Optimizing Java for the Cloud-Native Era with Quarkus

This article explores how Quarkus can help organizations reduce costs, streamline development, and modernize their Java applications for today’s cloud-native environments. It outlines the real-world benefits of adopting Quarkus and highlights how its core features address the performance and scalability challenges commonly associated with traditional Java frameworks.

Quarkus is already being adopted across industries. One example is Orange, a global telecom provider that selected Quarkus to support its 5G API initiative, and benefited from fast startup times, a lightweight footprint, and seamless integration with Kubernetes.

After evaluating multiple frameworks, Orange chose Quarkus as the optimal solution for exposing 5G APIs, thanks to its fast startup, lightweight footprint, modularity, and seamless Kubernetes deployment. Quarkus successfully deployed 10 APIs across 4G/5G network cores, with smooth upgrades and optimized resource usage. This solidified Quarkus as a key technology for telecom innovation.

For a collection of user stories from the community, see the Quarkus user stories blog series. These stories highlight how different teams and organizations are using Quarkus in the real world.

What does Quarkus have to offer?

Developer joy with live coding and dev mode

Quarkus streamlines the traditional write-compile-deploy-refresh cycle by offering live coding support out of the box. As developers make changes, Quarkus automatically detects, recompiles, and redeploys the application, which eliminates the need for manual restarts.

While similar functionality has existed through third-party tools, Quarkus integrates it natively and without licensing overhead. This significantly boosts productivity and enhances the developer experience.

Cost efficiency and performance

By optimizing for low memory usage and fast startup times, Quarkus enables higher-density deployments and rapid scaling.

For comparable workloads, Quarkus typically consumes fewer resources such as CPU and memory, which can lead to significant cost savings in cloud environments.

However, organizations considering the switch should always measure and evaluate their specific workloads to validate these benefits in practice.

Reactive at its core

At its core, Quarkus is built on Eclipse Vert.x, a high-performance reactive toolkit. Still, it allows developers to work primarily in an imperative style while leveraging the performance benefits of its reactive underpinnings.

This hybrid approach allows developers to squeeze out even more efficiency from traditional imperative programming while offering the flexibility to adopt reactive patterns where they make sense. Unlike traditional reactive-only frameworks, Quarkus enables developers to combine both imperative and reactive styles in a single application.

This is particularly beneficial for systems requiring high throughput and low latency, ensuring that applications remain robust under heavy load.

Quarkus’s reactive model makes it ideal for event-driven architectures and microservices.

A basic example of reactive messaging in Quarkus:

@ApplicationScoped
public class PriceConverter {

    @Incoming("prices")
    @Outgoing("converted-prices")
    public double convert(double priceInEuro) {
        return priceInEuro * 1.1;
    }
}

In this example, prices are received from one channel (prices), converted, and sent to another channel (converted-prices). This pattern supports high-throughput, event-driven processing with clean and efficient logic.

An example of a reactive HTTP endpoint using reactive routes in Quarkus:

@ApplicationScoped
public class GreetingRoute {

    @Route(path = "/hello", methods = HttpMethod.GET)
    public Uni hello() {
        return Uni.createFrom().item("Hello from reactive route!");
    }
}

This route handles HTTP GET requests reactively using Uni from Mutiny, making it easy to build non-blocking, low-latency APIs.

Which of your current development pains could Quarkus solve?

One often-overlooked benefit of Quarkus is how it improves onboarding and standardization across teams.

With built-in conventions, automatic service provisioning, and curated extension defaults, Quarkus helps developers get up to speed quickly and encourages consistent patterns across projects.

Dev Services

Quarkus Dev Services reduce friction during development and testing by automatically provisioning required services such as databases, message brokers, or identity providers.

For example, if your application includes PostgreSQL, Kafka, or Keycloak extensions, Quarkus can spin up the necessary containers without any manual setup. This allows you to focus on coding instead of configuring infrastructure, accelerating your local development workflow.

Vast extension ecosystem

Quarkus offers a rich extension ecosystem that simplifies integration with essential technologies such as databases, messaging systems, authentication providers, and cloud services.

In addition to official extensions, the Quarkiverse community provides a growing collection of open-source extensions maintained by contributors across the ecosystem. This broadens the range of supported technologies and enables developers to benefit from shared solutions and community expertise.

Popular extensions include:

• quarkus-hibernate-orm and quarkus-jdbc-postgresql for seamless data persistence.
• quarkus-smallrye-reactive-messaging and quarkus-kafka-client for reactive messaging and Apache Kafka integration.
• quarkus-oidc for implementing OpenID Connect authentication and securing applications.
• quarkus-micrometer and quarkus-opentelemetry for observability, metrics, and tracing.
• quarkus-container-image-docker and quarkus-kubernetes for containerization and deployment to Kubernetes platforms.

These extensions are widely adopted because they reduce boilerplate, provide reliable default configurations out of the box, and follow cloud-native best practices—making it easy to plug Quarkus into real-world architectures.

“OK, I would like to try it, but is it easy enough to migrate my workflow to Quarkus?”

Migrating to a new framework can feel daunting, even when it promises better performance, lower costs, and an improved developer experience. It’s like being offered a better house in a better neighborhood, but hesitating because of the hassle of packing, moving, and settling in.

With Quarkus, the transition doesn’t have to be disruptive. Thanks to its compatibility with standard Java APIs, support for Jakarta EE and Spring, and a wide range of extensions, many projects can adopt Quarkus incrementally without rewriting existing code. Whether you’re coming from a traditional Java EE application server, a Spring-based stack, or another framework such as Micronaut or Dropwizard, Quarkus provides familiar APIs, tooling, and migration guides to ease the transition.

The platform supports commonly used Jakarta specifications like JAX-RS, CDI, JPA, and Bean Validation out of the box. For Spring users, the compatibility layer includes support for widely used annotations and components. See the Spring DI guide to learn more.

Need assistance getting started? You’re not alone. The Quarkus team offers expert guidance throughout the migration journey, from initial architecture reviews to production readiness. Whether you’re evaluating the framework or planning a full transition, support is available to help ensure a smooth and successful adoption.

All it takes is a decision to move forward. Your team deserves a faster, leaner, and cloud-native future.

Concluding note

Quarkus is redefining Java development by combining modern features with the robustness of the Java ecosystem.

Its focus on developer productivity, performance, and seamless integration positions it as a formidable framework for building efficient, cloud-native applications.

Whether you’re looking to optimize costs, enhance development speed, or adopt a reactive approach, Quarkus is a game-changer for Java developers.

Do you want to know more? Keep reading the second article in the series:

Quarkus: A Runtime and Framework for Cloud-Native Java

• Cloud
• Kubernetes
• Maven
• Microservices
• Observability
• Performance
• reactive
• Security

Michal Maléř

Author

Red Hat Technical Writer | Eclipse Foundation Commiter | Sovryn ex-contributor | Hackernoon Blockchain writer| mickeymaler.com