What it is

Jenkins is an open-source automation server built with Java and released under the MIT license. It lives in the continuous integration and continuous delivery ecosystem, where it has served as a central automation hub for roughly sixteen years. The project is developed in the open on GitHub, where it has accumulated 26,546 stars and 9,833 forks, and it is distributed through the official jenkins.io website alongside documentation, plugin listings, and release notes. Two release lines are maintained: a weekly line that carries all new features, improvements, and bug fixes, and a Long-Term Support line that receives periodic updates through bug fix backports.

The concrete problem Jenkins addresses is repetitive work in the software development lifecycle. Rather than having people manually build projects, run test suites, perform static code analysis, and push deployments, Jenkins executes those tasks on a schedule or in response to code changes. Its plugin catalogue of more than 2,000 extensions means the automation surface is not limited to a fixed set of integrations, and the pipelines-as-code approach, expressed through Groovy, lets teams keep their build and delivery definitions in version control next to the code they describe. The stated goal is that humans spend their time on work machines cannot do.

Key capabilities

• Automates building projects, running tests, performing static code analysis, and deploying software.
• Provides over 2,000 plugins for integrating with external tools and services.
• Supports pipelines-as-code, with Groovy as the associated language for defining pipelines.
• Ships in two release lines: weekly for new features and Long-Term Support for backported bug fixes.
• Distributes as WAR files, Docker images, native packages, and installers for several Linux distributions and Windows.
• Holds the CII Best Practices badge and reports reproducible builds.
• Detects bugs and other issues as soon as they are introduced, through automated test execution.

Who uses it and how

• Teams automating a development workflow so that repetitive build, test, analysis, and deployment tasks run without manual intervention.
• Projects that need continuous integration triggered by code changes, with test results surfaced early in the cycle.
• Organisations deploying to mixed infrastructure, using the native packages and installers for Linux distributions and Windows, or the Docker image where containers fit better.
• Groups that prefer declarative, version-controlled pipeline definitions written in Groovy rather than configuration held only in a user interface.
• Contributors and adopters who follow the project through its blog, website, and Matrix chat rooms, and who pick up issues labelled as good first issues.

Getting started

Official distributions are available as WAR files, Docker images, native packages, and installers for several Linux distributions and Windows, all referenced from the Downloads page at jenkins.io. Developers setting up a working environment are pointed to the contributing guide and the Jenkins Developer Documentation.

When to use it — and when not to

Jenkins suits teams that want a long-lived, plugin-extensible automation server they can run themselves and shape to unusual build and deployment requirements. The trade-off is operational: a self-hoster takes on running and upgrading the server, choosing between the weekly and LTS release lines, and keeping a large plugin surface current. The project carries 3,610 open issues, which reflects both its age and the breadth of its plugin ecosystem, and no hosted