Why? You have 100ms to respond to user input before they notice a lag. RAIL
How:
- https://www.smashingmagazine.com/2016/11/true-lies-of-optimistic-user-interfaces/
- UX: https://uxplanet.org/optimistic-1000-34d9eefe4c05
- Meteor: http://dev.apollodata.com/react/optimistic-ui.html
- custom subscribe method in service
- RxJS
- event emitter: http://stackoverflow.com/questions/36076700/what-is-the-proper-use-of-an-eventemitter
- store: base-store.ts
- angular event: http://stackoverflow.com/questions/34700438/global-events-in-angular-2