🛠️ A People’s History of CI/CD

David Beale

— 2 min read

From Jenkins pipelines to GitHub Actions to AI-piloted deploys — how we got here, what we’ve learned, and what comes next.

☠️ Jenkins Will Outlive Us All

Every DevOps engineer has had at least one tour of duty in Jenkins. Some of us never made it out.

Born as Hudson in the early 2000s, Jenkins was built in an era when “CI” meant “run this cron job and pray.” It became the de facto automation engine for the open-source world — not because it was elegant, but because it was there, it was free, and you could write Groovy scripts until your fingers bled.

Jenkins was duct tape. Jenkins was freedom. Jenkins was pain.
And Jenkins... is still everywhere.

🛤️ Continuous Integration: The Assembly Line for Nerds

CI was the first domino.
The idea was simple:

  • Catch bugs early
  • Reduce merge hell
  • Automate tests
  • Build faster

And we got... Jenkinsfiles.
Shell scripts pretending to be pipelines.
Pipelines pretending to be applications.
An entire generation of engineers who learned YAML before learning how to code.

But hey — it worked.

🧪 The SaaS CI Boom

As cloud-native tooling matured, hosted CI/CD services exploded.

CircleCI simplified pipeline syntax and build isolation.
GitHub Actions turned your repo into a platform — CI workflows in .yaml, tightly integrated with your pull requests.
GitLab CI/CD said “why not just bake it all into your git server?”
Each took a piece of Jenkins' kingdom — one layer at a time.

And then came Harness, Buildkite, Semaphore, and friends — turning CI/CD into a full-blown SaaS arms race.
Abstracted pipelines. Feature flags. Rollbacks. Metrics.
CI wasn’t just automation anymore — it was productized.

🚀 Enter Continuous Deployment

CI solved the “does it build?” problem.
CD asked the real question:
“Can we ship this to prod without waking up the on-call?”

Tools like Spinnaker brought deployment orchestration to the fore — especially in complex cloud-native environments.
But Spinnaker was heavy. Complex. You almost needed a team just to run the tool that ran your deployments.

Then came the next wave...

🌊 GitOps, Argo, Flux, and the K8s Renaissance

When Kubernetes became the standard, Git became the truth.

  • Argo CD turned your Git commits into production changes
  • Flux CD watched your repos like a hawk and synced your clusters
  • Helm charts took over the world (for better or worse)

Suddenly, CD wasn’t just a tool — it was a philosophy.
Declare everything. Automate everything. Drift is the enemy.

🤖 The Future: AI-Assisted CI/CD?

Let’s not kid ourselves — LLMs are already doing PR reviews and writing tests.
What happens when they start:

  • Writing deployment pipelines?
  • Recommending rollback thresholds?
  • Auto-tuning canary rollouts?
  • Summarizing failed builds with natural language + fixes?

We're entering a world where you won’t write pipelines — you’ll describe intent.

“Ship this Go app with zero downtime and auto-scale it based on real user traffic.”

And the system will do the rest.

🔥 What We Lose If We Forget

But here’s the thing:
You can’t automate what you don’t understand.

CI/CD isn’t just a toolchain. It’s a reflection of how you think about software delivery.
If we let AI take the wheel without learning to drive, we’ll recreate all the old problems — just faster.

The past matters:

  • Jenkins taught us resilience
  • CircleCI taught us abstraction
  • Spinnaker taught us orchestration
  • GitOps taught us trust in version control
  • GitHub Actions taught us how to meet devs where they live
  • And now AI might teach us... empathy?
    Or maybe just how to deploy a service without screaming at Slack.

🧬 The Next Layer

The next generation of CI/CD will be:

  • Declarative
  • Intelligent
  • Self-correcting
  • Predictive

But it’ll still need us.
People who know why build caches matter.
People who remember when a test suite took 45 minutes.
People who write systems with graceful failure in mind.

Final Word

CI/CD isn’t dead. It’s just getting smarter.
But don’t let the tools think for you. Learn from the Jenkins scars. Trust, but verify.
And always, always write good commit messages.

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