workspace/

Ôö£ÔöÇÔöÇ WORKSPACE.bazel # External dependencies

Ôö£ÔöÇÔöÇ .bazelrc # Build configurations

Ôö£ÔöÇÔöÇ .bazelversion # Bazel version

Ôö£ÔöÇÔöÇ BUILD.bazel # Root build file

Ôö£ÔöÇÔöÇ apps/

Ôöé ÔööÔöÇÔöÇ web/

Ôöé ÔööÔöÇÔöÇ BUILD.bazel

Ôö£ÔöÇÔöÇ libs/

Ôöé ÔööÔöÇÔöÇ utils/

Ôöé ÔööÔöÇÔöÇ BUILD.bazel

ÔööÔöÇÔöÇ tools/

ÔööÔöÇÔöÇ bazel/

ÔööÔöÇÔöÇ rules/

2. Key Concepts

| Concept | Description |

|---------|-------------|

| Target | Buildable unit (library, binary, test) |

| Package | Directory with BUILD file |

| Rule | Defines how to build a target |

| Aspect | Cross-cutting build behavior |

Templates

Template 1: WORKSPACE Configuration

WORKSPACE.bazel

workspace(name = "myproject")

load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")

Rules for JavaScript/TypeScript

http_archive(

name = "aspect_rules_js",

sha256 = "...",

strip_prefix = "rules_js-1.34.0",

url = "https://github.com/aspect-build/rules_js/releases/download/v1.34.0/rules_js-v1.34.0.tar.gz",

)

load("@aspect_rules_js//js:repositories.bzl", "rules_js_dependencies")

rules_js_dependencies()

load("@rules_nodejs//nodejs:repositories.bzl", "nodejs_register_toolchains")

nodejs_register_toolchains(

name = "nodejs",

node_version = "20.9.0",

)

load("@aspect_rules_js//npm:repositories.bzl", "npm_translate_lock")

npm_translate_lock(

name = "npm",

pnpm_lock = "//:pnpm-lock.yaml",

verify_node_modules_ignored = "//:.bazelignore",

)

load("@npm//:repositories.bzl", "npm_repositories")

npm_repositories()

Rules for Python

http_archive(

name = "rules_python",

sha256 = "...",

strip_prefix = "rules_python-0.27.0",

url = "https://github.com/bazelbuild/rules_python/releases/download/0.27.0/rules_python-0.27.0.tar.gz",

)

load("@rules_python//python:repositories.bzl", "py_repositories")

py_repositories()

Template 2: .bazelrc Configuration

.bazelrc

Build settings

build --enable_platform_specific_config

build --incompatible_enable_cc_toolchain_resolution

build --experimental_strict_conflict_checks

Performance

build --jobs=auto

build --local_cpu_resources=HOST_CPUS*.75

build --local_ram_resources=HOST_RAM*.75

Caching

build --disk_cache=~/.cache/bazel-disk

build --repository_cache=~/.cache/bazel-repo

Remote caching (optional)

build:remote-cache --remote_cache=grpcs://cache.example.com

build:remote-cache --remote_upload_local_results=true

build:remote-cache --remote_timeout=3600

Remote execution (optional)

build:remote-exec --remote_executor=grpcs://remote.example.com

build:remote-exec --remote_instance_name=projects/myproject/instances/default

build:remote-exec --jobs=500

Platform configurations

build:linux --platforms=//platforms:linux_x86_64

build:macos --platforms=//platforms:macos_arm64

CI configuration

build:ci --config=remote-cache

build:ci --build_metadata=ROLE=CI

build:ci --bes_results_url=https://results.example.com/invocation/

build:ci --bes_backend=grpcs://bes.example.com

Test settings

test --test_output=errors

test --test_summary=detailed

Coverage

coverage --combined_report=lcov

coverage --instrumentation_filter="//..."

