https://flow.org/en/docs/getting-started/ https://redux-observable.js.org/docs/basics/Epics.html
design principle in which custom-written portions of a computer program receive the flow of control from a generic framework. https://www.youtube.com/watch?v=-kpEP4JeEdc
https://reactjs.org/docs/higher-order-components.html
https://reactjs.org/docs/render-props.html https://www.youtube.com/watch?utm_campaign=React%2BNewsletter&utm_medium=web&utm_source=React_Newsletter_130&v=AiJ8tRRH0f8 14:35
https://blog.kentcdodds.com/the-state-reducer-pattern-%EF%B8%8F-b40316cfac57 https://www.youtube.com/watch?utm_campaign=React%2BNewsletter&utm_medium=web&utm_source=React_Newsletter_130&v=AiJ8tRRH0f8 14:45