BAZEL_TRAINING.MD

Bazel Training

The list of learning resources, Q&A notes, random links

Curated Bazel Reading List

Bazel 101

• Build Basics
  • Why a Build System?
  • Task-Based Build Systems
  • Artifact-Based Build Systems
  • Distributed Builds
  • Dependency Management
  • Hermeticity
• Bazel Vision
• Why Bazel?
• Workspaces, packages, and targets
• Labels
• BUILD files
• Dependencies
• Visibility
• External Dependencies
• Phases of a build
• Building with Bazel Note: Do not try to read the entire page. Focus on deep linked sections.
  • Available commands
  • Q.What is in the build? A. Run “bazel query …”
  • Building one target
  • Building multiple targets
  • Command line reference - The list is massive, but is systematic. No need to get familiar with every option, just the way the command line is organized.
• Practice:
  • Build a Java Project or Build a C++ Project

Bazel 201 - Custom Rules

• Starlark Language
• Macros and Rules
• Macros Reference
• Rules Reference
  • Rule creation
  • Target instantiation
  • Attributes
  • Output attributes
  • Targets
  • Files
  • Declaring outputs
  • Actions
  • Providers
  • Runfiles & Runfiles symlinks
  • Executable rules and test rules
• Depsets
• Repository Rules
• Using Macros to Create Custom Verbs
• Testing Rules
• Practice:
  • Create a rule
  • Rules examples repository

Bazel 202 - Language-specific rules

• JavaScript
  • rules_js - pnpm support
  • rules_ts - TypeScript
  • rules_swc - swc
  • rules_esbuild - esbuild
  • rules_webpack - Webpack
  • rules_webtesting
• C++ to WASM: emsdk
• macOS/iOS:
  • rules_apple
  • rules_ios
  • rules_xcodeproj
• Go: rules_go
• Python: rules_python
• Practice:
  • Hello World (C++ to WASM/JS)
  • Next.js Example

Bazel 203 - Packaging rules

• Tar, Zip, Deb, PRM: rules_pkg
• Containers: rules_docker
• Kubernetes & GitOps: rules_gitops

Bazel 302 - In depth topics

• Correct incremental rebuilds
• The Bazel Query Reference
• Action Graph Query (aquery)
• Fetching external dependencies
• Bazel Caching Explained
  • How Bazel Works
  • Bazel In-Memory Cache
  • Repository Cache
  • Persistent Action Cache
• How does Bazel track local resource usage?
• Remote Caching
• Remote Caching and Remote Execution Explained
• Debugging Remote Cache Hits
• Debugging Remote Cache Hits for Local Execution
• Test encyclopedia
• Performance profiling
• Memory profiling
• Analyzing Build Performance (blog)
• —subcommands command line parameter
• Output Directory Layout

Bazel 401 - Multi Platform Builds

• Building with Platforms
• Platforms Reference
• Toolchains Reference
• Configurations Reference
• Configurable Attributes Reference
• Configurable Query (cquery)
• Bazel Platforms Cookbook
  • Hello World - How and when do I use platforms + constraints?
  • Using different platforms
  • How do I specify that some library cannot target e.g. Windows?
  • On a library, I want to say needs java > 1.8, how?
  • How do I match multiple config settings at once?
  • How do I express that haswell cpu also implies SSE3 availability?.
  • How and when do I use --define?
  • How and when should I use build_setting?

Bazel 402 - Persistent workers

• Persistent Workers
• What are Bazel's strategies?
• Creating Persistent Workers
• Multiplex Workers