I've been challenging myself in a current work project. I don't want duplication in tests and I want most methods to have zero setup. The high level tests ideal

I've been challenging myself in a current work project. I don't want duplication in tests and I want most methods to have zero setup. The high level tests ideally should just start with a get-request and go straight into expectations. For one, this has resulted in a curious structure. I have a 5 or 6 fixtures with representative sample datasets used in production and these get extended as new features are introduced. If some new addition breaks everything, we'll know immediately, as all tests use the same fixtures and it's all just one place. And it's also instructive during design. These fixtures give you 3-4 situations to think through when adding something new. And the tests are pretty. Most of them have been boiled down into one test_client request and a comparison with a dataset, just 2-3 logical lines. This makes is easy to see if tests are still correct, necessary. Or to just talk about if they make sense overall, even with less technical or involved people.