Clean Code: A Handbook of Agile Software Craftsmanship
By: Robert C. Martin
A set of principles and tips not only to level up your code, but to maximize the amount of what scrum calls "work not done" as it will save a lot of developer time on fixing things that shouldn't had evolve to such complex and rigid structures
How many times have programmers faced really hard challenge when trying to make a small, but necessary, change in a monster-size piece of software. Robert C. Martin presents a set of principles, tips, examples and explanations to help you prevent such situations from happening in the first place and second write an elegant code to be read like a book rather than trying to find words in a crossword puzzle. These set of approaches will save a lot of developer time and focus.