Why CI/CD matters for development velocity in Jenkins - Why It Works

Introduction

Developers need to deliver software quickly and reliably. CI/CD helps by automating testing and deployment, so code changes reach users faster without breaking things.

When you want to catch bugs early by running tests automatically after every code change

When you want to deploy new features to users quickly without manual steps

When multiple developers work on the same project and need to merge changes safely

When you want to reduce manual errors in building and releasing software

When you want to get feedback fast on whether your code works as expected

Commands

Starts the Jenkins server locally so you can access the web interface to create CI/CD pipelines.

Terminal

java -jar jenkins.war

Expected Output

Running from: /home/user/jenkins.war

2024-06-01 12:00:00.000+0000 [id=1]    INFO    org.eclipse.jetty.server.Server#main: Started @12345ms

Jenkins is fully up and running

Triggers a build of the Jenkins pipeline named 'my-pipeline' to start the CI/CD process.

Terminal

curl -X POST http://localhost:8080/job/my-pipeline/build --user admin:admin123

Expected Output

Started build #1

→

-X POST - Specifies the HTTP method to trigger the build

→

--user admin:admin123 - Authenticates the request with Jenkins

Checks the status and result of the last build to see if tests passed and deployment succeeded.

Terminal

curl http://localhost:8080/job/my-pipeline/lastBuild/api/json --user admin:admin123

Expected Output

{"result":"SUCCESS","building":false,"number":1}

→

--user admin:admin123 - Authenticates the request with Jenkins

Key Concept

If you remember nothing else, remember: CI/CD automates testing and deployment so developers can deliver software faster and safer.

Common Mistakes

Not running tests automatically in the pipeline

This lets bugs slip through and slows down development because problems are found late.

Include automated test steps in the Jenkins pipeline to catch issues early.

Manually deploying code after build

Manual steps cause delays and increase risk of errors.

Automate deployment in the CI/CD pipeline to speed up delivery and reduce mistakes.

Not checking build status regularly

You might miss failed builds and deploy broken code.

Use Jenkins API or dashboard to monitor build results continuously.

Summary

Start Jenkins server to create and run CI/CD pipelines.

Trigger pipeline builds automatically to test and deploy code.

Check build results to ensure code quality and successful deployment.