I used to build personal projects like this, but after Postgres got JSONB support I haven't found any reason to not just start with Postgres. There's usually a

I used to build personal projects like this, but after Postgres got JSONB support I haven't found any reason to not just start with Postgres. There's usually a couple of tables/columns you want a proper schema for, and having it all in Postgres to begin with makes it much easier to migrate the schemaless JSONB blobs later on.