Terraform Best Practices for Production Infrastructure

Terraform has become the standard for infrastructure as code, but adopting the tool is only the beginning. How you structure modules, manage state, and enforce policy determines whether your infrastructure scales gracefully or becomes a maintenance nightmare.

Modularize Everything

Build small, focused modules that do one thing well. A VPC module should create network resources — not also provision databases. Compose modules into higher-level abstractions for specific use cases. Version your modules and pin versions in production to avoid surprise changes.

State Management

Never store state locally. Use a remote backend with state locking — S3 with DynamoDB locking on AWS, or equivalent on other clouds. Separate state files by environment and by logical boundary to limit blast radius. Never edit state by hand.

Policy as Code

Use OPA or Sentinel to enforce policies before Terraform applies changes. Common policies include requiring encryption, disallowing public S3 buckets, enforcing tagging, and restricting instance types. Policies should be tested and versioned alongside your Terraform code.

GitOps for Infrastructure

Every infrastructure change should go through a pull request. Run terraform plan on the PR, post the plan as a comment, and require human approval before applying. This gives you an audit trail, peer review, and a safe rollback path — the same benefits GitOps brings to application deployments.