// React-Redux
handleBrushMove(event) {
   const { start, end } = event.selection;

   // setChartSelection is a redux action,
   // modifies some shared state in Redux
   this.props.setChartSelection(start, end); 

  // Now controller and controlled component 
  // both use mapStateToProps to 
  // pull selection from Redux Store
}

// Create a thing that can be watched
// Convention to end observables with $
const chartSelection$ = new Subject();

// Inside your handler, stream can be injected
handleBrushMove(event) {
   const { start, end } = event.selection;
   chartSelection$.next({ start, end })
}

// Meanwhile, in another file...
chartSelection$.subscribe(selection => {
   const { start, end } = selection;
   minimap.moveTo(start, end);
})

// Add more subscriptions freely!
// Introduce throttle, debounce, merge (hotkeys) in a file
// decoupled from the rest of your charting logic...