rules_quarkus — Bazel Rules for Quarkus Applications

Bazel rules for building Quarkus applications with build-time augmentation support.

Overview

rules_quarkus provides native Bazel support for building Quarkus applications, filling the gap where no official Bazel rules exist for the Quarkus framework. The project implements Quarkus's unique build-time augmentation process within Bazel's build system, enabling developers to use Bazel's powerful dependency management and caching while maintaining full Quarkus functionality.

Quick Start

Installation

Add the following to your MODULE.bazel:

bazel_dep(name = "rules_quarkus", version = "0.1.0")

# Add Quarkus dependencies
maven = use_extension("@rules_jvm_external//:extensions.bzl", "maven")
maven.install(
    name = "maven",
    artifacts = [
        "io.quarkus:quarkus-arc:3.20.1",
        "io.quarkus:quarkus-rest:3.20.1",
        "io.quarkus:quarkus-vertx-http:3.20.1",
        "jakarta.ws.rs:jakarta.ws.rs-api:4.0.0",
        # ... add more dependencies as needed
    ],
)

Basic Usage

Create a BUILD.bazel file:

load("//quarkus:quarkus.bzl", "quarkus_application")

quarkus_application(
    name = "my-app",
    srcs = glob(["src/main/java/**/*.java"]),
    resources = glob(["src/main/resources/**/*"]),

    # Regular dependencies (APIs)
    deps = [
        "@maven//:jakarta_ws_rs_jakarta_ws_rs_api",
        "@maven//:jakarta_enterprise_jakarta_enterprise_cdi_api",
    ],

    # Quarkus runtime extensions
    runtime_extensions = [
        "@maven//:io_quarkus_quarkus_arc",
        "@maven//:io_quarkus_quarkus_rest",
        "@maven//:io_quarkus_quarkus_vertx_http",
    ],

    # Quarkus deployment modules (for build-time processing)
    deployment_extensions = [
        "@maven//:io_quarkus_quarkus_arc_deployment",
        "@maven//:io_quarkus_quarkus_rest_deployment",
        "@maven//:io_quarkus_quarkus_vertx_http_deployment",
    ],

    # Main class (required)
    main_class = "io.quarkus.runner.GeneratedMain",
)

Build and run:

# Build the application
bazel build //:my-app

# Run the application
./bazel-bin/my-app/my-app

# Access your endpoints
curl http://localhost:8080/hello

Supported Extensions

rules_quarkus supports a wide range of Quarkus extensions organized in 5 tiers:

Tier 1: Core (Essential)

Extension	Description
quarkus-arc	CDI dependency injection
quarkus-rest	RESTful web services
quarkus-rest-jackson	JSON serialization
quarkus-vertx-http	HTTP server
quarkus-mutiny	Reactive programming

Tier 2: Database (Reactive)

Extension	Description
quarkus-reactive-oracle-client	Reactive Oracle database client
quarkus-reactive-mysql-client	Reactive MySQL database client
quarkus-redis-client	Redis client

Tier 3: Messaging

Extension	Description
quarkus-messaging-kafka	Apache Kafka messaging
quarkus-messaging-rabbitmq	RabbitMQ messaging
quarkus-grpc	gRPC services

Tier 4: Observability

Extension	Description
quarkus-micrometer-registry-prometheus	Prometheus metrics
quarkus-smallrye-health	Health checks

Tier 5: Quarkiverse

Extension	Description	Version
quarkus-unleash	Feature flags	1.10.0
quarkus-langchain4j-*	AI/LLM integration	0.26.1
quarkus-tika	Content analysis	2.1.0

Architecture

rules_quarkus implements Quarkus's three-layer build architecture in Bazel:

┌─────────────────┐    ┌─────────────────┐    ┌─────────────────┐
│   Layer 1:      │    │   Layer 2:      │    │   Layer 3:      │
│   Compile       │───▶│   Augment       │───▶│   Runtime       │
│                 │    │                 │    │                 │
│ java_library    │    │ QuarkusBootstrap│    │ Executable      │
│ Standard        │    │ Build-time      │    │ Application     │
│ compilation     │    │ processing      │    │ with CDI, etc.  │
└─────────────────┘    └─────────────────┘    └─────────────────┘

Layer 1: Compile

Standard Java compilation using Bazel's java_library. Source files are compiled to bytecode with minimal processing.

Layer 2: Augment

Quarkus build-time augmentation using the official QuarkusBootstrap API:

• Jandex bytecode indexing
• CDI proxy generation
• Configuration processing
• Extension discovery
• Optimized bytecode generation

Layer 3: Runtime

Executable application with fully processed Quarkus features:

• Fast startup time
• Low memory usage
• Build-time optimizations applied

Requirements

Component	Version
Bazel	7.x+
Java	21
Quarkus	3.20.1

Examples

We provide several example applications to help you get started with rules_quarkus:

🚀 Hello World

A minimal "Supersonic Subatomic" REST API showing the basic setup.

• Location: examples/hello-world/
• Build: bazel build //examples/hello-world:hello-world
• Run: ./bazel-bin/examples/hello-world/hello-world

🏗️ Demo Extensions Showcase

A comprehensive example demonstrating multi-tier extensions (REST, Jackson, Mutiny, Health, and Metrics).

• Location: examples/demo-extensions/
• Build: bazel build //examples/demo-extensions:demo-extensions
• Run: ./bazel-bin/examples/demo-extensions/demo-extensions

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Macros and Rules

quarkus_application

Main macro for building Quarkus applications.

Parameters:

• name: Application name (Required)
• srcs: Java source files
• resources: Application resources (application.properties, etc.)
• deps: Regular dependencies (non-Quarkus libraries)
• runtime_extensions: Quarkus runtime extension modules
• deployment_extensions: Quarkus deployment modules
• main_class: Required. Set to your @QuarkusMain class or the main class from pom.xml. Use "io.quarkus.runner.GeneratedMain" for standard applications.
• jvm_flags: JVM flags for running the application

quarkus_library

Creates a library that can be used as a dependency for Quarkus applications.

Parameters:

• name: Library name
• srcs: Java source files
• resources: Resources
• deps: Dependencies
• extensions: Quarkus extensions used by this library

Resources

• Architecting Deterministic Quarkus Builds: Native Support for Bazel — An in-depth look at the architecture and motivation behind rules_quarkus.
• Deep Dive: Taming the Quarkus ClassLoader for Hermetic Bazel Builds — The technical journey of solving ClassLoader challenges and Quarkus Issue #52915.

Contributing

We welcome contributions! Please see CONTRIBUTING.md for guidelines on:

• Setting up the development environment
• Building and testing changes
• Submitting pull requests
• Reporting issues

License

Licensed under the Apache License, Version 2.0.

Authors

Created and maintained by:

• @kinhluan
• @tructxn
• @Nhannguyenus24

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Note: This project is a community-driven effort and is not officially affiliated with Red Hat or the Quarkus project.

This project is an evolution of the work originally started at tructxn/rule-quarkus.