Bazel

aid: bazel-build
name: Bazel
description: Bazel is a fast, scalable, multi-language and extensible build tool open-sourced by Google. It supports
  software projects of any size across Java, C++, Go, Python, Rust, Swift, Kotlin, Scala, Android, iOS, and many other
  languages and platforms. Bazel uses a hermetic, sandboxed execution model with content-addressable caching, parallel
  builds, and remote execution. The project ships the `bazel` CLI, the Starlark extension language for build rules, the
  MODULE.bazel external-dependency system (Bzlmod), and the Bazel Central Registry — a public HTTP index registry that
  hosts community-maintained Bazel modules.
type: Index
position: Consumer
access: 3rd-Party
image: https://kinlane-productions.s3.amazonaws.com/apis-json/apis-json-logo.jpg
tags:
- Build Systems
- Build Tool
- Bzlmod
- CI/CD
- Developer Tools
- Hermetic Builds
- Monorepo
- Open Source
- Remote Execution
- Starlark
created: '2026-05-25'
modified: '2026-05-25'
url: https://raw.githubusercontent.com/api-evangelist/bazel-build/refs/heads/main/apis.yml
specificationVersion: '0.19'
apis:
- aid: bazel-build:bazel-central-registry-api
  name: Bazel Central Registry API
  description: The Bazel Central Registry (BCR) is the default index registry consulted by Bzlmod, Bazel's external
    dependency management system. The BCR exposes a stable HTTP layout at https://bcr.bazel.build/ that serves a
    registry-wide bazel_registry.json plus per-module metadata.json, MODULE.bazel manifests, and source.json fetch
    instructions. Since Bazel 8 Bzlmod is on by default, making the BCR the registry every Bazel install resolves
    against unless --registry is overridden.
  humanURL: https://registry.bazel.build/
  baseURL: https://bcr.bazel.build
  tags:
  - Bzlmod
  - Index Registry
  - Modules
  - Package Registry
  properties:
  - type: Documentation
    url: https://bazel.build/external/registry
  - type: Documentation
    url: https://bazel.build/external/module
  - type: Portal
    url: https://registry.bazel.build/
  - type: OpenAPI
    url: openapi/bazel-central-registry-openapi.yml
  - type: JSONSchema
    url: json-schema/bcr-bazel-registry-schema.json
  - type: JSONSchema
    url: json-schema/bcr-metadata-schema.json
  - type: JSONSchema
    url: json-schema/bcr-source-schema.json
  - type: GitHubRepository
    url: https://github.com/bazelbuild/bazel-central-registry
- aid: bazel-build:bazel-cli
  name: Bazel Command Line Interface
  description: The `bazel` command line tool is the primary user-facing surface of Bazel. It exposes commands such as
    `build`, `test`, `run`, `query`, `cquery`, `aquery`, `mod`, `fetch`, `info`, `coverage`, and `clean`, plus the
    BEP/BES streaming protocols for build event publishing. Bazelisk is the recommended launcher that pins the Bazel
    version per project via .bazelversion.
  humanURL: https://bazel.build/reference/command-line-reference
  tags:
  - CLI
  - Commands
  - Tooling
  properties:
  - type: Documentation
    url: https://bazel.build/reference/command-line-reference
  - type: Documentation
    url: https://bazel.build/run/build
  - type: Documentation
    url: https://bazel.build/query/language
  - type: Tool
    url: https://github.com/bazelbuild/bazel
  - type: Tool
    url: https://github.com/bazelbuild/bazelisk
- aid: bazel-build:bazel-starlark-api
  name: Bazel Starlark Build API
  description: Bazel's build rules, macros, and module extensions are written in Starlark — a deterministic Python
    dialect. The Starlark Build API exposes the rule(), repository_rule(), module_extension(), aspect(), and provider()
    primitives used to declare build targets, generate actions, and integrate new languages. BUILD, BUILD.bazel,
    .bzl, MODULE.bazel, and WORKSPACE files are all evaluated by this API.
