env property
Env is the registrar environment. It is the fact that decides whether money moves: only "prod" reaches the live, billable registrar — anything else, including unset, is the sandbox.
Please note: This property should have been non-nullable! Since the specification file does not include a default value (using the "default:" property), however, the generated source code must fall back to having a nullable type. Consider adding a "default:" property in the specification file to hide this note.
Implementation
String? env;