Environment-specific variables in Terraform are often treated like switches.
Dev.
Prod.
Test.
But Terraform does not see environments.
It only sees identity and values.
In this lesson, we strip away the folder structures and naming conventions and look at how Terraform actually reasons. A variable is not an environment selector. It is an identity slot in the dependency graph. The environment exists only in the values supplied from outside that graph.
This distinction matters more than it first appears.
When a value changes, Terraform does not ask whether it is “safe.”
It asks whether the identity implied by the values still matches what it remembers.
Sometimes, the answer is no.
And when that happens, Terraform does not adjust.
It replaces.
The lesson also surfaces a critical risk that is often misunderstood. Sharing a state file across environments is not a minor mistake or a drift scenario. It is catastrophic. Terraform will remain internally consistent while your infrastructure is silently replaced.
This video avoids commands and workflows by design.
Instead, it trains you to predict Terraform’s decisions before they occur.
If you want to understand environment-specific variables as Terraform understands them, this lesson will recalibrate your mental model.
Watch the full lesson on YouTube.