# Java Quarkus Development > Java Quarkus development guidelines for building cloud-native applications with fast startup, minimal memory footprint, and GraalVM native builds Use when this capability is needed. - Skill: `tomevault-io/java-quarkus-development` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/java-quarkus-development` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/java-quarkus-development/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: DevOps & Infra - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/java-quarkus-development --- # Java Quarkus Development Best Practices ## Core Principles - Write clean, efficient, and well-documented Java code using Quarkus best practices - Focus on fast startup and minimal memory footprint via GraalVM native builds - Leverage Quarkus extensions for common functionality - Design for containerized and serverless deployments - Follow SOLID principles and microservices architecture patterns ## Development Workflow ### Quarkus Dev Mode - Use `quarkus dev` for rapid iteration with live reload - Leverage continuous testing during development - Use Dev UI for debugging and configuration inspection - Take advantage of Dev Services for local development ## Configuration ### Type-Safe Configuration - Use `@ConfigProperty` for type-safe configuration injection - Group related configs with `@ConfigMapping` interfaces - Validate configuration at startup - Document configuration properties ### Profile-Based Configuration - Use `%dev`, `%test`, `%prod` prefixes for environment-specific configs - Override configs via environment variables in production - Keep sensitive values out of source control - Use `.env` files for local development ## Dependency Injection ### CDI Annotations - Use `@Inject` for dependency injection - Use `@Named` to qualify implementations - Use `@Singleton`, `@ApplicationScoped`, `@RequestScoped` appropriately - Prefer constructor injection for required dependencies ### Bean Discovery - Understand Quarkus build-time bean discovery - Use `@IfBuildProfile` for conditional beans - Avoid reflection-heavy patterns for native builds ## REST API Development ### RESTEasy Reactive - Use `@Path`, `@GET`, `@POST`, etc. for endpoint definitions - Return proper HTTP status codes - Use `@Valid` for input validation - Implement exception mappers for consistent error responses ### Reactive Patterns - Use Mutiny for reactive programming - Leverage `Uni` and `Multi` for async operations - Combine reactive with imperative code where appropriate ## Data Access ### Hibernate ORM with Panache - Use Panache for simplified JPA patterns - Leverage Active Record or Repository patterns - Use `PanacheEntity` for entities with built-in operations - Implement custom queries with `find` and `list` methods ### Database Operations - Use Flyway or Liquibase for migrations - Configure connection pooling with Agroal - Use reactive database clients for non-blocking I/O ## Testing ### JUnit 5 Integration - Use `@QuarkusTest` for integration tests - Use `@QuarkusIntegrationTest` for native image tests - Leverage test profiles for different configurations ### REST Endpoint Testing - Use rest-assured for endpoint testing - Test both success and error scenarios - Verify response bodies and status codes - Test authentication and authorization ## Performance Optimization ### Native Image Optimization - Build native images with GraalVM for production - Test native builds regularly during development - Use `@RegisterForReflection` when needed - Minimize reflection usage ### Memory and Startup - Monitor memory usage in containers - Optimize for serverless cold starts - Use lazy initialization where appropriate ## Observability ### Health Checks - Use MicroProfile Health for liveness and readiness probes - Implement custom health checks for dependencies - Configure Kubernetes probes based on health endpoints ### Metrics - Use MicroProfile Metrics for application metrics - Export metrics in Prometheus format - Add custom metrics for business operations ### Distributed Tracing - Use OpenTracing/OpenTelemetry integration - Propagate trace context across services - Configure sampling appropriately for production ## Security - Use Quarkus Security extensions - Implement authentication with OIDC or JWT - Configure CORS for web clients - Validate and sanitize all inputs - Use HTTPS in production ## Containerization - Use Quarkus container image extensions - Build multi-stage Dockerfiles for native images - Configure resource limits appropriately - Use distroless or minimal base images --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/mindrally) — claim your Tome and manage your conversions.