I am so happy Postgres is adding support for JSON. This is a big change. The sole benefit of mongo to me is that you can be flexible with your schema at the beg

I am so happy Postgres is adding support for JSON. This is a big change. The sole benefit of mongo to me is that you can be flexible with your schema at the beginning. But the consequences are * you have to learn to do indexing right later (if you have to scale) * failure and miss starting to occur (as you scale) * more code to write to manage legacy schema and optional fields The last is painful and ugly. Whereas if you start out with a good schema that last point is in a good hand. When you use SQL you always have the restraint that "xyz" attributes are repeating and you can just make a new relation, whereas with mongo you'd stuff 20 fields into a single collection. The refactoring is harder. I will begin to migrate back to SQL for new projects. Also ecosystem is richer in SQL. I have not seen a good ORM for Mongo. MongoEngine is fine but implementation + db have a lot of issues make that ORM a bit unusable from time to time. SQLAlchemy is good. PS: For quick PoC and Hackathon projects sure prototyping with mongo is fine.