  humanURL: https://bazel.build/rules
  tags:
  - BUILD
  - DSL
  - Extension
  - Rules
  - Starlark
  properties:
  - type: Documentation
    url: https://bazel.build/rules
  - type: Documentation
    url: https://bazel.build/rules/language
  - type: Documentation
    url: https://bazel.build/extending/concepts
  - type: APIReference
    url: https://bazel.build/rules/lib/starlark-overview
- aid: bazel-build:bazel-remote-execution-api
  name: Bazel Remote Execution API
  description: Bazel speaks the open Remote Execution API (REAPI), a gRPC protocol for content-addressable storage and
    distributed action execution. REAPI lets Bazel offload compile, test, and link actions to a remote build farm and
    share a Content-Addressable Store (CAS) and Action Cache across users and CI runners. Bazel implements the
    client side; servers such as BuildBuddy, EngFlow, Buildbarn, Buildfarm, and Google RBE implement the server side.
  humanURL: https://github.com/bazelbuild/remote-apis
  tags:
  - CAS
  - Caching
  - Distributed Builds
  - gRPC
  - Remote Execution
  properties:
  - type: Documentation
    url: https://bazel.build/remote/rbe
  - type: Documentation
    url: https://bazel.build/remote/caching
  - type: GitHubRepository
    url: https://github.com/bazelbuild/remote-apis
  - type: ProtocolBuffer
    url: https://github.com/bazelbuild/remote-apis/blob/main/build/bazel/remote/execution/v2/remote_execution.proto
- aid: bazel-build:bazel-build-event-protocol
  name: Bazel Build Event Protocol
  description: The Build Event Protocol (BEP) is Bazel's structured stream of build events — target configured,
    progress, test results, action executed, build finished — emitted during every invocation. BEP can be written to a
    local file (--build_event_json_file / --build_event_binary_file) or streamed via gRPC to a Build Event Service
    (BES) backend for build observability, flake analysis, and CI dashboards.
  humanURL: https://bazel.build/remote/bep
  tags:
  - BEP
  - BES
  - Build Events
  - Observability
  - Streaming
  properties:
  - type: Documentation
    url: https://bazel.build/remote/bep
  - type: Documentation
    url: https://bazel.build/remote/bep-examples
  - type: ProtocolBuffer
    url: https://github.com/bazelbuild/bazel/blob/master/src/main/java/com/google/devtools/build/lib/buildeventstream/proto/build_event_stream.proto
common:
- type: Portal
  url: https://bazel.build/
- type: Documentation
  url: https://bazel.build/docs
- type: GettingStarted
  url: https://bazel.build/start
- type: APIReference
  url: https://bazel.build/reference
- type: Blog
  url: https://blog.bazel.build/
- type: GitHubOrganization
  url: https://github.com/bazelbuild
- type: GitHubRepository
  url: https://github.com/bazelbuild/bazel
- type: GitHubRepository
  url: https://github.com/bazelbuild/bazel-central-registry
- type: GitHubRepository
  url: https://github.com/bazelbuild/bazelisk
- type: GitHubRepository
  url: https://github.com/bazelbuild/buildtools
- type: GitHubRepository
  url: https://github.com/bazelbuild/bazel-gazelle
- type: GitHubRepository
  url: https://github.com/bazelbuild/bazel-skylib
- type: GitHubRepository
  url: https://github.com/bazelbuild/remote-apis
- type: ChangeLog
  url: https://github.com/bazelbuild/bazel/releases
- type: Issues
  url: https://github.com/bazelbuild/bazel/issues
- type: Roadmap
  url: https://bazel.build/about/roadmap
- type: Governance
  url: https://bazel.build/contribute/contribution-policy
- type: TermsOfService
  url: https://github.com/bazelbuild/bazel/blob/master/LICENSE
- type: Security
  url: https://bazel.build/about/security
- type: Forum
  url: https://slack.bazel.build/
- type: StackOverflow
  url: https://stackoverflow.com/questions/tagged/bazel
- type: Tool
  url: https://github.com/bazelbuild/bazelisk
  name: Bazelisk (Bazel version launcher)
- type: Tool
  url: https://github.com/bazelbuild/buildtools
  name: Buildifier, Buildozer, Unused_deps formatters
- type: Tool
  url: https://github.com/bazelbuild/bazel-gazelle
  name: Gazelle BUILD file generator
- type: SDK
  url: https://github.com/bazelbuild/rules_java
  name: rules_java
- type: SDK
  url: https://github.com/bazelbuild/rules_cc
  name: rules_cc
- type: SDK
  url: https://github.com/bazelbuild/rules_python
  name: rules_python
