iac-module-design

name	iac-module-design
description	Write composable Terraform/OpenTofu modules: single responsibility, typed variables with validation, documented outputs, for_each over count to avoid reorder churn, pinned provider requirements, and a working example.

IaC Module Design

One module, one job

Typed variable blocks + validation; documented outputs; a README with an example.

for_each, not count

count keys by index -> removing a middle element recreates the rest. for_each keys by a stable id -> no churn on reorder.

Pin

required_providers with version constraints in the module; commit the lock file at the root.

No secret leakage

Mark sensitive, source from a manager; never put a secret in an output (it lands in plaintext state).

Test

Examples that plan cleanly + module tests (terraform test / Terratest).