### Problem to solve [Developer Certificate of Origin](http://developercertificate.org) (DCO) is an attestation from a code contributor that they have the rights to submit the code in their commit. This is supported natively by `git` through the `-s` flag when creating a commit. Here is an excerpt for that flag from the `git-commit (1)` man page: ``` -s, --signoff Add Signed-off-by line by the committer at the end of the commit log message. The meaning of a signoff depends on the project, but it typically certifies that committer has the rights to submit this work under the same license and agrees to a Developer Certificate of Origin (see http://developercertificate.org/ for more information). ``` Since this is supported natively by git from the command line it should also be supported by GitLab's web interface and it should be simple for project admins to require without needing to utilize regex. Without an option to add "Signed-off-by" lines to commits made through the web, contributors need to manually type in the DCO line on every commit and merge they perform. This is tedious for developers and may cause enough of an annoyance to stop them from contributing. For project admins, enforcing DCO on projects through a "Require expression in commit message" [push rule](https://docs.gitlab.com/ee/push_rules/push_rules.html#custom-push-rules) regex is unwieldy as it has to match "Signed-off-by" followed by any name and [email address](https://www.emailregex.com/). Further, if as a group owner wants to require all their projects to follow DCO, they would need to copy the regex to every project. ### Proposal See the issues listed below. We can work in parallel on some. ### Release notes Users can now add a DCO 'Signed-off-by' line to commits from the web, and project owners can now require users sign-off their commits. ### Further details Initial discussion started in https://gitlab.com/gitlab-com/marketing/community-relations/open-source-program/linux-foundation/-/issues/4