sequence.js

import { queue, retry } from 'promise-frites';

const myApiCall1 = () => Promise.resolve()
  .then(() => { /* call server */ })
  .then(() => { /* notify user */}) 
  .then(() => { /* call server again */ })
  .then(() => { /* notify user again */});

const myApiCall2 = () => Promise.resolve()
  .then(() => { /* call server */ })
  .then(() => { /* notify user */});
  
Promise.resolve()
  .then(queue(...[myApiCall1, myApiCall2]));