Terraform makes it easy to stand up infrastructure and just as easy to create a tangled mess. A little structure early saves a great deal of pain later.
Compose with modules
Group related resources into small, reusable modules with clear inputs and outputs. Treat a module like a function: it should do one thing and be testable in isolation.
Respect your state
- Store state remotely with locking enabled.
- Separate state per environment to limit blast radius.
- Never edit state by hand unless you truly have no other option.
Plan before you apply, review the diff like you would review code, and your infrastructure changes become as boring and safe as a normal pull request.