108 Quotes by Robert C. Martin

The first rule of functions is that they should be small. The second rule of functions is that they should be smaller than that.

We are confidently commanding, in precise detail, the behaviors of a machine that could otherwise do incalculable damage. And so, programming is an act of supreme arrogance.

Good architecture makes the system easy to understand, easy to develop, easy to maintain, and easy to deploy. The ultimate goal is to minimize the lifetime cost of the system and to maximize programmer productivity.

First Law You may not write production code until you have written a failing unit test. Second Law You may not write more of a unit test than is sufficient to fail, and not compiling is failing. Third Law You may not write more production code than is sufficient to pass the currently failing test.

Adding manpower to a late project makes it later.

Code, without tests, is not clean. No matter how elegant it is, no matter how readable and accessible, if it hath not tests, it be unclean. Dave.

SRP is one of the more important concept in OO design. It’s also one of the simpler concepts to understand and adhere to. Yet oddly, SRP is often the most abused class design principle.

Of course bad code can be cleaned up. But it’s very expensive.

It is a myth that we can get systems “right the first time.” Instead, we should implement only today’s stories, then refactor and expand the system to implement new stories tomorrow. This is the essence of iterative and incremental agility. Test-driven development, refactoring, and the clean code they produce make this work at the code level.