terraform

dralgorhythm's avatarfrom dralgorhythm

Write Terraform infrastructure code. Use when provisioning cloud resources, managing infrastructure as code, or automating deployments. Covers HCL patterns.

⭐1stars🔀0forks📁View on GitHub🕐Updated Dec 20, 2025
[Cloud Infrastructure]

When & Why to Use This Skill

This Claude skill automates the creation and management of cloud resources through Terraform, the industry-standard Infrastructure as Code (IaC) tool. It enables developers to generate clean, modular HashiCorp Configuration Language (HCL) code, implement secure state management, and follow architectural best practices to ensure scalable, repeatable, and error-free cloud deployments.

Use Cases

  • Automated Multi-Tier Provisioning: Rapidly generate HCL configurations for complex cloud environments, including VPCs, private subnets, and EC2 instances with integrated data sources.
  • Infrastructure Modularization: Refactor monolithic infrastructure code into reusable modules to improve maintainability and promote standardized resource patterns across different projects.
  • CI/CD Workflow Automation: Streamline deployment pipelines by generating precise Terraform commands for initialization, validation, planning, and execution within automated environments.
  • State Management & Security: Implement enterprise-grade best practices such as remote S3 backends with DynamoDB locking, resource tagging, and strict provider versioning to prevent configuration drift.
nameterraform
descriptionWrite Terraform infrastructure code. Use when provisioning cloud resources, managing infrastructure as code, or automating deployments. Covers HCL patterns.
allowed-toolsRead, Write, Edit, Bash, Glob, Grep

Terraform Development

Project Structure

terraform/
├── main.tf           # Main resources
├── variables.tf      # Input variables
├── outputs.tf        # Output values
├── providers.tf      # Provider config
├── versions.tf       # Version constraints
├── terraform.tfvars  # Variable values
└── modules/
    └── vpc/
        ├── main.tf
        ├── variables.tf
        └── outputs.tf

Provider Configuration

# versions.tf
terraform {
  required_version = ">= 1.5"

  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 5.0"
    }
  }

  backend "s3" {
    bucket         = "terraform-state"
    key            = "prod/terraform.tfstate"
    region         = "us-east-1"
    dynamodb_table = "terraform-locks"
    encrypt        = true
  }
}

provider "aws" {
  region = var.aws_region

  default_tags {
    tags = {
      Environment = var.environment
      ManagedBy   = "terraform"
    }
  }
}

Variables

# variables.tf
variable "environment" {
  description = "Environment name"
  type        = string

  validation {
    condition     = contains(["dev", "staging", "prod"], var.environment)
    error_message = "Environment must be dev, staging, or prod."
  }
}

variable "instance_config" {
  description = "EC2 instance configuration"
  type = object({
    instance_type = string
    ami_id        = string
    volume_size   = number
  })

  default = {
    instance_type = "t3.micro"
    ami_id        = "ami-12345678"
    volume_size   = 20
  }
}

Resources

# main.tf
resource "aws_vpc" "main" {
  cidr_block           = var.vpc_cidr
  enable_dns_hostnames = true

  tags = {
    Name = "${var.project}-vpc"
  }
}

resource "aws_subnet" "private" {
  count             = length(var.availability_zones)
  vpc_id            = aws_vpc.main.id
  cidr_block        = cidrsubnet(var.vpc_cidr, 8, count.index)
  availability_zone = var.availability_zones[count.index]

  tags = {
    Name = "${var.project}-private-${count.index + 1}"
  }
}

Modules

# Using a module
module "vpc" {
  source = "./modules/vpc"

  project     = var.project
  environment = var.environment
  cidr_block  = "10.0.0.0/16"
}

# Module outputs
output "vpc_id" {
  value = module.vpc.vpc_id
}

Data Sources

data "aws_ami" "amazon_linux" {
  most_recent = true
  owners      = ["amazon"]

  filter {
    name   = "name"
    values = ["amzn2-ami-hvm-*-x86_64-gp2"]
  }
}

resource "aws_instance" "web" {
  ami           = data.aws_ami.amazon_linux.id
  instance_type = var.instance_type
}

Workflow

# Initialize
terraform init

# Format
terraform fmt -recursive

# Validate
terraform validate

# Plan
terraform plan -out=tfplan

# Apply
terraform apply tfplan

# Destroy
terraform destroy

Best Practices

  1. Use remote state with locking
  2. Use modules for reusability
  3. Use variables for all configurable values
  4. Use data sources for existing resources
  5. Tag all resources
  6. Use workspaces or directories for environments