Terraform

• Gripping Terraform in Azure DevOps to build Infrastructure
• Azure DevOps Pipelines with Terraform and Stages
• Terraform Best Practices
• Terratest | Automated tests for your infrastructure code.
• Tools to Visualize your Terraform plan
• Octopus HCL Parser

Validation is quite handy:

Security issues with importing modules as you can reference a branch or tag:

git::https://your-module-url//modules/module_name?ref=somethingDodgyHere

Can also be imported from various other untrusted source (GitHub over HTTP)

Some code can execute during the plan stage of Terraform, usually unprotected.