Where does nullsafedev come from?
Void safety (also known as null safety) is a guarantee within an object-oriented programming language that no object references will have null or void values.
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Void safety is a static (compile-time) guarantee that a void call will never arise.1
Essentially when something is null safe it's reliable (in that you can reliably use / call it) and that's how I choose to describe myself - reliable.