Pure functions have no timing dependency issues.

no-timing-dependency.js

const x = {
  val: 2
};

const x1 = x => Object.assign({}, x, { val: x.val + 1});

const x2 = x => Object.assign({}, x, { val: x.val * 2});

console.log(x1(x2(x)).val); // 5


const y = {
  val: 2
};

// Since there are no dependencies on outside variables,
// we don't need different functions to operate on different
// variables.

// this space intentionally left blank


// Because the functions don't mutate, you can call these
// functions as many times as you want, in any order, 
// without changing the result of other function calls.
x2(y);
x1(y);

console.log(x1(x2(y)).val); // 5