It’s not possible to yank a build at the moment. Although, I can see the use case for that and I’ll try to think of a way to make it happen.
In the short term though, nope, sorry.
This feature is extremely necessary. There should be a butler unpush or similar, as well as a simple delete button in the web UI. The lack of this feature makes me uneasy to start using butler at all. Not even pushing the same --userversion works to replace it - it makes a new one. This isn’t right - even in git you can force push and move/delete tags if you make a mistake.
Currently there’s no way to fix it if someone makes a grave mistake, right? E.g. push a version that accidentally leaks some sensitive info (like server keys, passwords, emails, real names, etc.), or a full version of a game where it was supposed to be just a demo, etc.
My teacher once said “You’re making software, but you’re dealing with humans. They should be allowed to make mistakes, don’t you think? Undoability is extremely important.”.