Spring Boot helps you to create Spring-powered, production-grade applications and services with absolute minimum fuss.

Free and Open Source, Distributed, RESTful Search Engine

Getting Started with Spring Boot 3:

Hystrix is a latency and fault tolerance library designed to isolate points of access to remote systems, services and 3rd party libraries, stop cascading failure and enable resilience in complex di…

Zipkin is a distributed tracing system

Vert.x is a tool-kit for building reactive applications on the JVM

Very spicy additions to the Java programming language.

Admin UI for administration of spring boot applications

LangChain4j is an idiomatic, open-source Java library for building LLM-powered applications on the JVM. It offers a unified API over popular LLM providers and vector stores, and makes implementing …

Apereo CAS - Identity & Single Sign On for all earthlings and beyond.

Java JWT: JSON Web Token for Java and Android

A simple expressive web framework for java. Spark has a kotlin DSL https://github.com/perwendel/spark-kotlin

A damn simple library for building production-ready RESTful web services.

📈 Capturing JVM- and application-level metrics. So you know what's going on.

Distributed Graph Database

Apache Ignite

A scalable, distributed Time Series Database.

RStudio is an integrated development environment (IDE) for R

MockServer enables easy mocking of any system you integrate with via HTTP or HTTPS with clients written in Java, JavaScript and Ruby. MockServer also includes a proxy that introspects all proxied t…

An application observability facade for the most popular observability tools. Think SLF4J, but for observability.

"Maven-node-grunt-gulp-npm-node-plugin to end all maven-node-grunt-gulp-npm-plugins." A Maven plugin that downloads/installs Node and NPM locally, runs NPM install, Grunt, Gulp and/or Karma.

Official GeoServer repository

Real-time transport layer for Java AI agents. Build once with @Agent — deliver over WebSocket, SSE, gRPC, and WebTransport/HTTP3. Talk MCP, A2A and AG-UI.

Vert.x examples

Java agent that enables class reloading in a running JVM

Unirest in Java: Simplified, lightweight HTTP client library.

An in-memory file system for Java

Security engine for Java (authentication, authorization, multi frameworks): OpenID Connect, SAML2, CAS, OAuth, LDAP, JWT...

Docker container orchestration platform

Dozer is a Java Bean to Java Bean mapper that recursively copies data from one object to another.