Frink provides basic ORM-like functionality for RethinkDB on top of Schematics. Flask-Frink adds support for using Frink with Flask and includes datastore classes for Flask-Security.
WARNING: This is totally pre-alpha at the moment. Things are likely to change. If you're interested in using it in production, then contributions to get it somewhere stable would be much appreciated.
Don't use it yet.
Don't install it yet.
Requires the excellent schematics, the rethinkdb driver, and inflection.
Tested with Python 2.7.6 and Python 3.4.3