This is great!

One point I would like some clarity on is the migration process. Assuming I use this for a production application, how do I maintain changes of my model schemas, and how are these migrations applied? Can I rollback?

I think a solid story on these would make a library like this extremely attractive. (One of the reasons Rails enjoys developer mindshare is it's amazing migrations workflow).

Thanks for bringing this up. Currently there's no migration process. Like Mongo, Expressa only ensures validity of new data, but doesn't change old data so it's up to the application to handle that.

This is definitely something I would like to eventually support though so that renaming fields and other data changes are easy.

One of the main features is that it provides an admin interface which lets you modify your data as well as your collection schema. I got tired of Django, keystone and other CMS that require defining schema in code and have found this to be a good solution for my projects.

very cute :D thanks for share