssh://, git://, git@host:...) to clone and visualize | | --since | "2 weeks ago" | Any git log --since expression | | --forever | (off) | Visualize the whole history — no start date; cannot be combined with --since | | --out | dist/git-galaxy.html | Output file path | | --duration | 90 | Movie length in seconds at 1× speed | | --bots | (none) | Comma-separated extra bot-name keywords (case-insensitive), e.g. --bots "renovate,ci scout" |

What you see

• Core — the default branch (main/master, auto-detected), pulsing at the center
• Spiral arms — branches, each with its own color and label; they grow out on birth and collapse into the core with a shockwave + particle burst when merged
• Comets — authors, flying to the branch they commit to; particle stream size scales with the number of files touched
• Hexagons ⬡ — bots (dependency-update bots, CI agents, …) are drawn differently from humans
• HUD — repo-time clock, live author leaderboard, scrolling event ticker
• Playback bar — play/pause (spacebar), timeline scrubber (seeking deterministically rebuilds the world state), speed 0.5×–8×

Quiet periods (gaps > 4 h without activity) are automatically time-compressed so nights and weekends don't stall the movie.

How it works

generate.mjs runs git log --all plus git for-each-ref, then:

1. Parses commits with file-touch counts (lib/parse.mjs)
2. Merges author identities across name/email variants and flags bots (lib/authors.mjs)
3. Infers branches — GitLab/GitHub-style merge-commit subjects (Merge branch 'X' into 'Y') name the merged branch; commits are assigned by walking first-parent chains from merge points and unmerged branch tips (lib/branches.mjs)
4. Time-warps the event stream onto the movie timeline (lib/timewarp.mjs)
5. Injects the JSON payload into template.html → dist/git-galaxy.html

The template is a single vanilla-JS Canvas 2D app; the page makes no network requests.

Notes & limits

• Branch inference relies on merge-commit subjects. Squash-merge / fast-forward-only repos still work, but branch attribution is limited to unmerged branch tips.
• Repos without an origin remote fall back to local branches.
• Author identities merge on identical email or identical (case-insensitive) name.
• Bot detection defaults to a generic name pattern (bot/automated agent/ci runner). Pass --bots "name1,name2" to add your org's actual bot/service-account names.
• Remote URLs are cloned in full (not shallow), since branch inference needs the real commit graph; large repos will take longer to clone than to render.

Development

node --test lib/*.test.mjs

Requires Node 18+.