Quotes from David Thomas

Your knowledge becomes out of date as new techniques, languages, and environments are developed

We find that often the only way to determine the timetable for a project is by gaining experience on that same project. This needn't be a paradox if you practice incremental development, repeating the following steps with very thin slices of functionality: Check requirements Analyze risk (and prioritize riskiest items earlier) Design, implement, integrate Validate with the users

This book will help you become a better programmer.

you shouldn't make decisions based on the internal state of an object and then update that object.

When good-enough software is best [You95], you can discipline yourself to write software that's good enough—good enough for your users, for future maintainers, for your own peace of mind.

we want to avoid creating a "time bomb"—something that sits around unnoticed and blows up at an awkward moment later in the project. By emphasizing testing against contract, we can try to avoid as many of those downstream disasters as possible.

But that ignores the fact that tests are also a way of communicating with other developers, so I now do write tests on code shared with others or that relies on the peculiarities of external dependencies.