The real reason your staging environment is always broken

The real reason your staging environment is always broken "Don't trust staging" is engineering folklore. Teams treat it as inevitable. It's not — it's a symptom. What actually causes staging drift 1. Manual setup at different times : Prod Q1, staging Q3. Different engineers, different patterns. Identical at the start. Diverging ever since. 2. Hotfix culture : Prod incident at 2 AM. IAM permission patched in the console. Terraform state doesn't know. Staging doesn't have the patch. 3. Cost pressure on non-prod : "We don't need the full setup in staging." Different ALB, smaller RDS, different security groups. "Close enough" becomes "completely different." 4. Nobody owns staging : Prod has on-call. Staging has... whoever notices it's broken. The fix: same module, different vars # prod module "payment_service" { source = "../../modules/service" ; environment = "prod" instance_count = 3 ; db_class = "db.r6g.large" } # staging — SAME MODULE module "payment_service_staging" { source = "../../