CloudFormation — AWS Infrastructure as a Template

Terraform is multi-cloud. CloudFormation is AWS-only. Why would we want a vendor-specific tool? Because CloudFormation is native — drift detection, stack events, rollback, integration with every AWS service from day one.

Stacks and Templates¶

AWSTemplateFormatVersion: '2010-09-09'
Description: Web application stack

Resources:
  WebServer:
    Type: AWS::EC2::Instance
    Properties:
      ImageId: ami-0c55b159cbfafe1f0
      InstanceType: t2.micro
      SecurityGroupIds:
        - !Ref WebSecurityGroup
      Tags:
        - Key: Name
          Value: web-server

  WebSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Web server security group
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: 80
          ToPort: 80
          CidrIp: 0.0.0.0/0

Outputs:
  PublicIP:
    Value: !GetAtt WebServer.PublicIp

CloudFormation vs. Terraform¶

CF advantages: Native drift detection, automatic rollback on failure, stack events for auditing, no state file management. Terraform advantages: Multi-cloud, better HCL syntax, plan command, larger community of modules.

Our strategy: Terraform for multi-cloud and infrastructure, CloudFormation for AWS-specific services (Lambda, API Gateway, CloudFront) where CF has better support.

Both Tools Have Their Place¶

CloudFormation for deep AWS integration, Terraform for flexibility. The important thing is to have infrastructure as code — the specific tool is secondary.