Don't Turn Terraform Modules Into Black Boxes: IaC Layered Design Decisions and 6 Production Anti-Patterns Broken Down
Overview Last year I was setting up an IaC system for an e-commerce client. When I took over, their Terraform codebase looked roughly like this: three environments (dev/staging/prod), each with its own copy of the configuration, totaling over 3,000 lines—90% of which was copy-paste. Changing a VPC CIDR meant editing three files in sync. Miss one, and you get environment drift. The worst part: a security group rule was missing in prod for three months without anyone noticing....