You're reading the documentation for an older, but still supported, version of ROS 2. For information on the latest version, please have a look at Jazzy.

Contributing

A few things to remember before you start contributing to the ROS 2 project.

Tenets

• Respect what came before

  ROS has been around for more than a decade and is used by developers and across the world. Keep a humble attitude and an open mindset while contributing.

• Engage Open Robotics as early as possible

  • Open Robotics acts as a gate-keeper and advocate for the ROS community. Rely on their expertise and technical judgement from the design phase.

  • Start discussions with Open Robotics and the community early. Long time ROS contributors may have a clearer vision of the bigger picture. If you implement a feature and send a pull request without discussing with the community first, you are taking the risk of it being rejected, or you may be asked to largely rethink your design.

  • Opening issues or using Discourse to socialize an idea before starting the implementation is generally preferable.

• Adopt community best-practices whenever possible instead of ad-hoc processes

  Think about your end-user’s experience when developing and contributing. Avoid using non-standard tools or libraries that may not be accessible to everyone.

• Think about the community as a whole

  Think about the bigger picture. There are developers building different robots with different constraints. ROS needs to accommodate requirements of the whole community.

There are a number of ways you can contribute to the ROS 2 project.

Discussions and support

Some of the easiest ways to contribute to ROS 2 involve engaging in community discussions and support. You can find more information on how to pitch in on the Contact page.

Contributing code

Setting up your development environment

To get started, you’ll want to install from source; follow the source installation instructions for your platform.

Development Guides

• ROS 2 developer guide
• Code style and language versions
• Quality guide: ensuring code quality
• ROS Build Farms
• Windows Tips and Tricks
• Contributing to ROS 2 Documentation

What to work on

We have identified a number of tasks that could be worked on by community members: they can be listed by searching across the ROS 2 repositories for issues labeled as “help wanted”. If you see something on that list that you would like to work on, please comment on the item to let others know that you are looking into it.

We also have a label for issues that we think should be more accessible for first-time contributors, labeled “good first issue”. If you are interested in contributing to the ROS 2 project, we encourage you to take a look at those issues first. If you’d like to cast a wider net, we welcome contributions on any open issue (or others that you might propose), particularly tasks that have a milestone signifying they’re targeted for the next ROS 2 release (the milestone will be the next release’s e.g. ‘crystal’).

If you have some code to contribute that fixes a bug or improves documentation, please submit it as a pull request to the relevant repository. For larger changes, it is a good idea to discuss the proposal on the ROS 2 forum before you start to work on it so that you can identify if someone else is already working on something similar. If your proposal involves changes to the APIs, it is especially recommended that you discuss the approach before starting work.

Submitting your code changes

Code contributions should be made via pull requests to the appropriate ros2 repositories.

We ask all contributors to follow the practices explained in the developer guide.

Please be sure to run tests for your code changes because most packages have tests that check that the code complies with our style guidelines.

Becoming a core maintainer

The ROS 2 maintainers ensure that the project is generally making progress. The responsibilities of the maintainers include:

• Reviewing incoming code contributions for style, quality, and overall fit into the goals of the repository/ROS 2.

• Ensuring that CI continues to stay green.

• Merging pull requests that meet the quality and CI standards above.

• Addressing issues opened up by users.

Each repository in the ros2 and ament organizations has a separate set of maintainers. Becoming a maintainer of one or more of those repositories is an invitation-only process, and generally involves the following steps:

• Within the last year, have a substantial number of code contributions to the repository.

• Within the last year, do a substantial number of reviews on incoming pull requests to the repository.

Approximately every 3 months, the ROS 2 team will review the contributions in all of the repositories and send out invitations to new maintainers. Once the invitation is accepted, the new maintainer will be asked to go through a short training process on the mechanisms and policies of the ROS 2 repositories. After that training process is completed, the new maintainer will be given write access to the appropriate repositories.