diff --git a/src/client/index.jsx b/src/client/index.jsx
index 92d0d60a..de32ee85 100644
--- a/src/client/index.jsx
+++ b/src/client/index.jsx
@@ -2,24 +2,21 @@ import { unmountComponentAtNode, render as reactRender } from 'react-dom';
 import { syncHistoryWithStore } from 'react-router-redux';
 import { browserHistory } from 'react-router';
 import { useBasename } from 'history';
-import { install as installSourceMapSupport } from 'source-map-support';
 import RedBox from 'redbox-react';
 import { Resolver } from 'react-resolver';
 
-/* eslint-disable import/no-extraneous-dependencies */
+/* eslint-disable import/no-extraneous-dependencies,import/newline-after-import,import/first */
+// used require instead of import, because optional default with import cause warnings
+const reducers = require('__app_modules__redux_reducers__');
 import routes from '__app_modules__routes__';
-import * as reducers from '__app_modules__redux_reducers__';
 import middlewares from '__app_modules__redux_middlewares__';
 import { parse as stateParser } from '__app_modules__redux_stateSerializer__';
-/* eslint-enable import/no-extraneous-dependencies */
+/* eslint-enable import/no-extraneous-dependencies, import/newline-after-import */
 
 import { create as createStore, createRootReducer } from '../shared/store';
 import config from '../../config';
 import App from './components/App';
-
-if (process.env.NODE_ENV !== 'production') {
-    installSourceMapSupport({ environment: 'browser' });
-}
+/* eslint-enable import/first */
 
 function render(history, store, appRoutes, element) {
     const insertCss = ({ _insertCss }) => _insertCss();
diff --git a/src/server/middlewares/store.js b/src/server/middlewares/store.js
index 6d0c6a9c..f70cbdcb 100644
--- a/src/server/middlewares/store.js
+++ b/src/server/middlewares/store.js
@@ -1,10 +1,16 @@
 import { createMemoryHistory } from 'react-router';
+
 /* eslint-disable import/no-extraneous-dependencies */
-import * as reducers from '__app_modules__redux_reducers__';
 import middlewares from '__app_modules__redux_middlewares__';
+// used require instead of import, because optional default with import cause warnings
+const reducers = require('__app_modules__redux_reducers__');
 /* eslint-enable import/no-extraneous-dependencies */
+
+
+/* eslint-disable import/first */
 import { create as createStore } from '../../shared/store';
 import config from '../../../config';
+/* eslint-enable import/first */
 
 export default () => (ctx, next) => {
     const history = createMemoryHistory({