( .parse('{}'), (root, path) => { // the root object that changed console.log(root); // the path that just changed console.log(path); } ); whatever'; data.array.value = [1, 2, 3]; data.array.value.push(4); // see all notifications about all changes JSON.stringify(data); // {"a":{"b":{"c":{"d":{"e":{"f":{"g":"whatever"}}}}}},"array":{"value":[1,2,3,4]}}