How Conditionals Make Terraform Infrastructure Dynamic and Efficient

One Module, Two Environments, Zero Code Duplication Day 11 of the 30-Day Terraform Challenge — and today I learned that conditionals are the secret sauce that turns a rigid configuration into a flexible, environment-aware system. Yesterday I had a module that worked for dev. Today I have a module that works for dev, staging, AND production — all from the same codebase. No copy-pasting. No separate branches. Just one environment variable driving everything. The Problem: Hardcoded Values for Every Environment Before today, if I wanted different instance sizes for dev and production, I had to: # dev/main.tf instance_type = "t3.micro" min_size = 1 max_size = 3 # production/main.tf instance_type = "t3.medium" min_size = 3 max_size = 10 Same code. Different files. Change something? Update both places. Forget one? Inconsistent infrastructure. This works until you have 5 environments. Then it becomes a maintenance nightmare. The Solution: Centralized Conditional Logic with Locals Instead of sc