Continuous Integration and Delivery

Scenario: A team integrates long-lived branches on release day and cannot separate integration defects from release failures.

Pipeline example

pipeline { agent any; stages { stage('Build') { steps { sh './build.sh' } }; stage('Test') { steps { sh './test.sh' } } } }

Integration is a feedback contract

Continuous integration is a team behavior before it is a Jenkins feature. Developers merge small changes into a shared mainline frequently, and every accepted revision receives an automated build and meaningful tests. A green run says only that the encoded checks passed for one recorded revision; it does not prove untested behavior correct. Short-lived branches reduce the number of interactions that must be untangled after a failure.

Continuous delivery adds a repeatable path that leaves every successful change releasable. Continuous deployment is the separate policy choice to release every qualifying artifact automatically. A team can practice delivery while retaining a production approval, change window, or regulated separation of duties. That approval must promote an already-tested digest. Rebuilding the branch after approval creates new bytes and severs the evidence chain between test and release.

Measure and repair the loop

Map the SCM event, checkout, dependency resolution, compilation, tests, package publication, policy gate, promotion, rollout, and verification. Carry an immutable revision and artifact identity across every boundary. Measure commit-to-result latency, queue delay, execution duration, time spent red, and flaky-test frequency. Optimizing total build time while changes wait forty minutes for an executor does not improve feedback.

When release day reveals weeks of integration defects, shorten branch lifetime and move representative checks earlier. When tests are flaky, preserve the first failure, assign an owner, and quarantine only with an expiry; repeated retries teach teams to ignore red. A mature delivery loop makes a failed revision reproducible, a passed package identifiable, and every production decision explainable without relying on somebody's workstation or memory.

Goal: Practice the concrete behavior in jenkins-declarative-rescue. Learn sections have no Jenkins terminal; the Jenkins lab opens the real shared service in a new full-screen tab inside your private folder.