Best Free Application Server Software of 2025

A powerful iPaaS platform for integration and business process automation. Linx is a powerful integration platform (iPaaS) that enables organizations to connect all their data sources, systems, and applications. The platform is known for its programming-like flexibility and the resulting ability to handle complex integrations at scale. It is a popular choice for growing businesses looking to embrace a unified integration strategy.

RasPiEsi, the world's smallest open source ERP application server powered by Epesi, runs on Raspberry Pi Zero running with only 1 core and 512MB of RAM. Part of Epesi ENS – the first FOSS Enterprise Neuronal System. Epesi BIM stack on LLMP: - Linux Lighttpd - MariaDB - tuned PHP 7.4 FPM + memcached ZRAM On November 4, 2023, neofetch added and updated 77 package for version 1.1 (Joziu). RasPiEsi was the smallest Epesi Node I could build, with RAM usage at only 133MB. This tiny server runs Epesi very well, especially on a quick SD card. It should run on any Raspberry Pi – from the $5 RPi zero with no WiFi, 1 CPU and 512 MB RAM (used to create the disk image) to the high-end RPi 4 – without modification. The RPi 3 worked fine - no modifications, just swapped units! MIT License (c) Copyright 2024 by Janusz and Karina Tilek

We assist companies from all industries to accelerate their software development processes. The feature flag solution is clearly laid out so you can switch on and off your features at any time. It can be used for User Targeting, Canary Releases and Experimenting.

Appwrite offers a cloud backend solution, simplifying the construction of your backend infrastructure with minimal coding across preferred languages and frameworks. This platform empowers developers to concentrate on creativity and design, minimizing the grind of backend development chores. Products Appwrite provides you with: - Authentication: 30+ login methods, support for teams, roles, and user labels - Databases: Never paused, fast in-memory caching, advanced permission models, relationships support - Storage: File encryption at rest and transit, built-in image transformation capabilities, advanced compression with WebP/Brotli support - Functions: Automatic deployment from GitHub - Messaging: SMS, email, and push notification support - Real-time: Unlimited subscriptions By utilizing Appwrites’ features, you save time and ensure your products are stable and secure for your end users. With Appwrite, you always own your data, so you never have to fear vendor lock-in.

Developers have historically faced a dilemma with cloud infrastructure, having to choose between costly yet rigid platforms that struggle to scale and intricate large cloud solutions that require significant learning and extensive operations teams. Render provides an ideal solution by combining user-friendliness with robust power and scalability, capable of supporting anything from a basic HTML page to sophisticated applications consisting of numerous microservices. This balance allows developers to focus more on innovation rather than navigating cumbersome systems.

Our cutting-edge in-memory technology, alongside our application server, allows you to create exceptionally fast enterprise software without the need for custom tools or unfamiliar syntax. Starcounter applications can deliver performance improvements ranging from 50 to 1000 times while maintaining simplicity and ease of use. You can develop these applications using standard C#, LINQ, and SQL, with ACID transactions also implemented in familiar C# code. The platform provides full support for Visual Studio, including features like IntelliSense, a debugger, and a performance profiler—everything you love about development, but without unnecessary complications. By employing standard C# syntax and the MVVM pattern, you can harness our ACID in-memory technology alongside a lightweight client UI to achieve remarkable performance. Starcounter's technology starts delivering business value right from the outset, utilizing proven solutions that are already handling millions of transactions for high-demand clients. This integration of the ACID in-memory database and an application server into a single platform offers unmatched performance, simplicity, and affordability. Ultimately, Starcounter empowers developers to build robust applications that not only meet but exceed modern business demands.

NGINX Open Source is the web server that supports over 400 million websites globally. Built upon this foundation, NGINX Plus serves as a comprehensive software load balancer, web server, and content caching solution. By opting for NGINX Plus instead of traditional hardware load balancers, organizations can unlock innovative possibilities without being limited by their infrastructure, achieving cost savings of over 80% while maintaining high performance and functionality. It can be deployed in a variety of environments, including public and private clouds, bare metal, virtual machines, and container setups. Additionally, the integrated NGINX Plus API simplifies the execution of routine tasks, enhancing operational efficiency. For today's NetOps and DevOps teams, there is a pressing need for a self-service, API-driven platform that seamlessly integrates with CI/CD workflows, facilitating faster app deployments regardless of whether the application utilizes a hybrid or microservices architecture, which ultimately streamlines the management of the application lifecycle. In a rapidly evolving technological landscape, NGINX Plus stands out as a vital tool for maximizing agility and optimizing resource utilization.

Internet Information Services (IIS) on Windows® Server serves as a versatile, secure, and easily manageable web server suitable for a wide array of online hosting needs. Whether it's media streaming or complex web applications, IIS boasts a scalable and open framework designed to meet even the highest demands with efficiency. Its robust features allow for seamless integration and performance across various internet-based services.

