I've done something similar as an experiment a few years back but I've used Meta Classes which define themselves, to support a schema-less model backed by Mongo

I've done something similar as an experiment a few years back but I've used Meta Classes which define themselves, to support a schema-less model backed by MongoDB. It felt like a more flexible and correct approach at the time. In the end after my experiment ended, I've scrapped it decided to wait for PostgreSql 9.4 to be released with the BJSON field support. Then JSONField was my new friend.