On: The Duct Tape Programmer (Response from Uncle Bob ...

[andreyf]

Good point. I'd argue that either one discourages the other, however. The messier and more complex your architecture, the more valuable tests are. Conversely, the more unit tests you have, the sloppier you can make your architecture.

[kscaldef → andreyf]

And I'd argue the opposite. Messy, complex designs are hard to unit test. Writing unit tests encourages clean, well-defined, orthogonal interfaces.