Type Driven Development

🤔 Test Driven Development is great, but should it be the first thing you do ?

🧬 Data is harder to change than behavior, so instead try Type Driven Development - define the types and interfaces first.

🧭 Then, define the expected behavior with tests.

🛠️ Finally, write the implementation and don't forget about logs and error handling.

In pure Test Driven Development you should define the types/interfaces while you are writing the tests. The difference may seem small but it isn't - due to the complexity of data IMHO defining types should be done as a stand alone step.