Regarding documentation, check out Docs for Developers by Bhatti et al. The subtitle describes the book as "an engineer's field guide to technical writing" and that's exactly what the book is. It provides you a detailed step-by-step overview of what high-quality documentation process and output looks like. I've been a technical writer for 9+ years and can vouch that anyone following the blueprints laid out in that book will probably end up with significantly better docs.