Full migration framework
@mekanix -- https://github.com/cam-stitt/arnold is one such project I'm aware of. I don't have plans for adding anything more than what is already present in the `playhouse.migrate` module. Perhaps you can bring this up on the mailing list? https://groups.google.com/group/peewee-orm

In short, if anyone is working on full fledged migration framework, I'd like to contribute. If nobody is working on it, I'd like to do it. Any pointers on how to contribute/implement migrations ala Django (or maybe something better?) are welcome.
