From [NVRM's answer to this stackoverflow question](https://stackoverflow.com/questions/36258502/why-has-object-observe-been-deprecated)
```js
/* Simplest Object Observer */
Object.observe = (o, f) => new Proxy(o, { set: (a, b, c) => f(a, b, c) })

var obj = {
  foo: 0,
  bar: 1
};

// Assignment after creation, keep the variable name, extend.
obj = Object.observe(obj, function(target, prop, changes) {
  console.log("Change detected!", prop, changes)
})

obj.baz = 2;

obj.foo = 'hello';

/// EXAMPLES

```