Convenience aliases

build:opt --compilation_mode=opt

build:dbg --compilation_mode=dbg

Import user settings

try-import %workspace%/user.bazelrc

Template 3: TypeScript Library BUILD

libs/utils/BUILD.bazel

load("@aspect_rules_ts//ts:defs.bzl", "ts_project")

load("@aspect_rules_js//js:defs.bzl", "js_library")

load("@npm//:defs.bzl", "npm_link_all_packages")

npm_link_all_packages(name = "node_modules")

ts_project(

name = "utils_ts",

srcs = glob(["src/**/*.ts"]),

declaration = True,

source_map = True,

tsconfig = "//:tsconfig.json",

deps = [

":node_modules/@types/node",

],

)

js_library(

name = "utils",

srcs = [":utils_ts"],

visibility = ["//visibility:public"],

)

Tests

load("@aspect_rules_jest//jest:defs.bzl", "jest_test")

jest_test(

name = "utils_test",

config = "//:jest.config.js",

data = [

":utils",

"//:node_modules/jest",

],

node_modules = "//:node_modules",

)

Template 4: Python Library BUILD

libs/ml/BUILD.bazel

load("@rules_python//python:defs.bzl", "py_library", "py_test", "py_binary")

load("@pip//:requirements.bzl", "requirement")

py_library(

name = "ml",

srcs = glob(["src/**/*.py"]),

deps = [

requirement("numpy"),

requirement("pandas"),

requirement("scikit-learn"),

"//libs/utils:utils_py",

],

visibility = ["//visibility:public"],

)

py_test(

name = "ml_test",

srcs = glob(["tests/**/*.py"]),

deps = [

":ml",

requirement("pytest"),

],

size = "medium",

timeout = "moderate",

)

py_binary(

name = "train",

srcs = ["train.py"],

deps = [":ml"],

data = ["//data:training_data"],

)

Template 5: Custom Rule for Docker

tools/bazel/rules/docker.bzl

def _docker_image_impl(ctx):

dockerfile = ctx.file.dockerfile

base_image = ctx.attr.base_image

layers = ctx.files.layers

# Build the image

output = ctx.actions.declare_file(ctx.attr.name + ".tar")

args = ctx.actions.args()

args.add("--dockerfile", dockerfile)

args.add("--output", output)

args.add("--base", base_image)

args.add_all("--layer", layers)

ctx.actions.run(

inputs = [dockerfile] + layers,

outputs = [output],

executable = ctx.executable._builder,

arguments = [args],

mnemonic = "DockerBuild",

progress_message = "Building Docker image %s" % ctx.label,

)

return [DefaultInfo(files = depset([output]))]

docker_image = rule(

implementation = _docker_image_impl,

attrs = {

"dockerfile": attr.label(

allow_single_file = [".dockerfile", "Dockerfile"],

mandatory = True,

),

"base_image": attr.string(mandatory = True),

"layers": attr.label_list(allow_files = True),

"_builder": attr.label(

default = "//tools/docker:builder",

executable = True,

cfg = "exec",

),

},

)

Template 6: Query and Dependency Analysis

Find all dependencies of a target

bazel query "deps(//apps/web:web)"

Find reverse dependencies (what depends on this)

bazel query "rdeps(//..., //libs/utils:utils)"

Find all targets in a package

bazel query "//libs/..."

Find changed targets since commit

bazel query "rdeps(//..., set($(git diff --name-only HEAD~1 | sed 's/.*/"&"/' | tr '\n' ' ')))"

Generate dependency graph

bazel query "deps(//apps/web:web)" --output=graph | dot -Tpng > deps.png

Find all test targets

bazel query "kind('.*_test', //...)"

Find targets with specific tag

bazel query "attr(tags, 'integration', //...)"

Compute build graph size

bazel query "deps(//...)" --output=package | wc -l

Template 7: Remote Execution Setup

platforms/BUILD.bazel

platform(

name = "linux_x86_64",

constraint_values = [

"@platforms//os:linux",

"@platforms//cpu:x86_64",

],

exec_properties = {

"container-image": "docker://gcr.io/myproject/bazel-worker:latest",

"OSFamily": "Linux",

},

)

platform(

name = "remote_linux",

parents = [":linux_x86_64"],

exec_properties = {

"Pool": "default",

"dockerNetwork": "standard",

},

)

toolchains/BUILD.bazel

toolchain(

name = "cc_toolchain_linux",

exec_compatible_with = [

"@platforms//os:linux",

"@platforms//cpu:x86_64",

],

target_compatible_with = [

"@platforms//os:linux",

"@platforms//cpu:x86_64",

],

toolchain = "@remotejdk11_linux//:jdk",

toolchain_type = "@bazel_tools//tools/jdk:runtime_toolchain_type",

)

Performance Optimization

Profile build

bazel build //... --profile=profile.json

bazel analyze-profile profile.json

Identify slow actions

bazel build //... --execution_log_json_file=exec_log.json

Memory profiling

bazel build //... --memory_profile=memory.json

Skip analysis cache

bazel build //... --notrack_incremental_state