Top Glassfish Alternatives for Modern Java EE Development
GlassFish v3, a commendable open-source implementation of the Java EE 6 platform, offered flexibility, extensibility, and developer-friendly features. It enabled organizations to leverage new Java EE capabilities and streamline their development and deployment cycles. However, as technology evolves, many developers and businesses seek more modern, robust, or specialized alternatives to Glassfish. Whether you're looking for enhanced cloud-native support, specific performance optimizations, or a different community focus, there are several compelling Glassfish alternative options available today.
Top Glassfish Alternatives
Finding the right application server can significantly impact your project's success. Here are some of the best Glassfish alternatives that cater to various needs, from cloud-native deployments to specific language support.

Payara Server
Payara Server is an excellent Glassfish alternative, recognized as an open-source, cloud-native middleware platform. It's built for reliable and secure deployments of Java EE (Jakarta EE) applications and is available across Mac, Windows, and Linux. Key features include robust Backend support, Clustering capabilities, MicroProfile compatibility, and a powerful REST API, making it ideal for modern, distributed architectures.

JBoss
JBoss, Red Hat's Java EE compliant application server, stands out as a powerful Glassfish alternative. It's dual-licensed as open source, making it accessible on Mac, Windows, and Linux. JBoss is widely used for web development and offers a mature, enterprise-grade environment for deploying Java applications.

appserver.io
For PHP developers seeking a powerful application server, appserver.io is a unique Glassfish alternative. It's a multithreaded application server for PHP written entirely in PHP, offering real multi-threading capabilities. This open-source solution, available for Mac, Windows, Linux, and self-hosted environments, provides useful services for developers, including robust Web Development support and a built-in Web Server.

WebSphere Application Server
IBM's WebSphere Application Server is a strong commercial Glassfish alternative, providing the availability and security critical for business operations while optimizing costs. Available on Windows and Linux, it's designed to build, deploy, and manage robust, agile Java applications, making it a reliable choice for enterprise-level web development.

JOnAS
JOnAS, an OSGi Enterprise Server by OW2, is a leading edge Java EE 5 certified open-source Glassfish alternative. Licensed under LGPL, it's supported by a vibrant development community and is compatible with Mac, Windows, and Linux. JOnAS is a solid choice for web development, offering a flexible and community-driven platform.

Mako Server
The Mako Server offers a distinctive Glassfish alternative for those working with Lua. It's an application server with an API similar to the Java Servlet API, but designed for server-side web applications in Lua. Available for free personal use on Mac, Windows, and Linux, its portability makes it an appealing option for specific web development needs.

Apache Geronimo
Apache Geronimo is a robust Java EE 5-certified application server for web and enterprise applications. As a free and open-source Glassfish alternative, it aligns with Sun's Java EE platform specification and runs on Mac, Windows, and Linux. Geronimo is a strong contender for those requiring a reliable and community-backed server for general web development.
Each of these Glassfish alternative options presents unique strengths and features. We encourage you to explore them further to determine the best fit for your specific project requirements, development stack, and deployment environment.