Terraform Skill for Claude

Comprehensive Terraform and OpenTofu guidance covering testing, modules, CI/CD, and production patterns. Based on terraform-best-practices.com and enterprise experience.

When to Use This Skill

Activate this skill when:

• Creating new Terraform or OpenTofu configurations or modules
• Setting up testing infrastructure for IaC code
• Deciding between testing approaches (validate, plan, frameworks)
• Structuring multi-environment deployments
• Implementing CI/CD for infrastructure-as-code
• Reviewing or refactoring existing Terraform/OpenTofu projects
• Choosing between module patterns or state management approaches

Don't use this skill for:

• Basic Terraform/OpenTofu syntax questions (Claude knows this)
• Provider-specific API reference (link to docs instead)
• Cloud platform questions unrelated to Terraform/OpenTofu

Core Principles

1. Code Structure Philosophy

Module Hierarchy:

Type	When to Use	Scope
Resource Module	Single logical group of connected resources	VPC + subnets, Security group + rules
Infrastructure Module	Collection of resource modules for a purpose	Multiple resource modules in one region/account
Composition	Complete infrastructure	Spans multiple regions/accounts

Hierarchy: Resource → Resource Module → Infrastructure Module → Composition

Directory Structure:

environments/        # Environment-specific configurations
├── prod/
├── staging/
└── dev/

modules/            # Reusable modules
├── networking/
├── compute/
└── data/

examples/           # Module usage examples (also serve as tests)
├── complete/
└── minimal/

Key principle from terraform-best-practices.com:

• Separate environments (prod, staging) from modules (reusable components)
• Use examples/ as both documentation and integration test fixtures
• Keep modules small and focused (single responsibility)