November 11, 2010

We announced recently on the Riak Mailing List that Riak was switching to git and GitHub for development of Riak and all other Riak software. As stated in that linked email, we did this primarily for reasons pertaining to community involvement in the development of Riak. The explanation on the Mailing List was a bit terse, so we wanted to share some more details to ensure we answered all the questions related to the switch.

Some History

Riak was initially used as the underlying data store for an application Riak was selling several years ago and, at that time, its development was exclusively internal. The team used Mercurial for internal projects, so that was the de-facto DVCS choice for the source.

When we open-sourced Riak in August 2009, being Mercurial users, we chose to use BitBucket as our canonical repository. At the time we open-sourced it, we were less concerned with community involvement in the development process than we are now. Our primary reason for open-sourcing Riak was to get it into the hands of more developers faster.

Not long after this happened, the questions about why we weren’t on GitHub started to roll in. Our response was that we were a Mercurial shop and BitBucket was a natural extension of that. Sometime towards the beginning of May we started maintaining an official mirror of our code on GitHub. This mirror was our way of acknowledging that there is more than one way to develop software collaboratively and that we weren’t ignoring the heaps of developers who were dedicated GitHub users and preferred to look at and work with code on this platform.

Some Stats

GitHub has the concept of “Watchers” (analogous to “Followers” on BitBucket). We started accumulating Watchers once this GitHub mirror was in place. “Watchers” is a useful, but not absolute, metric for measuring interest and activity in a project. They bring a tremendous amount of attention to any given project through their use of the code and their promotion of it. They also, in the best case scenario, will enhance the code in a meaningful way by finding bugs and contributing patches.

This table shows the week on week of growth of BitBucket Followers vs. GitHub Watchers since we put the official mirror in place:

Since putting the official mirror in place, the number of Watchers on the GitHub repo for Riak has grown at steady ready, averaging just over 7% week on week. This far outpaced the less than 1% growth in Followers on the canonical Bitbucket repository for Riak.

With this information it was clear that Riak on GitHub as a mirror was bringing us more attention and driving more community growth than was our canonical repo on BitBucket. So, in the interest of community development, we decided that Riak needed to live on GitHub. What they have built is truly the most collaborative and simple-to-use development platform there is (at least one well-respected software analyst has even called it “the future of open source”). Though Mercurial was deeply ingrained in our development process, we were willing to tolerate the workflow hiccups that arose during the week or so it took to get used to git in exchange for the resulting increase in attention and community contributions.

The switch is already proving fruitful. In addition to the sharp influx in Watchers for Riak, we’ve already taken some excellent code contributions via GitHub. That said, there is much left to be written. And we would love for you to join us in building something legendary in Riak, whatever your distributed version control system and platform preference may be.

So when you get a moment, go check out Riak on Github, or, if you prefer, Riak on BitBucket. And if you have any more questions, feel free to email: mark@riak.com.

Mark