Jenkins Interview Questions

Both are pipeline-as-code in a Jenkinsfile. Declarative has a fixed, validated structure (pipeline, agent, stages, steps, post) and is the default choice. Scripted is plain Groovy, more flexible but harder to read and maintain. Use declarative and drop into a script block only when you must.

Have the runner write JUnit XML, publish it in a post { always } block with the junit step, and archive HTML reports, screenshots and traces as artifacts. The junit step marks the build UNSTABLE when tests fail; FAILURE means the pipeline itself broke, such as a compile error or crash.

Split the suite into shards, run each shard in a parallel stage on its own agent (labels or Kubernetes/Docker agents), stash the build once and unstash it per shard, publish every shard's JUnit XML, and use failFast deliberately. Balance shards by historical duration and keep tests independent.