Henrik Kniberg’s books and musings on agile (Scrum, Kanban, SAFE, Lean) from the trenches. These are among the best and most pragmatic out there. Learn from his hands-on tips and insights as agile coach at Spottify and Lego.

Joel Spolsky’s 4-part blog on how to write painless functional specifications. For every software startup that thinks agile means no spec or documentation is needed.