Most software doesn’t survive very long. The hard truth is that more than 80% of the open source software being written today will be forgotten in a few years.
For those projects that do succeed and thrive, the developers typically decide at some point that they need a new source control system. For many reasons (lack of time, lack of tools, or a simple desire to start fresh), most projects simply throw away their development history at this point and start again.
All of which means that most source control repositories are lucky to survive more than a couple of years.
However, there’s a class of meticulous, responsible, (obsessed?) programmer that somehow manages to keep the same thread of development alive and unbroken for decades.
Among the 14,000 repositories Ohloh is currently tracking, here are the three oldest open source repositories — all three of which are still under continuous development today. [And if we're missing something, please let us know!]
Started in November 1988
This building block of the open source world is all the more impressive for surviving a conversion from RCS through CVS and into Subversion. Ohloh found 350 developers listed in this repository, two of which have over 10 years of development experience.
Started in April 1985
No matter which side of the Emacs/Vim debate you come down on, you have to hand it to this team for keeping their CVS repository alive for over 22 years. And yes, rms is still hacking away after 20,000 commits. Impressive.
Started in April 1983
When this open source repository was getting started, I was saving my pennies for a Sinclair ZX-81 kit. That computer and all its code are long gone, but BRL-CAD marches on. Not surprisingly, BRL-CAD developers were very helpful in wringing obscure bugs out of the Ohloh CVS parser [thanks sean!].