The hiring market for software developers has been particularly choppy since the Covid-19 pandemic. There has been unprecedented developer churn, a crazy hiring spree, followed swiftly by a frenzy of layoffs. "It went from what I'll call normal, pre-pandemic, to wild in one direction, then wild in the opposite direction," says Adam Wolf, global head of engineering at Bloomberg.

Finding enough software talent during the boom times was one thing. Retaining it was another. But while some were riding the waves, others chose a more measured approach. "We didn't go bonkers on hiring, and we haven't done layoffs, we've continued hiring," says Wolf. Now sitting at 9,000 engineers, Bloomberg’s headcount in that area has grown by over 50% over the past five years. 

At Bloomberg, the secret sauce to developer retention has been a combination of factors: slow and steady growth, hybrid work, rigorously selecting the right candidates, and sustained effort to create a strikingly modern yet stable working culture.

Just play it cool

Over that period, Bloomberg has focused on steady growth. "We've never had a hyper-growth stage," says Wolf, who has been with Bloomberg for over 20 years since joining as a trainee. In fact, over half of his "training class" from 2004 are still with the company. "We're kind of a place where people join and stay, which is unusual in the tech space," he says. "That kind of environment where people are job jumping constantly is disruptive, culturally, to us."

That’s not to say there isn’t competition for candidates; Wolf just sees that as an opportunity to find the right candidates. In Wolf’s view, if a candidate has multiple job offers and selects yours over others, it indicates they are actually interested and will fit better into your culture than someone who is short on other options. “We want to hire people who are going to be a fit for the long term,” he says.

Learning why engineers exit a company is integral to staying competitive in the job market. "We're always in competition," says Wolf. "We're always focused on understanding why people are leaving and what we can do differently." Optimizing this requires keeping an eye on compensation, engagement, and on-the-job learning, he says.

More face time wins hearts

The pandemic shook the status quo and pushed most software engineering teams into remote working conditions. While some teams thrive in a remote-first situation, it's not for everyone. According to Wolf, the after-effects of fully remote work at Bloomberg have increased employee churn and a growing feeling of disconnection. 

"People were job jumping after like nine months," says Wolf. "There was a noticeable difference in terms of the connection to the company, to their teams, to the people they join with, for the people who came in before or after the pandemic, than the people who came in during."

Like many others, Bloomberg has looked to strike a balance with a hybrid model, mandating three days a week in the office for engineers. Balancing the benefits of remote with in-person work not only aids retention, says Wolf, but has complementary effects on collaboration and mentorship, which aids productivity for the team as a whole. "Software engineering is fundamentally a team sport," he says.

Adopt dynamics from open source

Bloomberg has picked up a lot of tactics from how open-source communities operate. One is an asynchronous-first working habit to meet the needs of teams distributed across offices in New York, San Francisco, London, and the rest of the world. 

Another practice they've borrowed from the open-source world is a request for comments (RFC) process, and bringing core contributors together periodically, akin to a summit or conference you would see in the open-source world.

However, you must strike a balance to enable these working processes effectively. For instance, an RFC is great for "adding a new interface for a new capability, or reviewing a design of the approach we want to take for replication or sharding," says Wolf. But they can also slow down the flow of daily pull requests.

Contribute back to open source

As a big consumer of open-source technologies, it’s important for Bloomberg to contribute back to the community. From funding small, "a-guy-in-Nebraska-style projects", to landing a patch in TypeScript, Bloomberg is actively contributing in various ways. "If we're going to be users of this, we should contribute to it," says Wolf. He views this not only as an ethical imperative but also as a strategic one. "I think it's important motivationally for our developers."

For Wolf, contributing to packages upstream when you require changes is a much more ethical (and strategic) approach than asking unpaid contributors to work for free, or forking a project and doing your own thing. 

"If I fork, now I can't upgrade very easily, I don't get to benefit from other contributions, I have a hard time taking in security patches," he says. But you have to get comfortable with some of these benefits being a long game. "The payoff there is not immediate."