A deep dive into how I use Terraform to automate cloud infrastructure, enforce security, and scale DevSecOps pipelines across AWS and Azure.

In the fast-paced world of cloud security, automation isn’t just a luxury — it’s a necessity. Over the past year, I’ve been deeply immersed in using Terraform to build, secure, and automate cloud infrastructure. As a Cloud Security Engineer and Architect, Terraform has become a critical part of my toolset, allowing me to enforce security by design, maintain consistency, and deploy with confidence across both AWS and Azure.

This article walks through everything I’ve been doing with Terraform — from infrastructure provisioning to advanced security automation and compliance enforcement.

1. Laying the Foundation: Secure VPC and Networking Setup

I started with building secure Virtual Private Clouds (VPCs) on AWS, including public and private subnets, NAT gateways, route tables, and internet gateways — all provisioned and maintained via Terraform.

Key Highlights:

  • Private Subnets with NAT Gateway for internet access without exposure
  • Elastic IPs for NAT Gateways to maintain consistent outbound IPs
  • Modular, tagged infrastructure with environment-based workspaces

2. IAM Automation: Principle of Least Privilege at Scale

Terraform has been instrumental in automating IAM across services.

What I did:

  • Created IAM roles for EC2, Lambda, and users with custom JSON-based policies
  • Applied least privilege principles
  • Made reusable IAM modules for rapid onboarding

3. EC2 Automation with User Data Scripts

Using Terraform, I configured EC2 instances that boot with secure configurations via user data.

Included in the automation:

  • Auto-assignment of static private IPs
  • Installation of security agents like CloudWatch, Fail2Ban, OSSEC
  • Bootstrapping cloud-init scripts managed via Terraform's templatefile()

4. Monitoring and Logging Integration

Security doesn't stop at provisioning — so I integrated CloudWatch and AWS Config to maintain visibility.

Provisioned resources:

  • CloudWatch log groups, metric filters, and alarms
  • AWS Config rules for continuous compliance
  • SNS alerts wired to email and Lambda functions

5. Automating Security Policies and Compliance

I leveraged Terraform to enforce security policies aligned with CIS Benchmarks and industry standards.

Automations include:

  • S3 buckets with public access blocked by default
  • AWS Security Hub with CIS AWS Foundations enabled
  • Multi-region CloudTrail with centralized logging

6. Infrastructure as Code for DevSecOps Pipelines

Security and DevOps go hand-in-hand. I integrated Terraform into CI/CD pipelines using GitHub Actions and Terraform Cloud.

Pipeline highlights:

  • PR-driven workflow with pre-merge security scans
  • IaC scanning tools like Checkov and Tfsec
  • Enforced remote state locking and team-based approvals

7. Multi-Cloud & Modularization

Though AWS is my primary platform, I’ve built Terraform modules for Azure networking and IAM, enabling future-proof hybrid cloud setups.

8. Real-World Projects

Here’s where I put Terraform into action:

  • Drauig BMS Security Architecture: Terraform-built secure cloud environment for AI border surveillance
  • Zero Trust Cloud Model: IAM, Lambda, and security group rules provisioned via Terraform
  • AWS Security Automation: Full deployment of Security Hub, GuardDuty, CloudTrail with Terraform

Conclusion: More Than Just Infrastructure

Terraform has transformed the way I work. From spinning up secure environments to embedding compliance into every deployment, it’s made infrastructure security code-driven, auditable, and scalable.

What’s Next?

I’m currently working on:

  • Publishing reusable Terraform modules on GitHub
  • Creating a free DevSecOps + Terraform workshop
  • Writing a hands-on guide to Terraform + AWS Security Hub

Let’s connect!

You can check out my portfolio at leonardkachi.github.io or follow me here on Dev.to.

Got questions or want to collaborate? Drop a comment below or message me — I'm always up for good DevSecOps talk.