Quarkus vs WildFly Application Server

This article provides a comparison of the features of two popular Java Enterprise Runtimes: WildFly Application Server and Quarkus framework. While both offer robust support for Java applications, their distinct approaches to development, deployment, and scalability cater to diverse use cases.

Comparing Quarkus and WildFly. Fair comparison ?

Firslty a disclaimer note: Comparing WildFly, a full-fledged Jakarta EE application server, with Quarkus, a lightweight, modern runtime framework, might seem like an apple-to-pear comparison. WildFly encompasses a comprehensive set of services and functionalities required for traditional enterprise-level applications, whereas Quarkus focuses on lightweight, cloud-native, and microservices-oriented development.

Therefore, the purpose of this article cannot be to determine which one is better. Rather, we want to explore their distinct use cases and design philosophies so that you can make an informed decision.

Let’s break down this article in four distinct areas.

Part one: Runtime environment

Runtime environmentQuarkus is a Runtime Environment and a TCK to build, test and debug Java and Native Applications.WildFly is a Modular full-fledged Java Application Server that provides the API to host Jakarta EE 10 Applications ( and Java EE API in earlier versions).
DeploymentQuarkus philosopy is to act as a Microservice. Therefore, each Quarkus Runtime will execute a single application.Each application is a module. [1].Therefore, you can deploy multiple application on it. An Application Context will be created with each application. Application can communicate with each other using different strategies.
ExecutionYou can run Quarkus application in JVM Mode or generate a native application for your environment.WildFly runs Java applications.
Re-DeploymentQuarkus provides automatic live-reload of applications when running in Development mode.You need to re-deploy applications when you apply changes to them for changes to take effect.
[1] Please note that you can also opt for running WildFly applications as Bootable JAR Applications. Read this article for more information: Turn your WildFly application in a Bootable JAR

Round two: Configuration

ConfigurationQuarkus relies on a set of Config Sources based on the MicroProfile Config specification which you deploy with your applications.WildFly uses an XML Configuration file which is part of the application server infrastructure.
InterfacesQuarkus ships with a Dev UI to view/edit the Configuration and to manage Continuous Testing and active Extensions.WildFly has an advanced set of Management Interfaces (Web Console and CLI) to manage single or clustered instances of WildFly both on-line and offline
ModelQuarkus is a standalone execution environment.WildFly is both a standalone and domain runtime environment. You can use domain mode to create logical separation between Server Groups.

Round three: Memory and Speed

Startup timeQuarkus typically has an extremely fast start-up time as it uses several optimizations such as ahead-of-time (AOT) compilation to generate native executables. WildFly has a start-up time comparable to other Application Servers. It is however simple to create leaner distributions with the Galleon Tool..
Resource consumptionQuarkus typically has lower memory footprint (both in JVM mode and native mode) as it is optimized for running on containers. This makes it a perfect fit for a Microservice environmentWildFly will typically require more memory and CPU resources to run the Modules which are part of the application server infrastructure.
ScalabilityQuarkus is designed to be scalable, so it can handle large numbers of concurrent users. This is because Quarkus applications are typically deployed as microservices, which are small, independent units of code that can be scaled independently of each other.WildFly is also designed to be scalable, but it uses a more traditional application server, which is designed to run large, monolithic applications. It provides out of the box support for Horizontal clustering

Round four: Application Development

Application InitializerQuarkus has a rich TCK to bootstrap applications that are available both online and offline. You can also use these tools to cherry-pick the extensions you need for your applications.You can use Maven archetypes to bootstrap applications and WildFly Maven plugin [2] to simplify application deployment
ExtensionsQuarkus has a large set of ecosystem of extensions which spans beyond the Jakarta EE specification including Cloud, Messaging and Event-Driven systems, No-SQL DB and more.WildFly provides support for Jakarta EE and MicroProfile compatible applications.
IntegrationQuarkus integration focuses on Event Driven systems and Camel extensions. Partially supports legacy integrations (SOAP Web Services and EIS integration with a Resource Adapter). WildFly has mature support both for REST-based services and legacy integration systems (SOAP Web Services and EIS integration with Resource Adapter).
CloudQuarkus has native support for building Container Images of your applications. Also, its extensions enable automatic deployment of the applications on Kubernetes.To deploy WildFly applications on the Cloud you can use WildFly official Container images and configure your Projects or Helm Charts to deploy the applications on Kubernetes.

[2] WildFly Maven plugin is discussed in greater detail in this article: How to configure and run Maven WildFly plugin


In conclusion, the comparison between Quarkus and WildFly reveals two robust Java Enterprise Runtimes, each with its distinct strengths and suitability for various use cases.

Quarkus, known for its lightweight, microservices-oriented architecture, proves advantageous in scenarios demanding rapid startup times, low memory consumption, and efficient utilization in cloud-native environments. Its ability to build highly optimized, GraalVM-native applications caters well to modern, resource-constrained, and scalable projects.

Conversely, WildFly, being a full-fledged application server, thrives in enterprise-scale applications requiring comprehensive Java EE and Jakarta EE support, extensive middleware functionalities, and a wide array of enterprise-grade services. Its established ecosystem and robustness make it an ideal choice for traditional, larger-scale applications that demand a comprehensive Java EE environment.

wildfly vs quarkus