The book Basecamp wrote about how it built Basecamp, before that was a genre. Each chapter is a page and a rule: Build less. Fix time and budget, flex scope. Interface first. Epicenter design — start with the one thing the screen exists for and design outward. Copywriting is interface design. Don't write a functional spec. It reads fast because it was written to be argued with, and most of it has been.
Read it for the through-line this garden borrows: the words on a screen are part of the design, not a pass after it; a smaller thing that ships beats a larger thing that is specified; and constraints — a team of three, a deadline, no funding — are where the design comes from. Shape Up, thirteen years later, is the same company's answer to how that scales.
Free at basecamp.com/gettingreal; an afternoon, or one chapter whenever a meeting needs a sentence.