Jenkins to GitHub Actions: My CI/CD Migration Journey

Over the past few months, our team embarked on a large-scale migration from Jenkins to GitHub Actions for all our CI/CD pipelines. While Jenkins served us well for years, the growing complexity of maintaining infrastructure and plugins made us reconsider. GitHub Actions offered an elegant, integrated solution that aligned with our evolving DevOps culture.

In this post, I’ll Walk you through why we made the switch, the lessons we learned, and how we successfully migrated 85+ deployment pipelines across three Jenkins instances—with zero downtime.

🧠 Why We Decided to Move on from Jenkins
Jenkins has been a powerhouse for CI/CD for over a decade. But as our infrastructure scaled, the manual upkeep and plugin dependency hell began to slow us down.

Here’s what pushed us to explore alternatives:

Frequent issues due to outdated or broken plugins

Overhead of maintaining three Jenkins servers

Complex Groovy-based pipelines that lacked readability

💡 Why GitHub Actions?
We evaluated a few options (GitLab CI, CircleCI, etc.), but GitHub Actions stood out for its:

✅ Key Benefits:
Simplicity: No more Java, no more plugin babysitting.

Native GitHub Integration: Works with our PRs, issues, releases, and teams.

YAML Pipelines: Clean, declarative, and version controlled.

Cost Efficiency: Generous free minutes (especially for public and small orgs).

Scalability: Built-in runners + easy self-hosted runners for custom needs.

🔍 Pre-Migration Planning
Before jumping in, we set clear goals and created a detailed inventory:

🗂️ Our Checklist:
✅ Repositories hosted on GitHub

✅ Identified Jenkins jobs to migrate (85+)

✅ Documented all secrets, env variables, and external dependencies

✅ Listed Jenkins plugins and shared libraries in use

✅ Defined success criteria: zero deployment disruptions

We also established a migration strategy—starting with lower-risk pipelines and ramping up.

🔧 The Migration Process
Here’s a breakdown of how we transitioned from Jenkins to GitHub Actions:

1. Create .github/workflows/ in each repo
   This is where all our GitHub Actions YAML files now live.

2. Convert Jenkins Pipelines
   We mapped Jenkins stages like this:

groovy
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pipeline {
agent any
stages {
stage('Build') { ... }
stage('Test') { ... }
stage('Deploy') { ... }
}
}
...to GitHub Actions:

yaml
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jobs:
build:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v3
- name: Build
run: npm run build

We also used GitHub Secrets and Environments to replace Jenkins credentials and global vars.

1. Add Reusable Marketplace Actions We replaced our custom Jenkins steps with reusable actions from GitHub Marketplace:

actions/setup-node

docker/build-push-action

actions/cache

slackapi/slack-github-action

These simplified our workflows significantly.

1. Optimize & Cache Performance is key—so we:

Used actions/cache for dependency caching

Split workflows into multiple jobs

Used matrix builds for testing across environments

1. Test, Debug, Repeat GitHub Actions’ live logs, annotations, and built-in debugging tools made testing surprisingly smooth. We also validated outputs by comparing them against Jenkins job results.

🔐 Security & Access Control
With GitHub Environments and Secrets, we achieved:

Scoped access to sensitive data

Approval gates for production deploys

Audit logs for all workflow changes

📈 Impact & Results
We successfully migrated:

✅ 85+ pipelines
✅ 3 Jenkins servers retired
✅ CI times reduced by ~30% on average
✅ Zero production incidents

But more importantly, developer experience improved dramatically. New team members now grok the CI/CD system in minutes, not days.

🧭 What We Learned
Start small. Migrate a simple pipeline first, then scale.

Automate secrets and environment setup early.

Don’t replicate Jenkins 1:1. Use this as a chance to improve workflows.

Monitor performance post-migration. GitHub’s workflow insights help a lot.

📌 Final Thoughts
This migration was more than a technical refactor—it was a step toward a more modern, scalable, and developer-friendly infrastructure. If you’re considering moving away from Jenkins, I can confidently say: GitHub Actions is ready.