> at least mentally. Even without TDD, that's kind-of how I go: I'll have the top-down general structure in mind, but not in the code, and write the actual co

> at least mentally. Even without TDD, that's kind-of how I go: I'll have the top-down general structure in mind, but not in the code, and write the actual code bottom-up. That way I encounter problems with the implementation details sooner, and can more readily adjust the overall structure without feeling bogged down by what's already written. In the broader structure though it's more like a through-line: One nice input/output, written in that bottom-up-with-top-down-in-mind way, all the way through a use case, then expand sideways with the other inputs/outputs built on the same lower-level functionality.