Activity Traces and Signals in Software Developer Recruitment and Hiring

Online peer production sites such as GitHub have the potential to change the way software developer recruiting and hiring occurs.  Member profiles on GitHub provide an archived, visible history of detailed traces of an individual’s work actions and discussions around open source projects.

These are publicly viewable in a way that was previously inaccessible to employers.  Indeed, there is anecdotal evidence that this information is viewed as a more accurate representation of an individual’s skills and work style than information listed on a resume.

Sample GitHub profile
Sample GitHub profile (at the time of research, in early 2012)

Our research investigated the implications of this increased transparency for hiring and recruiting software developers.  We conducted interviews with both employers and job seekers who used GitHub to understand:

  •  How employers use activity traces to find and evaluate potential hires
  • How job seekers attempt to manage the impressions their activity traces give off

We interpreted our results using the lens of signaling theory to understand which kinds of traces were viewed as more reliable and less susceptible to manipulation or faking by the developer.

We found that employers looked for signals that provided evidence of active involvement in the open source community as authentic signals of passion for coding and indicators of a good fit with their organization.

They also looked for evidence that work had been accepted to well-known projects, because this type of third-party acceptance was not easy to fake. Connection to these high status projects increased employer perceptions of the candidate’s competence or quality.

Overall, the difficulty of accessing different cues also played a role; employers were more likely to seek out information that was not time consuming to evaluate.

Job seekers acknowledged that they could not easily give a false impression of their skills through the actual code they wrote, but they could try to influence information given off by their projects through downplaying them in the repository descriptions or adding more proper comments into the code.

Given that GitHub has relatively recently gained popularity as an employment tool, it is possible that future site members will be more conscious about managing their impressions for future employers.

The implications of our results extend beyond software development as work becomes increasingly digital.  Providing accessible, reliable traces of an individual’s work history may support more accurate impressions of unknown others. These impressions will shape decisions about recruiting, hiring and promotion in both traditional and new forms of organizations like Wikipedia or crowdsourcing.

For more, see our full paper, Activity Traces and Signals in Software Developer Recruitment and Hiring.
Jennifer Marlow, Carnegie Mellon University
Laura Dabbish, Carnegie Mellon University

About the author

Jennifer Marlow

PhD student at Carnegie Mellon's Human-Computer Interaction Institute. I research the impact of impression formation on collaboration and behavior in online peer production communities.

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  • Great post. I particularly like the framing of the Github activity profiles in terms of assessment signals that are costly to fake. In your interviews with employers and prospectives, did you dig up any signals that they wished they could get (or give) cheaply on a Github profile? For example, Github doesn’t have explicit endorsements, like LinkedIn does. Was that mentioned? Or anything else?

    Thanks again for the post, and I’m looking forward to the full talk at CSCW next week!

    • Thanks, and that’s a great question…we didn’t specifically focus on this issue, but it’s definitely worth considering ways in which something like this could be incorporated. Other sites besides GitHub (e.g. Coderwall) do offer an “endorsement” feature similar to LinkedIn, so it would be interesting to see what people think of this feature there…

  • A very timely piece. Lately, I’ve been hearing a lot about “GitHub is your resume.”

    I think reputation is going be a very hot topic. As more of our lives move online and move into the open online, we’ll be able to track reputation better, and thus use it more meaningfully. We’re going to have verifiable reputations not only for our credit history, but our coding ability, our responsiveness to email, our friendliness, EVERYTHING!

    You’re exactly right that it’s hard to fake a GitHub reputation – which is what makes it so valuable and such a good signal.

    • Indeed, and it goes beyond GitHub….there’s discussion about whether people should put their StackOverflow score on their resume! In any event, I hope my response to this post will help to build my reputation as a friendly person :)