You focus on coding while we take care of everything else. Instantly deploy serverless applications around the world to ensure outstanding performance, dependability, and scalability. Say goodbye to the hassle of configuring auto-scaling, managing load balancers, or incurring costs for unused capacity. Your traffic will be automatically distributed and balanced across thousands of servers, allowing you to rest easy while your code adapts seamlessly. Each deployment connects to a network of data centers utilizing V8 isolates, ensuring rapid execution. Your applications benefit from Cloudflare's vast network, which is mere milliseconds away from nearly every internet user. Kick off your project with a template in your preferred programming language to begin developing an app, function, or API quickly. We provide a variety of templates, tutorials, and a command-line interface to get you started efficiently. Unlike many serverless platforms that face cold starts during deployments or spikes in service demand, our Workers execute your code immediately, eliminating delays. You can enjoy the first 100,000 requests each day at no cost, with affordable plans beginning at just $5 for every 10 million requests. With our service, you can focus on your coding goals while we ensure your applications run smoothly and efficiently.

Lucee stands out as the premier open-source CFML application server and engine, offering an extensive array of functionalities, including tags and functions that facilitate various web-related tasks. From handling images and PDF documents to managing XML, strings, numbers, and dates, Lucee is equipped to tackle it all! Additionally, Lucee simplifies the process of both consuming existing web services and creating new ones. As a community-driven open-source project, we invite contributions in multiple forms. For those interested in coding, our Contributors guide is a great place to start. You can also participate by engaging in discussions on our forum or contributing to the Lucee Association Switzerland's source code repository. Other ways to get involved include writing articles for our newsletter or blog, assisting with documentation, or providing support on our forums. Your involvement can help enhance the Lucee ecosystem, making it even more robust and user-friendly for everyone.

Apache TomEE, often referred to as “Tommy,” is an application server that is fully certified for Jakarta EE 9.1 and is built upon Apache Tomcat, originating from a standard Apache Tomcat zip file. The process begins with Apache Tomcat, followed by the addition of necessary libraries, culminating in a packaged version that incorporates EE functionalities, thus creating TomEE. This server is stable and production-ready, with Apache TomEE 8.0 implementing Java EE 8/Jakarta EE 8 and maintaining support for the javax namespace, while operating on Java 8 or later versions. It is primarily compliant with the Jakarta EE 9.1 web profile and supports the new jakarta namespace, functioning seamlessly on Java 11 or newer. Apache TomEE is available in four variations: web profile, MicroProfile, Plus, and Plume. The web profile of Apache TomEE provides essential services such as servlets, JSP, JSF, JTA, JPA, CDI, bean validation, and EJB Lite. The MicroProfile variant enhances the server with additional support for MicroProfile features, while the Plus and Plume editions expand capabilities to include JMS, JAX-WS, and other functionalities. Overall, Apache TomEE is a versatile and robust solution for developers looking to leverage Jakarta EE in their applications.

Apache Geronimo is a collection of open-source projects aimed at delivering JavaEE/JakartaEE libraries along with Microprofile implementations. Our focus is on providing reusable components from Java EE that are not only widely utilized but also actively maintained! The framework offers robust libraries that adhere to the specifications of Java EE and Jakarta EE, while also emphasizing OSGi bundle metadata. The XBean project aspires to develop a plugin-based server similar to Eclipse's plugin architecture for its IDE. This initiative will enable the discovery, downloading, and installation of server plugins from an online repository. Furthermore, our framework supports a variety of IoC systems, includes the ability to operate without an IoC system, facilitates JMX without requiring JMX code, and manages lifecycles and class loaders effectively, alongside seamless Spring integration. Additionally, Apache Geronimo encompasses multiple Microprofile implementations, and the Apache Geronimo Arthur project seeks to establish a lightweight layer over Oracle GraalVM, enhancing its capabilities. In essence, Apache Geronimo is committed to evolving and adapting to the needs of developers in the Java ecosystem.

Supported application servers for production or containerized deployments that are compatible with Jakarta EE & MicroProfile

Caddy streamlines your infrastructure by managing TLS certificate renewals, OCSP stapling, serving static files, reverse proxying, Kubernetes ingress, and more. Its modular design allows for enhanced functionality within a single, static binary that can be compiled for any platform. Caddy operates exceptionally well in container environments due to its lack of dependencies, including libc. You can deploy Caddy almost anywhere. It automatically acquires and renews TLS certificates for your websites and even includes OCSP response stapling. The innovative certificate management capabilities of Caddy are among the most advanced and dependable available. Developed in Go, Caddy provides improved memory safety compared to servers built with C. A robust TLS stack supported by the Go standard library underpins a substantial portion of global Internet traffic. Caddy serves as both an adaptable, efficient static file server and a formidable, scalable reverse proxy, making it a versatile choice for a variety of applications. Additionally, its user-friendly configuration and seamless integration make it an appealing option for developers seeking simplicity and effectiveness.

Apache Tomcat® is an open-source software that serves as a realization of the Jakarta Servlet, Jakarta Server Pages, Jakarta Expression Language, Jakarta WebSocket, Jakarta Annotations, and Jakarta Authentication specifications, which fall under the Jakarta EE umbrella. This versatile software is integral to a vast array of large-scale, essential web applications utilized by various industries and organizations. You can find stories from some of these users on the PoweredBy wiki page. The Apache Tomcat Project is excited to announce the launch of version 10.0.10 of Apache Tomcat, which incorporates specifications from the Jakarta EE 9 platform. This new version aims to enhance performance and provide improved features for developers and organizations alike.