| name | compute-host-selection |
| description | Decision playbook for choosing the right Azure compute service — App Service, Container Apps, Azure Functions, Static Web Apps, or AKS — based on workload shape, ops burden, and scaling requirements. |
Compute Host Selection
When to Use This Skill
Use when a new workload needs a home on Azure and the right compute service is not obvious, or when reviewing an existing workload that may be over- or under-engineered for its current host.
1. The Primary Decision Tree
Answer these questions in order:
| Question | If YES | If NO |
|---|
| Is it purely static (HTML/JS/CSS + optional serverless API)? | Static Web Apps | Continue |
| Is it event-driven, short-duration (< 10 min), and triggered by a queue/timer/HTTP? | Azure Functions | Continue |
| Does it need HTTP scaling to zero AND you want container-native packaging? | Container Apps | Continue |
| Does it need the full Kubernetes API (CRDs, operators, custom schedulers)? | AKS | Continue |
| Everything else (traditional web app, always-on API, background service) | App Service | — |
2. Service Comparison Table
| Service | Scale-to-zero | Container-native | Ops burden | Best for |
|---|
| App Service | No (always-on) | Optional | Low | Web apps, REST APIs, background workers |
| Container Apps | Yes (Consumption) | Yes | Low-medium | Microservices, event-driven containers, scale-to-zero HTTP |
| Azure Functions | Yes | Optional | Low | Event-driven, short-lived, trigger-based processing |
| Static Web Apps | Yes | No | Minimal | SPAs, static sites, Jamstack with optional API routes |
| AKS | No | Yes | High | Kubernetes-specific APIs, complex orchestration |
3. Hosting the Claude Application on Azure
Per app-platform-engineer's remit:
| Claude app shape | Recommended host |
|---|
| HTTP API wrapper around Claude | Container Apps (scale-to-zero, sidecar-friendly) |
| Serverless inference trigger | Azure Functions (Consumption plan, Durable for long chains) |
| Long-running agent with stateful conversation | Container Apps (min replicas: 1) or App Service |
| Full web app (front-end + API) | App Service (front-end) + Container Apps (API) |
Seam: claude-app-engineering names the target; this plugin provisions it.
4. App Service Plan SKU Selection
| Workload | SKU tier | Notes |
|---|
| Production web API | P2v3 or P3v3 | Zone-redundant available from P1v3+ |
| Dev / internal tools | B2 or B3 | No autoscale; acceptable for low-traffic |
| High-scale or zone-redundant | P2v3 + ZoneRedundant: true | Premium v3 required |
| Functions (always-on) | Elastic Premium EP2 | Needed when cold-start is unacceptable |
Avoid the Free and Shared tiers for anything beyond prototyping.
5. Container Apps Environment Considerations
resource containerAppsEnv 'Microsoft.App/managedEnvironments@2024-03-01' = {
name: 'cae-myapp-prod-eastus'
location: location
properties: {
zoneRedundant: true // prod only; not available in all regions
workloadProfiles: [
{
name: 'Consumption'
workloadProfileType: 'Consumption'
}
]
}
}
Use the Consumption workload profile for scale-to-zero. Use Dedicated (D4 / D8) for workloads needing guaranteed CPU/memory.
6. When to Use AKS (and When Not To)
Use AKS only when you need:
- Custom Kubernetes operators or CRDs
- Specific runtime scheduling (GPU node pools, spot nodes)
- Existing Kubernetes manifests and Helm charts from on-premises
Do not use AKS when:
- The requirement is "containerized" — Container Apps handles this with far less ops overhead
- The team doesn't have Kubernetes expertise — cluster upgrades, node pool management, and CNI configuration are non-trivial
- Cost is a concern — AKS system node pools run 24/7; Container Apps Consumption scales to zero
7. Checklist Before Finalizing
Pitfalls
- Defaulting to AKS because the team "uses Docker" — Container Apps covers 90% of container use cases without Kubernetes ops overhead
- Using the Consumption plan for Functions that must always be warm — use Elastic Premium
- Choosing App Service for scale-to-zero HTTP APIs — it doesn't scale to zero; use Container Apps
- Forgetting zone redundancy for prod workloads — outages in a single AZ take the service down
See Also
