Edited 2022:

Now you can just use stack.at(-1)

If you just need one edge of your stack (head or tail is not matter) use it reversed:

I mean :

peek() become array[0],
unshift(v) become push()
shift() become pop()

some code:

class Stack{
  constructor(... args ){
    this.store = [... args.reverse()];
  }
  peek(){
    return this.store[0];
  }
  push(value){
    return this.store.unshift(value);
  }
  pop(){
   return this.store.shift();
  }
}

const stack = new Stack(1,2,3);
stack.push(4);
console.log(stack.peek());
stack.pop();
console.log(stack.peek())

or shorter

function Stack(...rest){
  var store = [... rest.reverse() ];
  return {
    push:(v)=> store.unshift(v) ,
    pop : _ => store.shift(),
    peek: _ => store[0]
    }
  }
  
var stack = Stack(1,2,3);
console.log(stack.peek());
stack.push(4);
console.log(stack.peek());
stack.pop(), stack.pop();
console.log(stack.peek());