Jenkins

Jenkins is an open source CI/CD automation server that teams self-host to build, test and deploy code, extended through plugins.

Jenkins runs the build, test and deploy steps a team writes down, on servers and agents that the team operates itself. The project is part of the Continuous Delivery Foundation, with its assets held by Linux Foundation legal entities. It does not develop or distribute Jenkins for commercial purposes, and its source code is public on GitHub. Work is defined as a Pipeline, written in a Jenkinsfile that is stored and versioned beside the source code. The Declarative syntax offers Parallel and Matrix sections, cron and pollSCM triggers, and an input step that waits for named users or groups to approve a run. Multibranch Pipelines build each branch and validate pull requests through the GitHub and Bitbucket Branch Source plugins. Credentials are stored encrypted on the controller and masked in the console log, and Shared Libraries package common steps for many pipelines. Build output moves through the archiveArtifacts and stash steps, the junit step records test results, and plugins such as Job Cacher, Flaky Test Handler and OpenID Connect Provider add caching, flaky test handling and keyless cloud authentication. Jenkins suits platform and DevOps engineers who want CI/CD to run inside their own infrastructure rather than on a hosted service. It installs from a Docker image, on Kubernetes, on Linux, macOS or Windows, as a WAR file or as an offline installation. Organisations with many repositories can keep one set of Shared Libraries and one pool of agents for every team. There is no hosted edition, so a team downloads the software and runs its own controller and agents. A common setup checks out code from GitHub or Bitbucket, builds it with Maven or Gradle and runs the test suite on every pull request. As a continuous delivery hub, a pipeline builds a Docker image and pauses at an input step before the deploy stage runs. Nightly jobs start on a cron trigger, while agents on Linux, Windows and macOS let one pipeline test the same code on all three systems. Blue Ocean then shows each run as a stage graph beside its steps and logs. Jenkins fits teams that want the build server, its agents and its credentials under their own control.