Contributing to libmaple

First of all, thanks! Community contributions are what makes open source great.

If your patch is minor (you’ve found a typo, you’ve added a new function, etc.), feel free to just make a forum post describing your changes.

If your changes are larger (you wrote a new library, you added support for a new peripheral, etc.), we’d prefer you submit a pull request on GitHub or send us a nicely-formatted patch via email.

Preparing Your Patch

Before submitting a patch, please make sure it complies with the coding standard. Consistent style throughout the source tree is an important implementation objective for us, and a patch that doesn’t comply with the coding standard we’ve set forth is likely to be sent back until it follows the standard.

We would prefer if you release each new file you submit under the MIT license. See e.g. bkp.h for an example, and the coding standard for more details. Code released under the Lesser GPL may be accepted for Wirish, but will almost certainly be rejected for libmaple proper. We will not accept patches released under the GPL.

We’re not against the GPL! It just doesn’t suit our purposes for libmaple. If you’re interested in a GPLed library for ST microcontrollers, check out libopenstm32. Also note that libraries released under the GPL are fine, we just don’t want any core libmaple or Wirish code to be GPLed.

Submitting Via GitHub Pull Request (Preferred)

The most convenient way for you to contribute patches is to submit a pull request on GitHub. Github provides excellent code review interfaces, which will make it easy for us at LeafLabs to communicate with you (and each other) about your patch. It also makes it easy for us to merge your patch into the libmaple source tree when the time comes.

The steps to submit a pull request are as follows:

  1. If you don’t already have one, get a GitHub account (free).

  2. Fork libmaple, then clone your fork to the computer you code on. GitHub provides detailed instructions on forking and cloning a repository.

  3. Push your commits to your GitHub libmaple fork (see instructions linked in Step 2 for a step-by-step walkthrough on how to do this).

    Please add a signed-off-by line to your commits which certify your developer certificate of origin [1]. For example, if your name is “John Smith”, and your email address is “”, just include the following line at the bottom of your commit messages:

    Signed-off-by: John Smith <>

  4. Submit a pull request to the LeafLabs version of libmaple.

Submitting Via Email

If you’re unfamiliar with Git or would prefer not to use GitHub, you can always send us a patch via email at We’d love it if you used the Linux kernel patch format, but please at least include the following information in your email:

  1. How you generated your patch (arguments to diff, etc.)
  2. What git branch/commit or libmaple version your patch applies to
  3. A one-line summary of your changes, along with any other details you think we should know.
  4. A sign-off line certifying your developer certificate of origin [1].

Git Resources

If you’d like to learn more about Git, we recommend the following resources:


[1](1, 2)

Including this line indicates that you certify the following:

Developer's Certificate of Origin 1.1

By making a contribution to this project, I certify that:

(a) The contribution was created in whole or in part by me and I
    have the right to submit it under the open source license
    indicated in the file; or

(b) The contribution is based upon previous work that, to the best
    of my knowledge, is covered under an appropriate open source
    license and I have the right under that license to submit that
    work with modifications, whether created in whole or in part
    by me, under the same open source license (unless I am
    permitted to submit under a different license), as indicated
    in the file; or

(c) The contribution was provided directly to me by some other
    person who certified (a), (b) or (c) and I have not modified

(d) I understand and agree that this project and the contribution
    are public and that a record of the contribution (including all
    personal information I submit with it, including my sign-off) is
    maintained indefinitely and may be redistributed consistent with
    this project or the open source license(s) involved.

This may seem arbitrary, but it helps ensure that libmaple remains open source.