(Cross post from #7278 <Issues · rails/rails · GitHub)
Now that ActiveRecord supports uuid datatypes (#6713<Issues · rails/rails · GitHub) I suspect that having UUID instead of auto-incrementing primary keys will become fairly popular. It's already possible to do this yourself but perhaps it should be built into ActiveRecord?
Just a hunch, but I don't think much needs to be changed in AR. If we're doing anything in AR to assume that the id is an integer, it's probably a bug.
The main place where we'll need changes is in migrations and schema.rb generation.
I'm happy to contribute a patch but was wanting to solicit feedback on wether this is wanted and if anybody had ideas on how the configuration should go.
I think the main changes will be in the migrations. Probably need to somewhat change the api of the create_table method calls. If you can get something working (even partially) send a link here, or a PR and we can work on it together.