Documenting provenance is hard. I'm considering releasing some projects under CC0, and I would like users to feel highly confident about using the material, wh

Documenting provenance is hard. I'm considering releasing some projects under CC0, and I would like users to feel highly confident about using the material, which for anything I'm the sole author of would be fine because I have a decent reputation (past ASF board member). However, accepting contributions from others would require assessing their right to contribute and documenting it. Any patches which show up from a previously unknown author are potentially a curse rather than a blessing. At the least, I have to vet the author. If I can't do that, or don't want to spend the effort, then not only can I not use the contribution, if I want to write my own patch I have to do in such a way to avoid creating a derivative work. I'd rather just get a feature request, it's less trouble! I'd like to put the CC0 projects on Github for the convenience of users, but the problem is that Github's culture of contribution doesn't meet my requirements and you can't turn off pull requests short of "archiving" the repo. I might do something like maintain the project elsewhere and put an archived mirror on Github, running a script once per day which unarchives the repo, pushes changes, and rearchives the repo... Public domain art aggregator sites like Artvee aren't ever going to be able to offer a level of care like this. Users who are serious about copyright need to be able to verify provenance to high degree of confidence, and Artvee can't vet uploads to that standard or they wouldn't have any inventory.