/bazel-build-optimization

name: bazel-build-optimization
description: Optimize Bazel builds for large-scale monorepos. Use when configuring Bazel, implementing remote execution, or optimizing build performance for enterprise codebases.

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