First, if you find any bugs or areas to improve, please open issue on GitHub.
In case you would like to implement a patch, note that RedDeer is Eclipse project and you have to have created an account under Eclipse Foundation and signed Eclipse Contributor Agreement. Go through the following section for the details.
Before your contribution can be accepted by the project team contributors must electronically sign the Eclipse Contributor Agreement (ECA).
Commits that are provided by non-committers must have a Signed-off-by field in the footer indicating that the author is aware of the terms by which the contribution has been provided to the project. The non-committer must additionally have an Eclipse Foundation account and must have a signed Eclipse Contributor Agreement (ECA) on file.
For more information, please see the Eclipse Committer Handbook: https://www.eclipse.org/projects/handbook/#resources-commit
Moreover, if you are making a contributinon within your work position, you should read Eclipse Foundation Legal FAQ.
Start with forking the repo and/or clone it locally to your git folder.
$ git clone https://github.com/eclipse/reddeer.git
$ git pull upstream master # in case you want actual state of project
$ git checkout -b name-of-our-branch
Ideally, branch name should corresponds to reddeer github issue, ie. rd-1699
Implement your changes/patch or bug fix... In any case, it is a best way to verify your changes that you run build with tests before you actually make a pull request.
$ git push origin name-of-your-branch
Then you can generate a pull-request and we will make review, discuss, etc. If code is good enough, it can be merged into master.
Contact the project developers via the project's "dev" list.