Is it possible to build an DApp that allows you to track the github, bitbucket issues once if they are accepted by the repository owner, it could give an upvote. In short as long as the contribution of users to git repositories on multiple sites like gitlab, github, bitbucket, etc is accepted by respective project owners in some way, we can say it is contribution. And interface can be used for the voting and earning HIVE & HBD from it. It's not like utopian but a good process to validate and also reward in the process.

Just my 2 cents.