> The problem with modern development is having to nail down the data model first.

Schemaless was one of the original drivers for NoSQL databases.

Now, when I need something schemaless, I start with a Postgres table with an ID and a jsonb or json field... which at least makes it easy to have a schema when the inevitable happens and schema-dependent code ends up getting added to the project.

> To do this every data dependency in the system needs to traceable.

This is a hard problem.