bep/gitjoin: Virtual monorepo made simple. · GitHub

A CLI tool for managing multiple Git repositories as a unified workspace. Define your repos in gitjoin.txt files, and Gitjoin will clone, pull, and prune them for you.

Install via:

go install github.com/bep/gitjoin@latest

If you have hundreds of Git repositories across different technologies and domains, keeping them in separate repositories makes sense — until you need to operate on or configure all (or a subset) of them as a whole.

Examples:

• Share a common AGENTS.md across all Go repositories.
• Share common API keys across all AWS applications.
• Update dependencies in all Go repos.
• Prompt an AI agent to make changes across repos and create PRs.

Git Submodules track a specific commit in each sub-repo and embed that reference in the parent. This is the right tool when you need a pinned, reproducible dependency tree — but it's the wrong tool when your goal is a workspace of independent repos you want to keep up to date.

Gitjoin treats the listed repos as peers, not dependencies:

• No commit in the parent repo when a child repo changes.
• No detached-HEAD checkouts — every repo stays on its default branch.
• Adding or removing a repo is a one-line edit in gitjoin.txt, not a Git operation.
• Shared configuration files (AGENTS.md, firstup.env, …) sit alongside the repos without being wired into their history.

If you need version-pinning, use submodules. If you need a convenient umbrella for many repos you actively develop, Gitjoin is a better fit.

.
├── go
│   ├── AGENTS.md
│   ├── apps
│   │   └── gitjoin.txt
│   ├── firstup.env
│   └── libs
│       └── gitjoin.txt
└── sites
    ├── AGENTS.md
    ├── firstup.env
    └── gitjoin.txt

• gitjoin.txt — one Git repository path per line (e.g. github.com/bep/s3deploy). Lines starting with # are comments.
• firstup.env — environment variables for that branch (see firstupdotenv), typically referencing op:// paths so you can commit this to Git.
• AGENTS.md — AI agent guide for that branch.
• Cloned repo content is automatically added to .gitignore.

Running gitjoin from the workspace root syncs all repositories defined in gitjoin.txt files recursively: clones missing repos, pulls updates for existing ones, and removes repos no longer listed. Note that you can start at any subdirectory with a gitjoin.txt to sync just that subtree.

For repos that would normally be skipped:

1. Stash uncommitted changes (if any)
2. Switch to default branch
3. Pull
4. Unstash (if stashed)

If unstash fails due to conflicts, warn and leave stash intact.