Code reviews are a popular method of catching bugs early in development through peer-reviewing someone’s code. But perhaps more important than catching bugs, these reviews also serve as a chance to see how something is built and have a conversation about it. Because testers question software differently from developers, it’s important that we participate in this knowledge-sharing practice.
In May 2006, we wrapped up the largest case study of peer code review ever published, done at Cisco Systems®. The software was MeetingPlace® — Cisco's computer-based audio and video teleconferencing solution. Over 10 months, 50 developers on three continents reviewed every code change before it was checked into version control. We collected data from 2500 reviews of a total of 3.2 million lines of code.