Create-React-App failed to compile | Import/First Error

For me, it was a case, because I was violating Eslint import/first rule, by calling an imported function before any other import.

For example, this code had a problem:

import configureStore from './redux/common/configureStore';
const store = configureStore();

// Add polyfill for fetch for older browsers
import 'isomorphic-fetch';
require('es6-promise').polyfill();

because I was calling and assigning const store = configureStore(); before import 'isomorphic-fetch';

This is because you accidentally installed React Router into src folder. So the linter thinks it’s your code and tries to validate it. Don’t install third party dependencies inside src.

Delete src/node_modules and run npm install in the root folder of your app. If some package is missing, run npm install --save <package-name>, also in the root folder.