Debugging: The 9 Indispensable Rules for Finding Even the Most Elusive Software Bugs

Debugging is the shortest book on my shelf and one of the most useful. Agans' nine rules—understand the system, make it fail, quit thinking and look, divide and conquer—are deceptively simple, but they've saved me hours of frustration. The rule about making it fail is gold: if you can't reproduce a bug, you can't fix it, and Agans shows how to systematically make bugs reproducible. The section on divide and conquer helped me understand why binary search works for debugging too: narrow down where the bug is, then narrow it down again. The book is short—you can read it in an hour—but every page is packed with insights. I've recommended it to junior developers who were struggling to debug issues, and it's helped them develop a systematic approach instead of guessing. My only critique is that some examples feel dated, but the principles are timeless. Essential reading for anyone who debugs code, which is everyone.