Stack Overflow is a Q&A site where programmers, software engineers and other tech pros discuss everything from Unix and SharePoint to photography, math and role-playing games. It’s the kind of place where users explore technical topics as granular as “No Response from jQuery getJSON method” and “Request params not parsed in Ring/Compojure app.”
Like GitHub, it’s primarily used to pursue the successful implementation of technology. Users ask questions when they’ve hit a wall in their approach and have exhausted all of the possible solutions they could uncover on their own. The difference between the two is that, on GitHub, users primarily post and comment on code, whereas on Stack Overflow they engage in detailed conversations about often-narrow aspects of technical challenges.
For recruiters, Stack Overflow represents an opportunity to get a sense of a candidate’s technical expertise, how they approach challenges, and their skill at communicating with others. Many say its tools are too limited for conducting effective searches, but most agree the site can provide meaningful information that will help you decide whether a candidate has the skills and personality to fit with the specific demands of a particular opening.
“We’re localized and Stack Overflow isn’t set up for local searches,” said Willis Johnson, Vice President of Technical Recruiting for the Robert Half Technology office in Albuquerque, N.M. “But I use it as another tool to vet candidates—see how they interact, what questions they ask, look at the bits of code they post, see how their logic works.”
Johnson also noted that a “true programmer” will be on either Stack Overflow or GitHub: “If not, it’s a red flag.”
Aaron Ho, a recruiter at San Francisco-based Riviera Partners, says the site is a good way to get a sense of a candidate’s expertise. One of the first things he does is look at the “reputation” score that’s featured on each user’s profile. The higher the score, the more active the user and the more answers they’ve provided that others thought were helpful.
In addition, examining a user’s “Top Tags” and “Top Posts” provides an idea of where the user has the most expertise. “The assumption is that if they are taking the time to answer specific types of questions, and other people are upvoting them, then they are probably pretty good at it,” Ho said.
Johnson points out that even a user’s questions provide an indication of their work habits. “One ‘rule’ of Stack Overflow is that you’re supposed to try to answer the question yourself,” he said. He’s wary of users who post a simple question without any indication that they’ve already spent time trying to work a problem through. Those people, he believes, “are trying to get other people to do the work for them.”
Using Stack Overflow does have its downsides, however. Because of its Q&A format, it can be more hit-or-miss than GitHub in providing access to a user’s work samples. In addition, said Scott Schefferstein, Senior Technical Recruiter in the New Orleans office of the consulting firm Resolvit, some engineers simply don’t warm up to the site’s approach. “Some of the best developers I know, you wouldn’t be impressed by their Stack Overflow profiles at all,” he said.
Ho agrees. Though he “absolutely” uses it to vet candidates he finds from other sources, “you have to take it with a grain of salt,” he said. “Just because an engineer doesn’t have a fully built out Stack Overflow profile, doesn’t have a high Reputation score, or hasn’t answered many questions, it doesn’t mean he’s a bad engineer.”
Likewise, he continued, “Just because an engineer answers a lot of questions, it doesn’t automatically mean he is good at programming. You have to take a look at the content of the answers and how well they were received by the community.”
“GitHub and Stack Overflow are like Twitter and Facebook,” Johnson added. “Many try both, but then tend to stick to one or the other. Typically, they’re two very different types of users.”
Stack Overflow differs from GitHub, in that it hosts more interaction between users, said Johnson. Right off the bat, that hints that Stack Overflow users are less introverted, and helps him get a sense of how they’d work on a team and approach other people. “You can learn a lot about temperament and logic,” he said.
Even though he doesn’t use Stack Overflow regularly, Schefferstein agreed that you could get a lot out of reading their answers. When a user goes into depth, “that tells me something. Someone who’s glib tells me something else. Read a few of their posts and you can get a sense of them.” That, he added, “can be helpful in terms of figuring out how to approach them.”
When to Tread Carefully
Using Stack Overflow isn’t without its dangers, recruiters suggest. First among them: It’s a professional community hosting professional conversations. A sure way to burn your bridges is to spam threads with job pitches. “I’d caution about interacting with developers on Stack Overflow,” said Johnson. “We’re recruiters, not developers. When non-tech people try to interact, our answers tend not to be very good. It’s not a communications tool.”
That said, Johnson noted that he has occasionally posted queries asking what would be good interview questions for certain skill sets. In each case, he received valuable answers.
The other danger is relying on it too much. As Schefferstein pointed out, some talented engineers just don’t take advantage of Stack Overflow, and Johnson says it would obviously prove detrimental to use it as your only vetting tool: “There are so many other things that go into recruiting a candidate.”
If you’re not using Stack Overflow, Ho recommends giving it a try. “It does take a little bit more time and effort to locate the right candidates, but it’s definitely worth it,” he said. Johnson adds that the site has a “very good, robust” help section, and suggests: “Just go in and get acclimated. Pick some topics you’re recruiting on and go take a look.”