MOOSE is a collaborative effort and we always welcome contributions! When contributing to MOOSE you need to keep in mind that hundreds of people are depending on this code to do their jobs every day. Because of that we have specific policies, procedures and automated processes in place to maintain high code quality while allowing many changes to flow into the code daily.

If you are somewhat new to Git or GitHub we have worked up a set of slides to walk you through the processes of modifying MOOSE and submitting patches.

Otherwise a brief overview can be found below:

Code Standards

When modifying or adding to MOOSE you need to follow the strict MOOSE Code Standard. These guidelines ensure a common look and feel to all of the code in MOOSE allowing developers to seamlessly move between sections of code and giving users a consistent interface.

Referencing Issues

Every modification to MOOSE must reference an issue number. This means that every commit that flows into MOOSE must have a #NNNN (where NNNN are the numbers for an issue such as #1234) present in the commit message. Further, every Pull Request also needs to reference an issue number in both its description. Issue numbers are automatically checked for by our testing system.

Work In A Fork

The first step in modifying MOOSE is to create your own fork where you can commit your set of changes:

1. Fork MOOSE

  1. Navigate to
  2. Click the "Fork" button in the upper right: Fork Button
  3. Clone your fork to your local machine (replace "username" with your GitHub username):
git clone

If this returns "fatal: Unable to find remote helper for 'https'" you might be behind a firewall. Try:

git clone

2. Add the upstream Remote:

Add the real MOOSE repository as a remote named "upstream":

cd moose
git remote add upstream

or, if you had a problem with https,

cd moose
git remote add upstream

3. Make Modifications

  • Make your modifications and commit them to a branch (be sure to reference an Issue # in your commit messages.)
git add your_file.h your_file.C
git commit -m "A message about the commit

closes #12345"

See git add and git commit for more assistance on these commands.

Note: The MOOSE team prefers that you format your commit messages as follows:

Short Description or Title of PR (less than 50 characters)
[blank line]
More detail of your PR if needed. 
 - Bulleted lists are encouraged
 - Fixes
 - Enhancements

Reference your ticket using the keyword "closes" if appropriate
to automatically close the issue when your PR is merged.
closes #12345
  • Before contributing your changes you should rebase them on top of the current set of patches in the "devel" branch in the real MOOSE repo:
git fetch upstream
git rebase upstream/devel

4. Push Modifications Back to GitHub

Push your branch back into your fork on GitHub:

git push origin branch_name

Create a Pull Request

GitHub utilizes Pull Requests (PRs) to allow you to submit changes stored in your Fork back to the main MOOSE repository. If you are generally interested in how PRs work you can look at the official GitHub documentation. MOOSE utilizes the "Fork & Pull" collaborative development model.

In addition: our own slides are a great way to learn about the process of submitting a PR for the MOOSE project.

The main thing to remember when issuing a PR for MOOSE is that all PRs should be specified to go to the devel branch.

What Now??

The next phase is covered in How a Patch Becomes Code... that will take you through the process of a PR ultimately making it's way into the master branch in MOOSE...