GitHub Actions + Azure Container Instances: A Hands-On CI/CD Pipeline

I spend a lot of time architecting production Kubernetes environments on AKS, but I often get asked by teammates: "Where do I even start with containers and CI/CD?" This post is my answer to that. It's a complete lab start to finish that covers containerizing a simple web app, pushing it to Azure Container Registry, and wiring up a GitHub Actions workflow that automatically deploys to Azure Container Instances on every push. No click-ops, no manual FTP uploads, just a clean automated pipeline. The whole thing should take you around 40–50 minutes on first run. Why ACI and Not AKS? Fair question. In production, I'd use AKS for anything serious. But ACI is genuinely perfect for demos, dev environments, and internal tooling it's serverless containers with zero cluster overhead. You push an image, Azure runs it. That simplicity makes it an ideal first step for people wrapping their head around the CI/CD loop. What We're Building Here's the pipeline: A minimal Node.js web app (HTML/CSS/JS, n