Example of storing data over hot reloads (using capaj/systemjs-hot-reloader)

getHotReloadStore.js

/**
 * Utility to store data over hot reloads.
 */

const globalStore = {};
export default function getHotReloadStore(key) {
  if (globalStore[key] === undefined) {
    globalStore[key] = {};
  }
  return globalStore[key];
}

Storing data over hot reloads

import getHotReloadStore from './utils/getHotReloadStore.js';
const hotStore = getHotReloadStore('d3d:store');

const state = hotStore.state || {
	counter: 0
};

console.log('state: ', state);
state.counter += 1;

hotStore.state = state;

Full example: https://github.com/peteruithoven/hot-reload-store-example