Sussing out software bugs is often a time-consuming chore, as any developer will tell you. Unit tests — a technique by which segments of source code are tested individually, one by one — can suck up an entire day for every feature that requires three to four days of coding. Moreover, according to a recent survey commissioned by BMC and conducted by Forrester Research, the average time it takes to resolve an app issue is roughly a week, with more complicated problems taking an average of 10 days.

That frustrating cycle prompted engineer Edith Harbaugh and John Kodumal to cofound LaunchDarkly, an Oakland, California-based startup developing a toolset that enables developers to selectively seed features to users ahead of broad rollouts. It today announced that it’s raised $44 million in series C funding led by Bessemer Venture Partners’ Ethan Kurzweil, with contributions from existing investors Redpoint, Vertex Ventures, DFJ, and Uncork Capital.

The fresh financing comes after a $21 million series B round in December 2017, and brings LaunchDarkly’s total raised to $76 million. Kodumal, who serves as CTO, says it’ll be used to grow the company’s platform and acquire new customers. He added that LaunchDarkly’s customer base grew to over 700 worldwide this year, roughly five years after launch, and now includes Microsoft, BMW, IBM, Ryanair, GoDaddy, NBC, Sling, LogMeIn, Meetup, and Atlassian.

Image Credit: LaunchDarkly

“In the past year the LaunchDarkly platform has evolved both in scale … and capability — we’ve become a key piece of the puzzle for software teams practicing continuous delivery,” said Kodumal. “This latest funding will help us scale the platform even further to meet the growing demand we’re seeing in the market and build new functionality to help our customers deliver better software experiences to their customers.”

So how’s it work? Within LaunchDarkly’s dashboard, developers wrap new, unfinished code with “feature flags” that allow that code to be tested in a production environment but prevent it from making its way to most users. Once the flagged features have been finalized, a flick of a digital switch propagates up to “billions” of changes in less than 200 milliseconds, thanks to a two-layer, Fastly-powered content distribution network (CDN).

“The LaunchDarkly platform enabled BMW to go from 0-60 in one [release cycle],” said BMW Technology president and general manager Chuck Medhurst, a current customer. “The ability for BMW to test, develop and deploy variable feature sets across our premium brands, markets, and platforms results in delivering the optimal value to our customers.”

All flags are stored locally; LaunchDarkly’s relay proxy establishes a connection with a streaming API before proxying said connection to multiple clients, allowing multiple servers to connect to a local stream. It operates in one of two modes: multi-tenant, which lets devs store data on the cloud service of their choice, or single tenant, which operates on-premise as a private instance. Both are highly scalable — LaunchDarkly claims it handles more than 200 billion feature flags daily from 340,000 servers across over a million mobile devices and browsers worldwide.

Image Credit: LaunchDarkly

“Our goal is to help product development teams worldwide, from small teams to huge enterprises, to keep up with the speed of innovation while reducing risk,” said Harbaugh. “We believe the future is built on software, and the additional capital will allow us to impact the world of feature management further and meet the needs of our customers in delivering fast results and excellence to their own customers.”

LaunchDarkly’s feature tag framework, which supports a wide variety of programming languages and platforms including Android, iOS, Java, JavaScript, C++, C, Swift, Ruby, Python, .NET, Node, and React via bespoke software development kits (SDK), can be managed across environments and projects and validated with custom targeting rules. Developers can segment users based on percentages or attributes like app versions, and on the managerial side of things, internal per-team access controls to prevent devs (or teams) from editing code or deploying features they shouldn’t. (Admins can see who changed flags and when via an audit log.)

“The sheer speed of innovation today makes it more difficult than ever for enterprises to release product changes quickly and reliably,” Kurzweil said. “Having invested in developer platform companies for nearly a decade, it was instantly clear that LaunchDarkly has the product and market vision to be the central platform for feature management.”