diff --git a/README.md b/README.md
index e648c9f..2c4cc57 100644
--- a/README.md
+++ b/README.md
@@ -31,7 +31,9 @@ $ npm i && make browser
 $ cd ../../..
 
 $ webpack -w
-$ DEBUG=1 electron app/
+$ electron app/
+$ DEBUG=1 electron app/ # with Developer toolbar
+$ DEBUG=1 REDUX=1 electron app/ # with Redux Developer toolbar
 ```
 
 
diff --git a/app/package.json b/app/package.json
index dda4f2e..3191292 100644
--- a/app/package.json
+++ b/app/package.json
@@ -21,5 +21,10 @@
     "react-router": "^2.0.1",
     "redux": "^3.3.1",
     "sqlite3": "^3.1.3"
+  },
+  "devDependencies": {
+    "redux-devtools": "^3.2.0",
+    "redux-devtools-dock-monitor": "^1.1.1",
+    "redux-devtools-log-monitor": "^1.0.9"
   }
 }
diff --git a/package.json b/package.json
index 95aa201..9cc4597 100644
--- a/package.json
+++ b/package.json
@@ -50,16 +50,13 @@
     "babel-preset-es2015": "^6.6.0",
     "babel-preset-react": "^6.5.0",
     "css-loader": "^0.23.1",
+    "electron-builder": "^3.5.0",
+    "electron-prebuilt": "^0.37.5",
     "node-sass": "^3.4.2",
-    "redux-devtools": "^3.1.1",
-    "redux-devtools-dock-monitor": "^1.1.0",
-    "redux-devtools-log-monitor": "^1.0.5",
     "sass-loader": "^3.2.0",
     "style-loader": "^0.13.1",
     "url-loader": "^0.5.7",
-    "webpack": "^1.12.14",
-    "electron-prebuilt": "^0.37.5",
-    "electron-builder": "^3.3.1"
+    "webpack": "^1.12.14"
   },
   "scripts": {
     "postinstall": "./node_modules/.bin/install-app-deps",
diff --git a/src/app.js b/src/app.js
index 530ed1b..2ca10f8 100644
--- a/src/app.js
+++ b/src/app.js
@@ -12,12 +12,17 @@ import {Provider} from 'react-redux'
 import MainLayout from './components/layout/Main'
 import MainPage from './components/page/Main'
 
-// import DevTools from './assets/js/DevTools'
+import DevTools from './assets/js/DevTools'
 
 import Player from './context/Player';
 
-// window._store = createStore(reducer, DevTools.instrument());
-window._store = createStore(reducer);
+console.log(process.env.REDUX);
+
+if (process.env.REDUX) {
+  window._store = createStore(reducer, DevTools.instrument());
+} else {
+  window._store = createStore(reducer);
+}
 
 Player.getInstance();
 
diff --git a/src/assets/js/DevTools.js b/src/assets/js/DevTools.js
index 4c20d69..7571939 100644
--- a/src/assets/js/DevTools.js
+++ b/src/assets/js/DevTools.js
@@ -1,4 +1,5 @@
 import React from 'react';
+import Immutable from 'immutable'
 
 // Exported from redux-devtools
 import { createDevTools } from 'redux-devtools';
@@ -7,6 +8,8 @@ import { createDevTools } from 'redux-devtools';
 import LogMonitor from 'redux-devtools-log-monitor';
 import DockMonitor from 'redux-devtools-dock-monitor';
 
+let selectDevToolsState = (state = {}) => Immutable.fromJS(state).toJS();
+
 // createDevTools takes a monitor and produces a DevTools component
 const DevTools = createDevTools(
   // Monitors are individually adjustable with props.
@@ -14,7 +17,7 @@ const DevTools = createDevTools(
   // Here, we put LogMonitor inside a DockMonitor.
