We welcome contributions, and have tried to make it as easy as possible to make contributions. This applies to how we handle the legal aspects of contribution. We use the same approach—the Developer's Certificate of Origin 1.1 (DCO)—that the Linux® Kernel community uses to manage code contributions. We simply ask that when submitting a pull request, the developer must include a sign-off statement in the pull request description.
Here is an example Signed-off-by line, which indicates that the submitter accepts the DCO:
Signed-off-by: John Doe <john.doe@hisdomain.com>