For too long, code reviews have been too much of a chore. This is largely due to the lack of quality tools available, leaving developers to resort to e-mail and bug tracker-based solutions.
We have seen a lot of time and energy wasted doing code reviews as code reviews were typically done over e-mail. A significant amount of time was spent in forming review requests, switching between the diff and the e-mail, and trying to understand what parts of the code the reviewer was referring to.
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rietveld is a code review tool written in Python (of course!) and hosted on Google s own experimental cloud-computing framework AppEngine. Anyone with a Google account can participate; after logging in you can identify Subversion repositories and branches containing code that needs to be reviewed, upload changed source code files, and invite reviewers. Reviewers can see an online diff and leave their own comments, and the system uses email notifications to keep the discussion moving along.
Codestriker is an open-sourced web application which supports online code reviewing. Traditional document reviews are supported, as well as reviewing diffs generated by an SCM (Source Code Management) system and plain unidiff patches. There are integration points with CVS, Subversion, Clearcase, Perforce, Visual SourceSafe and Bugzilla. There is a plug-in architecture for supporting other SCMs and issue tracking systems.
JCR is a web-based tool for performing and managing code reviews. It can be used for code in any language, but provides some extra features for Java.
Review Board is a powerful web-based code review tool that offers developers an easy way to handle code reviews. It scales well from small projects to large companies and offers a variety of tools to take much of the stress and time out of the code review process.