1 prototype chain

What this module drills

Every JavaScript object carries one hidden link to another object. Property reads follow that link; property writes don't. Almost everything else in the language — methods, inheritance, class, even Proxy — is built on that one asymmetry, and this module makes you feel it before you rely on it.

Why it bites

The word "prototype" names two different things: the hidden link an object has, and the .prototype property a function owns. Mix them up and you get code that runs, throws nothing, and silently does nothing — the kind of bug that survives code review. Koan 01 pulls the two apart; the rest build on the distinction.

Order

Work them in order — each one assumes the previous. 03 (a settings cascade with zero copying) is the payoff; 06 is a small capstone that ties the module together.

Run each file with Node, read the assertion that fails, fix the TODO, run again. Reveal the solution only after you have a passing run of your own.