brutal-legends/src/reducers/index.js

import { combineReducers } from 'redux';
import albums from './albums';
import visibilityFilter from './visibility-filter';
import sortKey from "./sort-key";
import selectedAlbum from './selected-album';

export default combineReducers({
    albums,
    visibilityFilter,
    sortKey,
    selectedAlbum,
});