This book is a must-have for anyone bringing performance-sensitive Ruby programs to production. It will teach you how to efficiently hunt down and correct the bottlenecks that make users sad and prevent teams from spending time building new functionality.

A fantastic book. Probably the best tech book I have read in the last few years. It brings together information I can’t just find in 30 minutes of web searches. This book has taught me to be a better developer and to start filling a hole in my skill set.

Ruby Performance Optimization has changed the way I develop. I now think about simple performance tweaks before I commit code. It is a book I keep close for reference when solving tough performance issues.

For programmers who aren’t familiar with what is going on “under the covers,” I think this book will open their eyes to new levels of understanding their code.