The monorepo performance tax

When codebases reach a certain size, traditional build tools begin to fail. Compilation times stretch into hours, and developers spend significant portions of their day waiting for CI pipelines to finish. Google solved this problem internally with a tool called Blaze, which was later open-sourced as Bazel. Bazel is fast because it treats every build step as a hermetic unit that can be cached and run in parallel. However, Bazel is famously difficult to manage. To get the performance benefits, a team needs to maintain a cluster of remote execution servers and a globally distributed cache.

BuildBuddy is a startup that productizes this infrastructure. Founded in 2019 by Siggi Simonarson and Tyler Williams, the company is part of a small group of specialists focused on the "Bazel ecosystem." Based in Palo Alto, the team is composed of former Google engineers who understood that while Bazel was powerful, the operational overhead was a barrier for most startups and mid-market enterprises. BuildBuddy provides a managed version of the remote backend Bazel requires, effectively turning a complex infrastructure project into a plug-and-play service.

Caching and remote execution

The core of the BuildBuddy product is its Remote Execution (RBE) and Remote Caching services. When a developer runs a build, BuildBuddy checks its cache to see if the specific action has been performed before by anyone else on the team. If it has, the result is downloaded instantly. If not, the build can be offloaded to thousands of parallel cores in BuildBuddy’s cloud, rather than taxing the local developer machine. This setup is particularly important for Mac-based teams who need to build for Linux targets or vice versa, as BuildBuddy manages the cross-platform runners.

Beyond just the backend, the company provides a Build & Test UI that visualizes build results. This is a significant improvement over the raw terminal output Bazel provides. The UI allows developers to inspect which tests failed, why a specific action was not cached, and how long individual steps took. This observability is a core differentiator, as debugging Bazel builds without a visual tool is a common pain point for platform engineers.

Open core and market competition

BuildBuddy operates on an open-core model. A significant portion of their code is available on GitHub, allowing companies to self-host the basic version of the platform. Their revenue comes from enterprise features like SSO, SAML integration, and dedicated Mac runners. This approach has allowed them to gain traction within the open-source community, with their logo appearing alongside projects like RabbitMQ and Kibana.

In the market, BuildBuddy competes primarily with EngFlow, which was founded by one of the original Bazel creators. While EngFlow tends to target the largest enterprise customers with highly specialized needs, BuildBuddy has carved out a position by being more accessible to a broader range of teams through its free cloud tier and straightforward UI. As companies move toward larger monorepos and more complex software architectures, the demand for specialized build acceleration like BuildBuddy’s is likely to grow alongside the general developer productivity category.