Short, honest write-ups of the ideas that come up in interviews and on the job. Each one teaches the concept properly, cites the Microsoft documentation, and points back to the class that drills it until it sticks.
Declarative state, idempotency and state files — the three concepts tutorials skip — plus where Bicep, Terraform and Ansible each belong and a six-week path to a setup that survives other people touching it.
The moment your Bicep grows past a toy, one giant file becomes unreadable and you start pasting the same block everywhere. Modules are how infrastructure-as-code learns what every programmer knows: factor it into reusable functions.
Terraform's state file is the ledger of everything it built — and by default it sits on one person's machine. In a team, that is a corruption or a deleted file away from disaster. The fix is a remote backend in Azure Storage.
You may never write one by hand — Bicep spared you — but ARM templates are the native language Azure deployments actually speak. Knowing what they are makes everything above them make sense.
One is Azure's own language, stateless and native. The other is the multi-cloud standard that keeps a ledger of everything it built. An honest comparison — and why the choice is rarely a religion.