Stages in a Jenkins pipeline are logical blocks that represent distinct phases of your CI/CD process, such as build, test, and deploy, allowing you to organize, visualize, and control the execution of tasks
In Jenkins, a pipeline stage is a fundamental building block that represents a distinct phase in your software delivery process. Stages divide your pipeline into logical units of work, making complex automation workflows more organized, readable, and maintainable. Each stage typically performs a specific function like compiling code, running tests, or deploying to an environment. The official Jenkins documentation describes the most basic continuous delivery pipeline as having at least three stages: Build, Test, and Deploy.
Stages serve multiple purposes in a Jenkins pipeline. They provide visualization in the Jenkins UI, showing exactly which phase succeeded or failed and how long each took. Stages also enable conditional execution, allowing you to run certain stages only when specific conditions are met, such as deploying only on the main branch. Additionally, stages help with error isolation—if a stage fails, the pipeline can stop at that point without executing later stages, saving time and resources.
Build Stage: Compiles source code, resolves dependencies, and creates artifacts. Typically runs commands like
mvn compile,gradle build, ornpm run build.Test Stage: Executes automated tests including unit tests, integration tests, and quality checks. Often includes code coverage analysis and static code analysis.
Deploy Stage: Delivers the built application to target environments such as development, staging, or production servers.
Environment-Specific Stages: Extended stages for different deployment targets, like 'Deploy - Staging' followed by 'Deploy - Production', often with approval gates between them.
Parallel Stages: Multiple stages that execute simultaneously to speed up the pipeline, such as running unit tests and integration tests concurrently.
Jenkins pipelines support different execution patterns for stages. Sequential stages execute one after another in the order defined, ensuring dependencies are satisfied. Parallel stages run multiple independent stages simultaneously, significantly reducing overall pipeline duration—for example, running cross-platform tests on Windows and Linux at the same time. Conditional stages only execute when specific criteria are met, such as running only on certain branches or when specific environment variables are set.
Stages can include advanced controls like input steps that pause the pipeline for manual approval, particularly between environment stages like promoting from staging to production. Post-stage actions defined in post blocks can send notifications, clean up resources, or archive artifacts based on the stage result. Stages can also access tools, define environment variables, and execute complex Groovy logic for sophisticated workflow requirements.