Azure Container Apps (ACA)
What it is
Azure Container Apps is a fully managed, serverless container computing service. You deploy containers (Docker images) without provisioning or managing Kubernetes infrastructure — Azure runs the platform. It sits in the compute spectrum between single-container Container Instances and full-blown AKS.
Why it exists
Running container workloads on AKS gives maximum control but costs real operational overhead (you manage the cluster). For many apps — HTTP microservices, background jobs, event-driven workloads — you don’t want to run a cluster at all. Azure Container Apps gives you managed Kubernetes scale without the Kubernetes operations burden.
Key ideas
- Serverless & fully managed — no cluster to create, patch, or scale. Pay for compute only when requests/tasks run.
- Auto-scaling per container app — scales up/down based on traffic, triggers, or schedule, automatically, unlike manually sizing a VM or tuning a cluster.
- Runs on Kubernetes underneath, but you never manage it. This is the core distinction from aks.
- Dapr integration — a built-in, portable microservices programming model for state management, pub/sub messaging, and service invocation (state-driven workflows).
- Revisions — each deployment of your containers produces a revision; you can roll back quickly between revisions.
- Use cases — single-page/HTTP API backends, background processors, event-streaming consumer apps, and workloads that mix HTTP + event handling.
ACA vs AKS vs ACI (memorize!)
| Service | Control | Who manages cluster |
|---|---|---|
| **[[aci | ACI]]** | Single containers, temporary tasks |
| Azure Container Apps | Microservices + auto-scale, no K8s admin | You manage no cluster |
| **[[aks | AKS]]** | Full Kubernetes control |
Container Apps is the pragmatic middle: you get Kubernetes power and auto-scaling without running Kubernetes.
Exam notes
- ACA ≠ ACI: ACI hosts a single independent container; ACA hosts container-based applications with lifecycle, revisions, and automatic scaling.
- ACA ≠ AKS: AKS requires you to manage a cluster; ACA is serverless and abstracts the cluster away.
- Likely to be compared in the exam against ACI, AKS, and Functions — knowing the control axis is the core discriminator.
Related
aci · aks · azure-functions · app-service · acr · app-service-plan