# Defending the Cloud-Native Frontier: Security as Code with Terraform & OPA

Source: Dev.to

Overview

🚀 I just delivered a talk on “Security as Code: Enforcing AWS Security from Day One” to a group of 35+ cloud professionals. In today’s fast‑moving cloud environments, security can’t be an afterthought. The session showed how to build defense‑in‑depth by combining:

• Terraform – the foundation for consistent, repeatable infrastructure
• Open Policy Agent (OPA) + Conftest – to validate Terraform plans against custom security policies
• Automated guardrails that prevent misconfigurations before they reach production

Key Concepts

• Shift‑left security – make security an integral part of the Infrastructure‑as‑Code (IaC) pipeline rather than a separate compliance exercise.
• Security‑as‑Code – enforce policies through code, eliminating manual checklists.

Practical Scenarios

Blocking Unencrypted EBS Volumes

Prevent the creation of EBS volumes without encryption.

Restricting Overly Permissive Security Groups

Detect and reject security groups that allow inbound traffic from 0.0.0.0/0 on sensitive ports.

Enforcing Least‑Privilege IAM Roles

Validate that IAM roles grant only the permissions required for their function.

All these scenarios are enforced automatically during the Terraform plan phase.

Benefits

• Prevent misconfigurations before deployment – guardrails stop insecure resources from being provisioned.
• Ensure consistent security across environments – the same policies apply to dev, test, and prod.
• Enable developers to build securely from the start – security becomes part of the development workflow.
• Reduce compliance audit overhead – continuous policy enforcement provides audit‑ready evidence.

Resources

• Code examples, policies, and configurations:
  GitHub Repository

• Full presentation video:
  YouTube: Security as Code Talk

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Feel free to share the Security‑as‑Code practices you’ve implemented in your workflows in the comments below!