Let us think a bit about the kinds of tests we need.

Our service must read and create data in the JSON format. This format should be fixed and changes to it should raise red flags because any changes would mean that our API just broke.

We want to unleash the power of ScalaCheck to benefit from property-based testing. But even when we’re not using that, we can still use ScalaCheck to generate test data for us.

In addition to the regular unit tests, there should be integration tests if a service is written. We can test a lot of things on the unit test side, but in the end, the integration of all our moving parts is what matters, and often (usually on the not-so-pure side of things) we would have to mock a lot to test things in isolation.