Implementing a good code review system into a development process is something that I have found quite difficult to do. The idea of it is conceptually quite simple – just make sure that before code is accepted into the main development stream that it’s reviewed by someone before being allowed to pass. Tools like github compliment git really well but force you down a development path that really suits open source software development, but not necessarily a co-located team.

My problem is that I trust my developers to do the right thing. Ok, so that’s not a problem – it’s actually a really nice place to be. I see code review as a learning exercise for good developers, but I don’t see is as a blocking part of the development cycle. Too many times I have seen code reviews as a blocking step in a software release cycle end up just being a formality to get through.

With that scene set i’ve been thinking of using a karma based code review system. Developers have karma (per project) and can give out positive and negative karma to other developers. At a certain level of karma, the number of reviews required on commits starts to drop off so that eventually a commit by a developer with high karma will not generate a code review (or the percentage of commits submitted for review will be very low). As a project progresses, hopefully this leads to a place where developers who will learn more from having reviews done will have the benefit, while the developers who are well established on the project are able to get code into the project repository without a blocking code review process. Improvement can be measured by karma increasing over time.

Do you have experience with code reviews on projects? (open source vs closed source / colo teams vs non-colo / blocking vs non blocking)… Interested to hear others success and failure stories!