Quarkus | Supersonic Subatomic Java

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In this Digital-first era, technologies are evolving faster. It helps technologists to develop and deploy faster, more performance-oriented, efficient, and lower memory consumption applications.Quarkus is one such initiative from RedHat. It is designed and developed by RedHat, keeping cloud-native, serverless, and containerized applications future in mind.

As per RedHat definition: “Quarkus is a full-stack, Kubernetes-native Java framework made for Java virtual machines (JVMs) and native compilation, optimizing Java specifically for containers and enabling it to become an effective platform for serverless, cloud, and Kubernetes environments.

Why Quarkus

In today’s digital ecosystem, the use of cloud adoption has been increasing daily. The demand for building serverless and containerized applications has also grown exponentially. The existing Java Frameworks like Spring Boot were not designed keeping serverless and containerization in mind. Hence Java developers are facing challenges building these applications for the latest cloud models.

Quarkus framework is built keeping Kubernetes-native and serverless in mind with the full-stack support of existing Java Libraries and Frameworks.

How does Quarkus work?

Quarkus optimizes Java specifically for Kubernetes by reducing the size of both the Java application and the container image. It eliminates the unwanted or unnecessary java classes/jars during compile time. Other frameworks usually do not remove many of these unwanted Java classes/jars while building the runtime image. Quarkus works with pre-compile modern VMs like GraalVM and HotSpot. Developers can choose to run Quarkus applications over GraalVM or JVM both.

Quarkus uses the GraalVM virtual machine to compile Java applications in an ahead-of-time compilation approach and generates an efficient Kubernetes-native executable file. This file contains the application code, only the required Java libraries, and the minimally required java classes of the runtime JVM. Thus, it helps in minimizing the runtime Java portion as much as possible. 


Image Source : RedHat

Following are the key reasons: how Quarkus generates efficient Java application:

1. Support for GraalVM

    • GraalVM provides high-performance runtime for Java applications. It uses ahead of time compilation techniques to improve the performance and throughput of the applications. Due to the support of GraalVM, an application compiled by Quarkus to a native image uses only the required libraries. Hence, it starts much faster and can run with a much smaller heap than a standard JVM.

2. Native Pre-Booted Container Image

    • Quarkus pre-boots the native images as much as possible and reduces the burden of an image on the runtime environment. The image created by Quarkus already runs most of the startup code before creating the executable. It results in a faster startup of the image. Which in turn supports faster scaling of the Java Applications.

3. Very less or No Reflection Usage

    • Quarkus tries to avoid using heavy processing like Reflection as much as possible. It drastically improves startup time and memory usage. 

4. Reduced Build Time Metadata Processing

    • In a traditional model or other JVM applications, all the classes required to perform the initial application deployment stay around throughout the life of an application. Even though they are used only once in the entire application life cycle. With Quarkus, these unwanted classes do not even load into the production JVM. It results in very low memory utilization, and also faster startup time because all the metadata processing is already done by Quarkus. 

Memory Consumption by Quarkus

In a typical scenario, QuarkUs consume 4 to 10 times lesser memory and are much faster than other Java/Spring Boot applications. The below snapshot shows the memory consumed by the Java Application built with Quarkus vs Traditional Java Stack Frameworks like SpringBoot. It also highlights the memory consumption of QuarkUs with GraalVM and without GraalVM.

Quarkus Memory

Image Source : RedHat

Quarkus is now part of Red Hat Runtimes also. RedHat offers a middleware that comprises products, tools, and components for developing and maintaining cloud-native applications through the use of lightweight runtimes and frameworks for highly distributed cloud architectures, including microservices.

Benefits for Quarkus

Substantial improvement in Java developer productivity (aka Developer Joy): 

    • Quarkus works with almost all popular Java standards, frameworks, and libraries. It also eliminates the need to learn new APIs or switch to any other programming language or IDE altogether. 

    • Quarkus provides several new features like LIVE coding and unified configuration for faster iteration during development. In LIVE coding, changes are automatically and immediately reflected in the running app. Many developers have rated LIVE Coding as one of the key requirements for quick development and testing of applications.

Improvement in operational efficiency and cost : 

    • Quarkus is tailored for containerized, Kubernetes-native development stack, enabling organizations to build and deliver faster. This helps organizations to be more efficient in achieving their business goals and maintain a competitive edge in the market.

    • One of the biggest advantages of Quarkus is low memory consumption and a fast startup time. This directly results in better resource utilization and shorter response time. Better utilization of resources further results in a good amount of cost-saving. Shorter response time further results in a better end-user experience. 

Improvement in Resilience : 

    • Most of the Quarkus applications are containerized, elastic, scalable, and able to meet changing demand, resulting in a more reliable and resilient system. Quarkus containerized images load extremely fast. This helps not only in scaling the business applications on short notice but also very useful in switching to other images during failover situations. 


Quarkus has a promising future as it directly helps the Technologist to address the current and future demands of scalability and faster booting of containers within Kubernetes. It also helps developers to take advantage of Live Coding features. Hence developers can build applications faster and become more efficient using Quarkus.



Written by 

Ravinder is a seasoned and passionate IT professional with over two decades of progressive experience in architecting, developing, implementing & leading Enterprise IT solutions in Hi-Tech, Insurance, Manufacturing, Telecommunication & Education industries. Strong Technical & Management Background in leading and motivating project, program and COE teams. He has superior expertise in digital transformation, product engineering, building SAAS platforms, developing methodologies, developer supervision and client relations.