Kevlin Henney is an independent consultant, speaker, writer, and trainer. His software development interests are in patterns, programming, practice, and process. He has been a contributor, columnist, and advisor for software development magazines and websites, including The Register and IEEE Software. He is coauthor of A Pattern Language for Distributed Computing and On Patterns and Pattern Languages, two volumes in the Pattern-Oriented Software Architecture series, and editor of 97 Things Every Programmer Should Know.