Investing in EngFlow

Build is one of the most foundational tools for software engineering. Traditionally, it is the step in software development that takes the files written by engineers and compiles them into machine runnable code, but build has become so much more. Yes, it is used to compile code, but it is often the start of the developer workflow, from orchestrating application tooling, testing, environment setup, security, and compliance testing to even deployment. It really has become the central nervous system to development. 

At a16z, we’ve been tracking build systems closely for years because it plays such a key role in software. However, build tools have been a fragmented market, with a particular build system most commonly used with a given language. For example, Java developers were likely to use a different tool than, say, C developers. 

All of this changed when Google open sourced Bazel, which has since become a leading build system industry-wide. Bazel is an incredibly powerful build system that is fast, multi-language, extensible, and tremendously powerful. Over the last few years we’ve seen it take off rapidly in the industry, with adoption by many of the most sophisticated software companies. 

Therefore, we were overjoyed when we learned that two of the core Bazel team, Helen Altshuler and Ulf Adams, had left to found EngFlow, the Bazel company. Early into our first meeting, we were fully sold on the team. Ulf, who is CTO, is one of the creators of Bazel and also one of the most respected engineers we’ve ever spoken to. And Helen, who is CEO, has an incredibly impressive background as a tech leader and has been integral to the Bazel community, where she led the adoption of the open source project and has deep relationships with everyone involved and on the periphery. Beyond that, they’ve put together the highest density of build and Bazel experts we’ve ever seen, with 70 percent of the company being from the original Bazel team and open source contributors. 

We’re very excited to announce that we’ve joined the EngFlow team and led their seed round. Helen and Ulf are exactly the type of founders we love to back, and EngFlow — which is based on a leading, open, and deeply technical project and is delivering Bazel solutions to the enterprise — is exactly the type of company we love to be involved in. Since we made the investment, I’ve had the pleasure of watching the company’s development over the last few months, and EngFlow is already engaged with many top software companies as paying customers, including Snap and Brave. It’s almost as if this seedling was birthed as a full adult! 

EngFlow’s solution is not limited to Bazel. While we strongly believe Bazel is the best build system out there, the EngFlow team is the best build team on the planet, and they are building the best platform independent build solution. They already support Soong/AOSP and Chromium/Goma today, and have support for many other build platforms on the roadmap. 

So, if you’re a Bazel user, you really need to speak with EngFlow. More broadly, if build times, build costs, and the flexibility of your build system — regardless of what it’s currently based on — are important to you, then you really should be speaking with EngFlow.  


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