- type: SDK
  url: https://github.com/bazelbuild/rules_go
  name: rules_go
- type: SDK
  url: https://github.com/bazelbuild/rules_rust
  name: rules_rust
- type: SDK
  url: https://github.com/bazelbuild/rules_swift
  name: rules_swift
- type: SDK
  url: https://github.com/bazelbuild/rules_apple
  name: rules_apple
- type: SDK
  url: https://github.com/bazelbuild/rules_kotlin
  name: rules_kotlin
- type: SDK
  url: https://github.com/bazelbuild/rules_scala
  name: rules_scala
- type: SDK
  url: https://github.com/bazelbuild/rules_nodejs
  name: rules_nodejs
- type: SDK
  url: https://github.com/bazelbuild/rules_docker
  name: rules_docker
- type: SDK
  url: https://github.com/bazelbuild/rules_oci
  name: rules_oci
- type: SDK
  url: https://github.com/bazelbuild/rules_proto
  name: rules_proto
- type: SDK
  url: https://github.com/bazelbuild/rules_pkg
  name: rules_pkg
- type: SDK
  url: https://github.com/bazelbuild/bazel-skylib
  name: bazel-skylib (common Starlark functions)
- type: Plugins
  url: https://github.com/bazelbuild/intellij
  name: IntelliJ / CLion / Android Studio plugin
- type: Plugins
  url: https://github.com/bazelbuild/vscode-bazel
  name: VS Code Bazel extension
- type: CodeExamples
  url: https://github.com/bazelbuild/examples
  name: Bazel examples repository
- type: Vocabulary
  url: vocabulary/bazel-build-vocabulary.yml
- type: JSONLD
  url: json-ld/bazel-build-context.jsonld
- type: SpectralRules
  url: rules/bazel-build-rules.yml
- type: License
  url: https://github.com/bazelbuild/bazel/blob/master/LICENSE
  name: Apache License 2.0
- type: Features
  data:
  - name: Multi-Language Support
    description: One build tool spans Java, C++, Go, Python, Rust, Swift, Kotlin, Scala, Android, iOS, Objective-C,
      and dozens of community-maintained language rules.
  - name: Hermetic, Reproducible Builds
    description: Sandboxed action execution and explicit dependency declarations make Bazel builds reproducible across
      machines and CI runners.
  - name: Incremental Builds
    description: Fine-grained action graph and Merkle-tree based caching mean only what changed gets rebuilt, even in
      monorepos with millions of targets.
  - name: Remote Caching and Execution
    description: Bazel speaks the open Remote Execution API (REAPI) so teams can share a Content-Addressable Store and
      offload actions to a remote build farm.
  - name: Bzlmod External Dependencies
    description: MODULE.bazel + the Bazel Central Registry replace the legacy WORKSPACE system with versioned,
      transitive, registry-resolved modules.
  - name: Starlark Extension Language
    description: A deterministic Python-like DSL for writing custom rules, repository rules, module extensions, and
      aspects without touching Bazel internals.
  - name: Build Event Protocol
    description: Every invocation emits a structured BEP/BES stream consumable by CI dashboards, observability tools,
      and flake detectors.
  - name: Query Languages
    description: bazel query, cquery (configured), and aquery (action graph) let you inspect dependency graphs,
      configuration transitions, and the actual actions Bazel will run.
  - name: Toolchain Resolution
    description: Platform-aware toolchain selection lets one BUILD graph target Linux, macOS, Windows, Android, iOS,
      and embedded targets from the same source tree.
  - name: Persistent Workers
    description: Long-lived worker processes (javac, scalac, etc.) amortize JVM and compiler startup across many
      actions for faster incremental builds.
  - name: Bazel Central Registry
    description: Default public index of Bazel modules at bcr.bazel.build with searchable UI at registry.bazel.build.
  - name: Bazelisk Version Launcher
    description: Pins the exact Bazel version per project via .bazelversion so every contributor and CI runner uses
      the same build tool.
  sources:
  - https://bazel.build/
  - https://github.com/bazelbuild/bazel
  - https://github.com/bazelbuild/bazel-central-registry
  - https://bazel.build/external/registry
  - https://bazel.build/external/module
  - https://bazel.build/remote/bep
  - https://github.com/bazelbuild/remote-apis
  updated: '2026-05-25'
maintainers:
- FN: Kin Lane
  email: [email protected]
  X: apievangelist
  url: https://apievangelist.com