mobx-react-hook

app.tsx

const WithJustAutoRun = React.memo((props: {
  first: Todo;
  second: Todo;
  counter: number;
}) => {

  const rendered = useObservation(() => {
    return (
      <div>
        <h1>
          Obs: {props.counter.toString() + props.first.completed.toString()}
        </h1>
      </div>
    );
  }, [props]);
    
  return <div>{rendered}</div>;
})

lib.tsx

const useObservation = (
  render: () => JSX.Element,
  dependencies: React.DependencyList = []
) => {
  const ref = useRef<JSX.Element>();
  const [tick, setTick] = useState(0);

  useEffect(() => {
    return autorun(() => {
      ref.current = render();
      setTick(tick + 1);
    });
  }, dependencies);
    
  return ref.current;
};