createStore.js

import { compose, createStore as reduxCreateStore } from 'redux';

const reducer = state => {
  return state;
};

const initialState = {};
const windowGlobal = typeof window !== 'undefined' && window;
const devtools =
  process.env.NODE_ENV === 'development' && windowGlobal.devToolsExtension
    ? window.__REDUX_DEVTOOLS_EXTENSION__ &&
      window.__REDUX_DEVTOOLS_EXTENSION__()
    : f => f;

const createStore = () =>
  reduxCreateStore(reducer, initialState, compose(devtools));
export default createStore;