A PR has been opened on the Tenacity GitHub repo [1], which adds a
CONTRIBUTING.md file which explains how to contribute to the project
through sourcehut or GitHub.

This commit also adds a requirement to sign the Developer Certificate of
Origin (DCO). This has been partially discussed on IRC.

A Developer Certificate of Origin (DCO) is used in projects big and
small to ensure that liability falls on the person who wrote the commits
if they violate any licenses. You need to "sign off" your commits by
adding 
    Signed-off-by: user <email@email.email> 
to the last lines (where Co-authored-by, etc reside).  
We have decided to go this way due to a sign off being permanent and
verifiable in the commit history, unlike GH issues/sourcehut mailing
list archives.

A summed up version of it is: 
    You're either submitting your own work, or affirming that you have
    permission to submit another person's work under this license, while
    keeping the original contributor's copyright over the code.

Currently unmerged patches/PRs will be requested to sign-off their
commits.

[1]: https://git.io/Jc5vV