Lenz Grimmer's blog

Even though we had been preparing the migration to Bazaar for a while now, today's announcement kind of caught me by surprise. But I am very happy about this move!

While BitKeeper is an excellent tool and served us well the past eight (!) years, I was quite annoyed when BitMover decided to remove the fully functional free BitKeeper client, which effectively put our development back into a Cathedral: even though our source trees remained accessible via bkbits.net, the crippled bk client was only capable of cloning and pulling new revisions from there - it was not possible for an external developer to commit changes locally or to create patches. This turned out to become a severe roadblock for users that wanted to participate in the development of the server. While some of our other internal projects (like the documentation, connectors and GUI tools) moved to Subversion, this was not that easily doable for the MySQL Server source trees. Lots of internal processes and tools had been tightly coupled with the source code management and there never seemed to be the right time to make the switch, which potentially could have disrupted the ongoing development work.

By moving to a truly open, distributed revision control system, it will become much easier for external contributors to work on patches and maintain modifications or enhancements outside of the main MySQL Server source trees. In fact, work has already begun! When I look at the various repositories hosted on Launchpad.net, I already notice several source trees that are not maintained by MySQL Engineers, e.g. Marc Callaghan's Google patches, Percona's work on microsecond resolution or a branch of MySQL 5.0 that is maintained and used by the folks from Wikimedia. I too helped publishing a source tree today - Holyfoot's work on improving the GIS functionality is now also available from there! In addition to the MySQL Server, many other MySQL-related projects are hosted on LaunchPad. And by utilizing services like the fabolous OpenSUSE Build Service, it's actually quite easy to provide readily installable packages of these as well!

I hope this change will significantly lower the barriers for external contributors and make it easier for our own developers to merge and accept changes that have been created by others and received sufficient community testing. This is much more convenient than having to apply a patch that was posted a long time ago and may have already been abandoned by the contributor or suffered from bit-rot. Being able to maintain a patch within a live tree that can be kept in sync with the main repository is one of the great features of distributed revision control (and which I think is one of the technical reasons why the Linux Kernel development model works so well).

Kudos to everybody involved in making this happen!