Bazel Build Optimization

When to use this skill

Use Bazel Build Optimization when an AI agent needs a reusable SKILL.md workflow for this job: Optimize Bazel builds for large-scale monorepos. Use when configuring Bazel, implementing remote execution, or optimizing build performance for enterprise codebases.

When not to use it

Skip Bazel Build Optimization when the task is outside the coding category, or when a more specific skill in this directory already covers the same workflow with clearer triggers.

How to install

1. Personal install: create ~/.claude/skills/bazel-build-optimization/SKILL.md (and any bundled scripts) so Claude Code, Claude Desktop, and compatible agents can load it in every project.
2. Project install: commit the same folder at .claude/skills/bazel-build-optimization/ so teammates get the skill with the repo.
3. Restart the agent session after copying files so it re-scans the skills directory, then ask for the task in words that match the skill description.

Full install guide for Claude, Cursor, and Codex

What this skill does

# Bazel Build Optimization

Production patterns for Bazel in large-scale monorepos.

## When to Use This Skill

- Setting up Bazel for monorepos - Configuring remote caching/execution - Optimizing build times - Writing custom Bazel rules - Debugging build issues - Migrating to Bazel

## Core Concepts

### 1. Bazel Architecture

``` workspace/ ├── WORKSPACE.bazel # External dependencies ├── .bazelrc # Build configurations ├── .bazelversion # Bazel version ├── BUILD.bazel # Root build file ├── apps/ │ └── web/ │ └── BUILD.bazel ├── libs/ │ └── utils/ │ └── BUILD.bazel └── tools/ └── bazel/ └── rules/ ```

### 2. Key Concepts

| Concept | Description | | ----------- | -------------------------------------- | | **Target** | Buildable unit (library, binary, test) | | **Package** | Directory with BUILD file | | **Label** | Target identifier `//path/to:target` | | **Rule** | Defines how to build a target | | **Aspect** | Cross-cutting build behavior |

## Templates and detailed worked examples

Full template library and detailed worked examples live in `references/details.md`. Read that file when you need the concrete templates.

## Best Practices

### Do's

- **Use fine-grained targets** - Better caching - **Pin dependencies** - Reproducible builds - **Enable remote caching** - Share build artifacts - **Use visibility wisely** - Enforce architecture - **Write BUILD files per directory** - Standard convention

### Don'ts

- **Don't use glob for deps** - Explicit is better - **Don't commit bazel-\* dirs** - Add to .gitignore - **Don't skip WORKSPACE setup** - Foundation of build - **Don't ignore build warnings** - Technical debt

Intended uses

• Setting up Bazel for monorepos
• Configuring remote caching/execution
• Optimizing build times
• Writing custom Bazel rules
• Debugging build issues
• Migrating to Bazel