All of this serverless stuff looks great in theory, but I'm struggling to understand what the development environment looks like. Does every change in testing g

All of this serverless stuff looks great in theory, but I'm struggling to understand what the development environment looks like. Does every change in testing get deployed to zeit? That seems cumbersome. Otherwise, is there a nice way to test this stuff locally? (Also, how would one set up a database? On a separate service?)