vertx-expert

Keyword: vertx | Platforms: gemini,claude,codex

Reactive Foundation Expert Skill - Specialized in the Eclipse Vert.x event-driven ecosystem.

Core Mandates

• Don't Block the Event Loop: Never perform blocking operations (I/O, heavy computation) in an Event Loop thread. Use executeBlocking() if needed.
• Polyglot Design: Verticles communicate via Event Bus, making components decoupled and language-agnostic.
• Async First: Mandate Future, Promise, and Handler patterns for non-blocking execution flow.
• Concurrency: Understand Verticle instances and single-threaded concurrency model.

Reactive Vert.x Components

• Vert.x Web: Building high-performance, non-blocking HTTP APIs.
• Event Bus: Distributed messaging system for horizontal scaling.
• Reactive Clients: Using MySQL, PostgreSQL, Redis, and Kafka clients without blocking threads.
• Context API: Managing and propagating thread-local storage in an asynchronous environment.

Vert.x + Quarkus Integration

• Reactive Engine: Understanding how Quarkus uses Vert.x as its underlying I/O engine.
• Custom Verticles in Quarkus: Registering and deploying Verticles within the Quarkus lifecycle.
• Vert.x Mutiny: Leveraging SmallRye Mutiny (Uni, Multi) over standard Vert.x Futures.

Advanced Patterns

• Circuit Breaker: Handling service failures gracefully in a distributed system.
• Service Discovery: Finding and consuming services in a reactive manner.
• Clustering: Using Hazelcast or Infinispan to cluster the Event Bus.

Expert Tips

• Monitor the Event Loop using BlockedThreadChecker log warnings.
• Prefer Vert.x Web Client over legacy RestTemplate or blocking clients.
• Use Vertx.currentContext() for low-level async state management.

🌐 Reactive Knowledge Sources

Directive: If you encounter blocked thread warnings or need to implement complex event-driven flows, use web_fetch on these official guides.

• Don't Block!: Blocking Code in Vert.x Guide - Essential reading for performance.
• Event Bus Patterns: Vert.x Distributed Event Bus - Messaging and scaling.
• Reactive SQL: Vert.x Reactive SQL Clients - Non-blocking database access.
• Vert.x + Mutiny: SmallRye Mutiny for Vert.x - Reactive patterns for Quarkus.

References

• Eclipse Vert.x Official Website
• Vert.x Web Documentation
• SmallRye Mutiny Documentation

Skill Interoperability

The vertx-expert 🌀 skill serves as the reactive engine for:

• quarkus-expert ⚡: Quarkus is built on top of Vert.x for non-blocking I/O and high performance. It depends on java-expert ☕ for language-level reactive features.