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Jenkins — CI/CD Server

Jenkins is an extensible open-source automation server commonly used to build, test, and deploy software. Below are recommended patterns, a sample declarative Jenkinsfile, and security notes.

When to use Jenkins

  • Flexible pipelines that require many plugins or legacy integrations.
  • On-prem CI/CD where hosted runners are not an option.
  • Integrations with enterprise tooling (AD, artifact stores, custom agents).
  • Run Jenkins as a container or on a dedicated VM. Use persistent storage for JENKINS_HOME.
  • Use the recommended Kubernetes or Docker agent model for scalable builds.
  • Keep plugin set minimal and review plugin security advisories regularly.

Example: Declarative Jenkinsfile

pipeline {
    agent any
    environment {
        REGISTRY = 'myregistry.example.com/myteam'
    }
    stages {
        stage('Checkout') {
            steps { checkout scm }
        }
        stage('Build') {
            steps { sh 'docker build -t ${REGISTRY}/myapp:${GIT_COMMIT::8} .' }
        }
        stage('Test') {
            steps { sh 'pytest -q' }
            post { always { junit 'reports/*.xml' } }
        }
        stage('Scan') {
            steps { sh 'trivy image --exit-code 1 ${REGISTRY}/myapp:${GIT_COMMIT::8} || true' }
        }
        stage('Push') {
            when { branch 'main' }
            steps {
                sh 'docker push ${REGISTRY}/myapp:${GIT_COMMIT::8}'
            }
        }
    }
    post {
        success { echo 'Build succeeded' }
        failure { mail to: 'oncall@example.com', subject: "Build failed: ${env.JOB_NAME}", body: 'See Jenkins for details' }
    }
}

Security & best practices

  • Use credentials store for secrets (Jenkins Credentials), and avoid printing secrets in logs.
  • Limit who can create jobs and use role-based access control (RBAC) where possible.
  • Keep the Jenkins server and plugins up-to-date; enable CSRF protection and use TLS on the web UI.
  • Prefer ephemeral build agents (Kubernetes, Docker) over long-running agents.

If you'd like, I can add a sample Jenkinsfile in examples/jenkins/ and a short guide on setting up Jenkins on AKS or a VM.