TDD at the System Scale

System tests have the reputation of being slow (not entirely avoidable, I admit), difficult to automate reliably and difficult to diagnose when they fail. However, I find that many teams follow a TDD process at the unit-level, but do post-hoc testing at the system level, and so don’t use system tests as a source of design feedback. This blog post shows how you should do TDD at the system scale.