Why OpenBSD Developers Use CVS

The Concurrent Version System (CVS) was selected for use by the OpenBSD project group at the initial establishment of the project. With CVS, OpenBSD developers are able to update the source code (which is currently about 2.5GB, 280,000 files) that comprise the OS, ports/packages, the X Window System and the website. OpenBSD pioneered the use of anonymous CVS, which allowed anyone read-only access to the CVS repository so they could access the most recent code, the change history and the commit messages within an hour or two of the change being made.

With CVSweb, a convenient and navigable web accessible interface to all of this is available as well.

Since OpenBSD was founded, other version control systems have come along, and people often wonder why OpenBSD still uses CVS. Short version: it works well for us and does what we need it to do. Longer version:

Changing version control systems would mean developers must spend time learning something new and many systems would need to be reconfigured. Very little time is spent working with CVS, which is as it should be and it is unlikely the time spent learning and implementing a new system would ever be recovered.