Open Liberty

Open Liberty
Name	Open Liberty
Developer	IBM, Eclipse Foundation
Released	2017
Programming language	Java
Platform	Java SE, Jakarta EE
License	Eclipse Public License

Open Liberty is a Java application server inspired by microservices and cloud-native architectures, designed to provide a modular, lightweight runtime for Jakarta EE and MicroProfile applications. It is developed in collaboration with IBM and the Eclipse Foundation and is positioned as an extensible, production-ready runtime for enterprises, cloud providers, and open-source projects. The project interfaces with a broad ecosystem including cloud platforms, developer tools, standards bodies, and commercial vendors.

History

Open Liberty originated as a descendant of projects maintained by IBM and was contributed to the Eclipse Foundation to form a community-driven runtime aligned with the Jakarta EE and Eclipse MicroProfile efforts. Early work drew on technologies from WebSphere Application Server and initiatives around Cloud Foundry and Docker containerization. Key milestones include integration with MicroProfile 1.0 and successive MicroProfile releases, alignment with the transition from Java EE to Jakarta EE under the Eclipse Foundation stewardship, and adoption by projects in the Cloud Native Computing Foundation ecosystem. Over time, contributions came from a mix of enterprises, academic groups, and independent developers, reflecting influences from Red Hat, Oracle Corporation, Google, Microsoft, and community contributors from universities and research labs.

Architecture and Components

Open Liberty is built as a modular runtime with small, composable features that are enabled or disabled at runtime. Core architectural elements include the server kernel, feature registry, and classloading subsystems, influenced by prior designs found in Apache Tomcat, Eclipse Jetty, and GlassFish. It supports runtime modules for Jakarta Servlet, Jakarta RESTful Web Services, and Jakarta Contexts and Dependency Injection drawing on specifications from the Eclipse Jakarta Project and the Jakarta EE Platform. The implementation integrates MicroProfile components such as MicroProfile Fault Tolerance, MicroProfile Metrics, and MicroProfile Config, and supports integration points with OpenTracing, OpenTelemetry, and Prometheus collectors. For persistence and data access, adapters exist for Jakarta Persistence API, Hibernate ORM, and drivers for PostgreSQL, MySQL, and MongoDB. The runtime exposes management APIs compatible with JMX and operational tooling used by Kubernetes operators and Helm charts.

Features and Standards Compliance

Open Liberty implements a broad set of standards, including Jakarta EE 9 and later specifications, and numerous Eclipse MicroProfile versions. Supported specifications include Jakarta Servlet 5.0, Jakarta RESTful Web Services 3.0, Jakarta Contexts and Dependency Injection 3.0, and Jakarta Transactions. On the MicroProfile side, it supports MicroProfile JWT Authentication, MicroProfile Health, MicroProfile OpenAPI, and MicroProfile Reactive Streams Operators. Compliance and certification efforts involved collaboration with organizations such as the Eclipse Foundation, Jakarta EE working groups, and vendors like IBM and Red Hat. It also adheres to interoperability tests influenced by Java Community Process artifacts and participates in compatibility testing with runtimes from Payara, WildFly, and Apache TomEE.

Deployment and Runtime Models

Open Liberty supports multiple deployment styles: embedded deployments for Spring Framework-style integration, traditional WAR/EAR deployment used in GlassFish-compatible workflows, and containerized deployments targeting Docker images orchestrated by Kubernetes. It provides production-ready runtime profiles designed for use with OpenShift clusters and integrates with continuous delivery pipelines driven by Jenkins, GitLab CI, and GitHub Actions. For cloud deployments, Open Liberty is used on Amazon Web Services, Microsoft Azure, and Google Cloud Platform with connectors for Cloud Foundry and support for Helm and Operator patterns. Runtime models include just-in-time feature loading, class isolation influenced by OSGi concepts, and native-image experiments leveraging GraalVM for ahead-of-time compilation.

Ecosystem and Tooling

A rich tooling ecosystem surrounds Open Liberty, including developer tools for local development such as the Eclipse IDE, Visual Studio Code, and IntelliJ IDEA extensions. Build integrations exist for Maven and Gradle, and CI/CD integrations include Travis CI historically, plus modern pipelines using CircleCI and Tekton. Observability tools in the ecosystem include Grafana, Prometheus, Zipkin, Jaeger, and OpenTelemetry Collector implementations. Vendors and projects that integrate with Open Liberty encompass IBM Cloud, Red Hat OpenShift, VMware Tanzu, HashiCorp Consul, and service mesh projects like Istio and Linkerd. Security tooling and vulnerability scanning connect with Snyk, Dependabot, and OSS-Fuzz-style initiatives.

Adoption and Use Cases

Open Liberty is used in enterprise applications, microservice architectures, and by research projects requiring modular Jakarta EE or MicroProfile runtimes. Adoption scenarios include transactional web applications in financial firms that also use Apache Kafka for event streaming, supply-chain platforms integrating SAP systems, and government digital services deployed on Azure Government or AWS GovCloud. Academic and research use includes collaborations with MIT, Stanford University, and other institutions exploring cloud-native middleware. Case studies often mention migration from WebSphere Application Server and GlassFish to reduce footprint and improve startup in containerized environments. Organizations using Open Liberty range from small startups to large enterprises such as HSBC, Barclays, and other firms in the Fortune 500 that prioritize Jakarta EE compatibility.

Security and Maintenance

Security practices for Open Liberty include timely patching, CVE monitoring coordinated with upstream projects like OpenSSL, Apache HTTP Server, and GNU C Library where relevant, and integration with vulnerability scanning services from CVE databases and vendors like Tenable and Qualys. The project follows maintenance cycles influenced by releases of Java SE from Oracle Corporation and the OpenJDK community, and coordinates updates with Jakarta EE specification changes. Operational security features include support for TLS 1.3 configurations, OAuth 2.0 and OpenID Connect authentication flows, and role-based access control compatible with Keycloak and Azure Active Directory deployments. Long-term support arrangements and commercial support are available through IBM and partners, while community support is facilitated via the Eclipse Foundation project governance and mailing lists.

Category:Java application servers