You can contribute to the Threema apps through pull requests on GitHub. Please follow the steps below:

1. Preparation

If you want to make a larger change to the Threema apps, we recommend that you contact us first via e-mail to opensource@threema.ch to explain your plans. This way, we can give you early feedback about your idea, before you spend the time to actually implement the change.

Please mention the following:

  • What you would like to implement
  • How you would like to implement it

2. Sign the CLA

We require all contributors to sign our Contributor License Agreement (CLA) for non-trivial contributions. Please ensure that you have signed it before submitting a contribution.

Note that at all times you retain full ownership of your contributions. We only require a copyright license, not a copyright transfer.

3. Apply Your Changes to a Branch

Fork and clone the git repository you wish to modify.

$ git clone git@github.com:<your-user>/threema-<platform>.git

Create a new branch.

$ git checkout -b my-feature-or-fix

Apply your changes, test, and commit them.

4. Send a Pull Request

Once you are done, push your branch to GitHub and open a pull request.

Please understand that we cannot guarantee that we will accept your contribution. A bug may have already been fixed in our development version, a contribution may conflict with another contribution, or we may have other plans for Threema’s development. Nevertheless, you will hear back from us.