Jenkins Pipeline – Overview
This section introduces Jenkins Pipelines, the core of modern Jenkins usage. Pipelines define how CI/CD flows are implemented as code.
What Is a Jenkins Pipeline?
A Jenkins Pipeline is a series of automated steps written in code that:
- Builds applications
- Runs tests
- Performs validations
- Deploys artifacts
Pipelines are defined using a Jenkinsfile stored in source control.
Why Pipelines Matter
Pipelines solve problems that older job types could not:
- UI-based configuration drift
- Poor visibility into changes
- Lack of reusability
- Weak scalability
With pipelines, you get:
- Pipeline as Code
- Version control
- Reviewable changes
- Reusable logic
- Consistent execution
Declarative vs Scripted Pipelines
Jenkins supports two pipeline syntaxes:
Declarative Pipeline
- Structured and opinionated
- Easier to read
- Safer defaults
- Recommended for most teams
Scripted Pipeline
- Fully Groovy-based
- Very flexible
- Harder to maintain
- Used only for advanced cases
Always start with Declarative.
What This Section Covers
You will learn:
- Jenkinsfile structure
- Stages vs steps
- Agent directive
- Environment and tools
- Basic pipeline control concepts
Each topic is documented in its own file.
Common Beginner Mistakes
- Writing pipeline logic in UI
- Mixing scripted logic unnecessarily
- Hardcoding environment values
- Ignoring pipeline readability
Interview Perspective
- Pipeline knowledge is mandatory
- Expect questions on Jenkinsfile structure
- Declarative vs Scripted comparison is common