Mesos Developer Community Status Report

The Mesos project has a large and rapidly growing community of users and contributors. In this post we would like to reflect on the current state of the community as well as speak about some benefits and challenges that the growth brings.

One of such challenges is that the we have to make sure that everyone’s interests are met. This isn’t always easy due to occasional conflicts of interest. For example, developers are eager to see their patches vetted and committed to the codebase as rapidly as possible, whereas production users of Mesos want to make sure that the stability of the software is never compromised for the sake of rolling out new features. Both are essential components of a healthy open source infrastructure project, and we want to strike a harmonizing balance.

Transparency is the key for being able to grow the community while also making sure that participants understand and agree with the development direction. In this post - much of which derives from a recent MesosCon 2016 presentation - we are going to present some statistics that reflect the current state of the community participation. The time frame for the following statistics ranges from the 0.24 release (July 2015) until 1.0.0-rc2 (June/July 2016).

We mined the data for this post from Mesos git log and used the recently added contributors.yaml file for mapping contributors to organizations.

Community Growth and Diversity

The number of unique contributors has been increasing steadily over time. As of this writing, the number of contributors for the most recent release is greater than 100. This is a more than factor two improvement over the 0.24 release for which there were about 50 unique contributors!

Historically there have always been large organizations from which the significant amount of contributions came from. In recent times, Mesosphere, IBM and Microsoft have been leading in terms of number of contributions made to the codebase. However, in terms of numbers of people, the individual contributors greatly outnumber those from Mesosphere, IBM and Microsoft.

This is a great milestone for all of our individual contributors out there! We greatly appreciate your contribution to the project and we’re looking forward to seeing even more commits from individual contributors in the future.

In terms of numbers of commits from an organization, Mesosphere has the highest number after contributing 62.8% of the commits. It is followed by ‘Other’ (which is a default organization for all the authors who do not have an affiliation entry in the contributors.yaml), IBM and Microsoft. We are actively working on involving more members from the community and are looking forward to seeing an even greater community participation.

It is important to note that 1.0 release has been in the making for a longer time than previous releases, and that is why there is a significant spike in the number of commits for 1.0-rc2. Here is how the same graph looks like once we change the breakdown from releases to months.

It presents a fuller picture where the upward trend is still there, but one can also notice that the smooth growth trend has been there for a while.

The last graph that we want to present shows the breakdown of commits per release between contributors and the PMC members (aka Mesos Committers). As one can see the number of commits authored by non-committers vastly outnumbers the ones originating from committers. This shows that the active committers spend a lot of time shepherding and landing patches from contributors.

Going forward we are going to introduce a page on our website where we will continuously publish up-to-date statistics around the developer community. We are also going to double down on initiatives to improve the contribution experience on the Mesos project. We started by doing a spring cleaning on our GitHub and Reviewboard backlogs, as well as the Kanban board in JIRA. This will make sure that shepherds do not get drowned in stale reviews, and that everyone can see what the community is working on. We also have some ideas around improving the developer tools, collecting and analyzing metrics around reviews, as well as some other initiatives that should foster a greater participation. If you are interested in helping us improve the community participation and drive some of these initiatives please join the ‘Community’ working group.

Stay tuned for more news on the dev list!