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·Brandon Duffany

BuildBuddy MCP server

BuildBuddy now exposes an MCP endpoint for coding agents and other MCP-capable clients.

MCP provides a way to let agents explore BuildBuddy data for mostly read-only workflows like build and test metadata, logs, artifacts, target statuses, and more.

You can connect agents like Codex, Claude Code, and Gemini CLI to:

https://YOUR-BUILDBUDDY-ORGANIZATION.buildbuddy.io/mcp

Authenticate with:

Authorization: Bearer <api-key>

See the new BuildBuddy MCP Server docs for setup instructions and configuration examples.

·Dan Stowell

Improved handling of short-lived secrets in remote execution

BuildBuddy has supported passing short-lived secrets to remote actions via the env-overrides platform property, which redacts values from action cache entries. The new secret-env-overrides and secret-env-overrides-base64 properties extend this protection by also redacting values from workflow logs.

Pass secrets via remote exec headers so they're injected at invocation time without affecting the action hash:

bazel build //my:target \
  --remote_exec_header=x-buildbuddy-platform.secret-env-overrides=API_KEY=sk-abc123,OTHER_KEY=val

For values containing commas or special characters, base64-encode each KEY=VALUE pair:

bazel build //my:target \
  --remote_exec_header=x-buildbuddy-platform.secret-env-overrides-base64=$(echo -n 'CREDS={"token": "abc"}' | base64)

See the Secrets docs and RBE platform properties reference for more details.

bazel
·Maggie Lou

Changelog

We're excited to introduce the BuildBuddy Changelog!

We're a team of builders, but we historically haven't always made noise about the features we've built. This changelog is where we'll highlight feature launches and meaningful infrastructure improvements.

To get started, we're sharing some high-impact features from the past few years that teams may have missed.

·Tyler French

Dark mode

We're excited to announce dark mode for our UI.

To enable, go to Settings then Preferences under Personal Settings.

·Fabian Meumertzheim

bb explain: understand why your build re-ran actions

bb explain shows a structural diff of two compact execution logs. It helps answer the common questions: "Why did Bazel re-execute that action?" and "What changed between these builds?"

bb explain

It can highlight non-hermetic outputs and differences in inputs, environment variables, and arguments.

It works with your last two builds automatically, or you can point it at any invocation IDs:

bb explain
bb explain --old <OLD_INVOCATION_ID> --new <NEW_INVOCATION_ID>

You can download the bb CLI here. More details in Fabian's BazelCon talk.

bazeldebuggingfeatured
·Jim Hollenbach

Drilldowns: find similarities between slow or failing builds

The drilldown view displays heatmaps of build and execution metrics over time. It can help isolate why a subset of builds is slower or failing more often.

You can select a region of outliers on the heatmap, and Drilldowns will compare that selection against the baseline across dimensions like branch, pattern, and tag.

This makes it easier to spot common characteristics of problematic builds.

Available on the sidebar under Drilldowns.

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·Siggi Simonarson

Compare invocations: compare two builds side-by-side

The compare invocations view allows you to diff two invocations side-by-side.

It can help debug why two builds produced different results by showing exactly what changed: different flags, startup options, cache/remote execution settings, status, and more.

To compare invocations:

  1. From one invocation link, select Compare -> Select for comparison in the top right corner.
  2. From another invocation link, select Compare -> Compare with selected.
  3. For even more details on differences between the two invocations, click the Run bb explain button on the compare invocations page.
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·Siggi Simonarson

Compare actions: compare two actions side-by-side

The compare actions view allows you to diff two actions side-by-side.

This can help pinpoint why two seemingly similar actions produced different results or didn't result in a cache hit.

To compare actions:

  1. From an invocation link, you can find the desired action either in the Cache or Remote Execution tabs.
  2. Click through to the Action Details view.
  3. Click Compare -> Select for comparison in the top right corner.
  4. Find the other action you want to compare it against.
  5. Click Compare -> Compare with selected in the top right corner of the second action.
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