# Azure Functions

> Expert patterns for Azure Functions development including isolated worker model, Durable Functions orchestration, cold start optimization, and production patterns. Covers .NET, Python, and Node.js ...

- Skill: `rootcastleco/azure-functions` (Agent Skill)
- Install (CLI): `npx skillmds add rootcastleco/azure-functions`
- Raw SKILL.md: https://api.skillmd.com/api/skills/rootcastleco/azure-functions/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: DevOps & Infra
- Author: rootcastleco (https://skillmd.com/u/rootcastleco)
- Updated: 2026-09-08
- Page: https://skillmd.com/skills/rootcastleco/azure-functions

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# Azure Functions

## Patterns

### Isolated Worker Model (.NET)

Modern .NET execution model with process isolation

### Node.js v4 Programming Model

Modern code-centric approach for TypeScript/JavaScript

### Python v2 Programming Model

Decorator-based approach for Python functions

## Anti-Patterns

### ❌ Blocking Async Calls

### ❌ New HttpClient Per Request

### ❌ In-Process Model for New Projects

## ⚠️ Sharp Edges

| Issue | Severity | Solution |
|-------|----------|----------|
| Issue | high | ## Use async pattern with Durable Functions |
| Issue | high | ## Use IHttpClientFactory (Recommended) |
| Issue | high | ## Always use async/await |
| Issue | medium | ## Configure maximum timeout (Consumption) |
| Issue | high | ## Use isolated worker for new projects |
| Issue | medium | ## Configure Application Insights properly |
| Issue | medium | ## Check extension bundle (most common) |
| Issue | medium | ## Add warmup trigger to initialize your code |

## When to Use
This skill is applicable to execute the workflow or actions described in the overview.

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