Dependabot Core Dependabot Status

Dependabot Core is the heart of Dependabot. It handles the logic for updating dependencies on GitHub (including GitHub Enterprise) and GitLab. We plan to add support for Bitbucket and Azure DevOps in the future, too.

If you want to host your own automated dependency update bot then this repo should give you the tools you need. A reference implementation is available here.

What's in this repo?

Dependabot Core is a collection of helper classes for automating dependency updating in Ruby, JavaScript, Python, PHP, Elixir, Elm, Go, Rust, Java and .NET. It can also update git submodules, Docker files and Terraform files. Highlights include:

  • Logic to check for the latest version of a dependency that's resolvable given a project's other dependencies
  • Logic to generate updated manifest and lockfiles for a new dependency version
  • Logic to find changelogs, release notes, and commits for a dependency update

Other Dependabot resources

In addition to this library, you may be interested in:

  • The dependabot-script repo, which provides a collection of scripts that use this library to update dependencies on GitHub Enterprise or GitLab
  • The API docs for Dependabot's hosted instance (


To run all of Dependabot Core, you'll need Ruby, Python, PHP, Elixir, Node, Go, Elm and Rust installed. However, if you just wish to run it for a single language you can get away with just having that language and Ruby.

The main library is written in Ruby, while JavaScript, Python, PHP, Elm, Elixir, Go and Rust are required for dealing with updates for their respective languages.

Before running Dependabot Core, install dependencies for the core library and the helpers:

  1. bundle install
  2. cd npm_and_yarn/helpers && yarn install --production && cd -
  3. cd composer/helpers && composer install --no-dev && cd -
  4. cd python/helpers && pyenv exec pip install -r requirements.txt && cd -
  5. cd elixir/helpers && mix deps.get && cd -


Dependabot Core has helper classes for seven concerns. Where relevant, each concern will have a language-specific class.

Service Description
Dependabot::FileFetchers Fetches the relevant dependency files for a project (e.g., the Gemfile and Gemfile.lock). See the file fetchers for more details.
Dependabot::FileParsers Parses a dependency file and extracts a list of dependencies for a project. See the file parsers for more details.
Dependabot::UpdateCheckers Checks whether a given dependency is up-to-date. See the update checkers for more details.
Dependabot::FileUpdaters Updates a dependency file to use the latest version of a given dependency. See the file updaters for more details.
Dependabot::MetadataFinders Looks up metadata about a dependency, such as its GitHub URL. See the metadata finders for more details.
Dependabot::PullRequestCreator Creates a Pull Request to the original repo with the updated dependency file.
Dependabot::PullRequestUpdater Updates an existing Pull Request with new dependency files (e.g., to resolve conflicts).

Why is this public?

As the name suggests, Dependabot Core is the core of Dependabot (the rest of the app is pretty much just a UI and database). If we were paranoid about someone stealing our business then we'd be keeping it under lock and key.

Dependabot Core is public because we're more interested in it having an impact than we are in making a buck from it. We'd love you to use Dependabot, so that we can continue to develop it, but if you want to build and host your own version then this library should make doing so a lot easier.

If you use Dependabot Core then we'd love to hear what you build!


We use the License Zero Prosperity Public License, which essentially enshrines the following:

  • If you would like to use Dependabot Core for non-commercial purposes, such as to host a bot at your workplace, then we give you full permission to do so. In fact, we'd love you to, and will help and support you however we can.
  • If you would like to add Dependabot's functionality to your for-profit company's offering then we DO NOT give you permission to use Dependabot Core to do so. Please contact us directly to discuss a partnership or licensing arrangement.

If you make a significant contribution to Dependabot Core then you will be asked to transfer the IP of that contribution to Dependabot Ltd so that it can be licensed in the same way as the above.


Dependabot and Dependabot Core started life as Bump and Bump Core, back when Harry and Grey were working at GoCardless. We remain grateful for the help and support of GoCardless in helping make Dependabot possible - if you need to collect recurring payments from Europe, check them out.