Terraform: Infrastructure as Code Across Clouds

HashiCorp Terraform brings declarative infrastructure management supporting AWS, Azure, GCP, and on-premise. Why IaC is the future and how to get started with Terraform.

Why Infrastructure Needs Code¶

Clicking around in the AWS Console is fast for a prototype but unsustainable for production. Infrastructure as Code (IaC) brings the same principles to infrastructure management as those we apply to software development: versioning, code review, testing, and reproducibility.

Terraform by HashiCorp is an open-source tool that defines infrastructure in the declarative HCL (HashiCorp Configuration Language).

HCL and Terraform Workflow¶

The basic Terraform workflow is straightforward: write → plan → apply.

provider "aws" {
  region = "eu-west-1"
}

resource "aws_instance" "web" {
  ami           = "ami-0c55b159cbfafe1f0"
  instance_type = "t2.micro"

  tags = {
    Name = "web-server"
    Env  = "production"
  }
}

resource "aws_security_group" "web" {
  ingress {
    from_port   = 80
    to_port     = 80
    protocol    = "tcp"
    cidr_blocks = ["0.0.0.0/0"]
  }
}

terraform plan shows what will change. terraform apply executes the changes. The state file tracks the current state.

Multi-Cloud and Modularity¶

Terraform supports dozens of providers — AWS, Azure, GCP, DigitalOcean, CloudFlare, and many more. One tool for all clouds.

Modules enable reusable infrastructure components:

• Standardized VPC/VNET configurations
• Database clusters with built-in best practices
• Kubernetes clusters across clouds
• Monitoring and alerting stacks

State Management and Team Collaboration¶

Terraform state is critical — it contains the mapping between configuration and real resources. For teams, a remote state backend (S3, Consul, Terraform Cloud) with locking is essential.

Best practices:

• Remote state with encryption
• Small, focused state files (per environment/layer)
• Code review for all infrastructure changes
• terraform plan output in pull requests
• Gradually import existing infrastructure

Conclusion: IaC Is Not a Luxury, It Is a Necessity¶

Terraform brings software engineering discipline to infrastructure. For enterprise organizations with a multi-cloud strategy, it is a must-have tool. Start new projects in Terraform and gradually migrate existing infrastructure.