Contributing to tbot

Hello there! Thank you for taking your time to help tbot become a better piece of software! To make this go as smoothly as possible, please follow the guidelines below:

Commit Style


When sending a pull-request or patch, please make sure to use the supplied pre-commit config. To do so, install the tool and run pre-commit install inside the repository. Now, if you git commit, pre-commit will run a bunch of tests to ensure your changes don’t break anything else!

If you commits touch the module, please also run tbot selftest_tc to make sure nothing broke in there.

Commit Messages

Your commit messages should look like this: <relevant part>: Message in imperative style (present tense)

If your changes apply to tbot as a whole, you can leave out the <module>:. Examples:

board.uboot: Fix bootlog missing if not autobooting
doc: Add flags documentation
loader: Show traceback of errrors
Fix a few spelling mistakes


Always add a signoff-line to your commits. By doing so, you certify the “Developer Certificate of Origin” which can be found at the end of this document.


Please add your changes to in your commits as well. This way, the changelog grows alongside the project and doesn’t need to be written retrospectively. Add your changes under ## [Unreleased], following the conventions from keep-a-changelog.

If your changes require non-trivial downstream fixes, please add a short migration-guide as well.

Coding Style


Your code should always use type annotations and pass a check using mypy. You can most easily check if that is the case by using the supplied pre-commit config.


Formatting convention is black, this is also enforced by the pre-commit config. Just write code however you want and let black format it for you ;)


Please don’t import things into your namespace that you don’t explicitly want to have available for downstream users. Prefer importing the module to keep your namespace clean and to give readers the ability to easily see where some object was pulled in from.


from tbot.machine import channel

# Later on
def foo() -> channel.Channel:


from import Channel

# Now Channel is polluting our namespace :(
def foo() -> Channel:

There might be some exceptions where the latter is definitely perferable, but in most cases it isn’t.


When thinking about how to design your additions, please take some time to check if your ideas follow the Zen of Python. tbot should be kept as elegant and small as possible, we don’t want huge new features in tbot that could also fit into their own module.

Prefer composition over configuration. Or as the kernel calls it: Mechanism, not policy. tbot should be flexible and generic over the users needs. Don’t force anything on the user that they might want differently!

Developer Certificate of Origin

Developer Certificate of Origin
Version 1.1

Copyright (C) 2004, 2006 The Linux Foundation and its contributors.
1 Letterman Drive
Suite D4700
San Francisco, CA, 94129

Everyone is permitted to copy and distribute verbatim copies of this
license document, but changing it is not allowed.

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.