Basejump

Basejump is a GitHub App that automates the rebasing of pull requests on-demand.

Overview

Basejump monitors pull request comments on your repositories. When a comment starting with /rebase is posted on a pull request, Basejump attempts to rebase the PR branch onto its base branch.

How It Works

Triggering a Rebase

To trigger a rebase, simply comment on a pull request with:

/rebase

Process Flow

1. Basejump listens for new issue comments and begins the rebase process when a comment starts with /rebase on a pull request.

2. An eyes reaction (👀) is added to the comment to indicate the request was received and is removed once the process completes.

3. Basejump checks if rebasing is necessary; if the PR branch is already up-to-date with its base branch, it adds a confused reaction (😕) and exits.

4. If rebasing is needed, Basejump performs the operation using a cherry-pick approach since GitHub's API doesn't offer a direct rebase function.

5. Upon completion, Basejump adds a rocket reaction (🚀) for success or a confused reaction (😕) for failure, with an explanatory comment for code conflicts that require manual resolution.

Implementation Details

• Basejump operates as a GitHub App using the Probot framework
• It uses the GitHub REST API to manage repositories, pull requests, and reactions
• Since GitHub doesn't provide a direct rebase API, Basejump implements its own rebasing mechanism using cherry-pick

Limitations

• Cannot rebase pull requests that would result in merge conflicts (requires manual intervention)
• Does not sign rebased commits, due to limitations of GitHub's REST API

Setup

# Install dependencies
npm ci

# Run the bot
npm start

Docker

# 1. Build container
docker build -t basejump .

# 2. Populate .env as needed

# 3. Start container
docker run -e APP_ID=<app-id> -e PRIVATE_KEY=<pem-value> basejump

Contributing

If you have suggestions for how basejump could be improved, or want to report a bug, open an issue! We'd love all and any contributions.

For more, check out the Contributing Guide.

License

Apache-2.0 © 2025 Balena