BuildBuddy is an open source Bazel build event viewer. It helps you collect, view, share and debug build events in a user-friendly web UI.

It’s written in Golang and React and can be deployed as a Docker image. It’s run both as a cloud hosted service and can be deployed to your cloud provider or run on-prem. BuildBuddy’s core is open sourced in this repo under the MIT License.

Get started

Getting started with BuildBuddy is easy - check out our getting started guide.


  • Build summary & logs - a high level overview of the build including who initiated the build, how long it took, how many targets were affected, etc. The build log makes it easy to share stack traces and errors with teammates which makes collaborative debugging easier. Build summary & logs
  • Target overview - quickly see which targets and tests passed / failed and dig into more details about them. Target overview
  • Detailed timing information - BuildBuddy invocations include a “Timing” tab - which pulls the Bazel profile logs from your build cache and displays them in a human-readable format. Detailed timing information
  • Invocation details - see all of the explicit flags, implicit options, and environment variables that affect your build. This is particularly useful when a build is working on one machine but not another - you can compare these and see what’s different. Invocation details
  • Build artifacts - get a quick view of all of the build artifacts that were generated by this invocation so you can easily access them. Clicking on build artifacts downloads the artifact when using either the built-in BuildBuddy cache, or a third-party cache running in GRPC mode that supports the bytestream API - like bazel-remote. Artifacts
  • Raw logs - you can really dig into the details here. This is a complete view of all of the events that get sent up via Bazel’s build event protocol. If you find yourself digging in here too much, let us know and we’ll surface that info in a nicer UI. Raw logs
  • Remote cache support - BuildBuddy comes with an optional built-in Bazel remote cache to BuildBuddy, implementing the GRPC remote caching APIs. This allows BuildBuddy to optionally collect build artifacts, timing profile information, test logs, and more. Alternatively, BuildBuddy supports third-party caches running in GRPC mode that support the bytestream API - like bazel-remote.
  • Viewable test logs - BuildBuddy surfaces test logs directly in the UI when you click on a test target (GRPC remote cache required). Viewable test logs
  • Dense UI mode - if you want more information density, BuildBuddy has a “Dense mode” that packs more information into every square inch. Dense UI mode
  • BES backend multiplexing - if you’re already pointing your bes_backend flag at another service. BuildBuddy has a build_event_proxy configuration option that allows you to specify other backends that your build events should be forwarded to. See the configuration docs for more information. BES backend multiplexing
  • Slack webhook support - BuildBuddy allows you to message a Slack channel when builds finish. It’s a nice way of getting a quick notification when a long running build completes, or a CI build fails. See the configuration docs for more information. Slack webhook support


If you have any questions, e-mail us at We’d love to chat!