   <DockMonitor toggleVisibilityKey='ctrl-h'
                changePositionKey='ctrl-q'>
-    <LogMonitor theme='tomorrow' />
+    <LogMonitor theme='tomorrow' select={selectDevToolsState} />
   </DockMonitor>
 );
 
diff --git a/src/components/layout/Main/index.js b/src/components/layout/Main/index.js
index 891a02b..61d8f04 100644
--- a/src/components/layout/Main/index.js
+++ b/src/components/layout/Main/index.js
@@ -1,7 +1,7 @@
 import './styles/style.scss'
 import React from 'react'
 import Controls from '../../widget/Controls'
-// import DevTools from '../../../assets/js/DevTools'
+import DevTools from '../../../assets/js/DevTools'
 
 class Layout extends React.Component {
   constructor() {
@@ -22,12 +22,11 @@ class Layout extends React.Component {
         </section>
 
         <div>
+          {process.env.REDUX ? <DevTools /> : false}
         </div>
       </div>
     )
   }
 }
 
-// <DevTools />
-
 export default Layout;
diff --git a/src/components/widget/AlbumList/index.js b/src/components/widget/AlbumList/index.js
index be287c5..6de7876 100644
--- a/src/components/widget/AlbumList/index.js
+++ b/src/components/widget/AlbumList/index.js
@@ -1,6 +1,7 @@
 //import './styles/style.scss'
 import React from 'react'
 import {connect} from 'react-redux'
+import I from 'immutable'
 
 import database from '../../../context/db'
 import utils from '../../../assets/js/Utils'
@@ -8,13 +9,6 @@ import utils from '../../../assets/js/Utils'
 class AlbumList extends React.Component {
   constructor() {
     super();
-
-    this.state = {
-      albums: []
-    };
-
-    // cache
-    this.albumsCovers = {};
   }
 
   /**
@@ -22,7 +16,7 @@ class AlbumList extends React.Component {
    *
    * @returns {Promise}
    */
-  getAlbumList(props) {
+  getAlbumList(selectedArtist) {
     const sql = `SELECT
                   playlist.album,
                   COUNT(playlist.title) AS tracks,
@@ -37,12 +31,9 @@ class AlbumList extends React.Component {
                 GROUP BY playlist.album`;
 
     return new Promise((resolve, reject) => {
-      const selectedArtist = props.store.selected.artist;
-
       database.open((db) => {
         db.all(sql, {$artist: selectedArtist}, function(error, results) {
           if (results) {
-            console.debug(results);
             resolve(results);
           } else {
             console.error(error);
@@ -63,17 +54,17 @@ class AlbumList extends React.Component {
   }
 
   render() {
-    let albumList = this.state.albums.map((value, index) => {
-      const classList = 'list-group-item ' + (this.props.store.selected.album === value.album ? 'active' : '');
-      const coverArt = this.getCoverAsURL(value.id, value.coverArt);
+    let albumList = this.props.library.get('albums').map((value, index) => {
+      const classList = 'list-group-item ' + (this.props.selected.get('album') === value.get('album') ? 'active' : '');
+      const coverArt = utils.getURLfromBlob(value.get('coverArt'));
 
       return (
-        <li className={classList} key={index} onClick={this.setSelectedAlbum.bind(this, value.album)}
-            title={value.album}>
+        <li className={classList} key={index} onClick={this.setSelectedAlbum.bind(this, value.get('album'))}
+            title={value.get('album')}>
           <img className="media-object pull-left" src={coverArt} width="50" height="50" />
           <div className="media-body">
-            <strong>{value.album}</strong>
-            <p>{value.tracks} songs</p>
+            <strong>{value.get('album')}</strong>
+            <p>{value.get('tracks')} songs</p>
           </div>
         </li>
       );
@@ -86,29 +77,29 @@ class AlbumList extends React.Component {
     )
   }
 
-  getCoverAsURL(id, coverData) {
-    return this.albumsCovers[id] || (this.albumsCovers[id] = utils.getURLfromBlob(coverData));
-  }
-
   componentWillReceiveProps(nextProps) {
-    if (this.props.store.selected.artist !== nextProps.store.selected.artist) {
-      this.getAlbumList(nextProps).then((data) => {
-        this.setState({
-          albums: data
+    const selectedArtist = nextProps.selected.get('artist');
+
+    if (this.props.selected.get('artist') !== selectedArtist) {
+      this.getAlbumList(selectedArtist).then((data) => {
+        this.props.dispatch({
+          type: 'SET_LIBRARY_ALBUMS',
+          value: data
         });
       });
     }
   }
 
   shouldComponentUpdate(nextProps) {
-    return this.props.store.selected.artist ||
-           (this.props.store.selected.artist !== nextProps.store.selected.artist);
+    return !I.is(this.props.library.get('albums'), nextProps.library.get('albums')) ||
+           !I.is(this.props.selected.get('album'), nextProps.selected.get('album'));
   }
 }
 
 const mapStatesToProps = (store) => {
   return {
-    store: store
+    selected: store.get('selected'),
+    library: store.get('library')
   }
 };
 
diff --git a/src/components/widget/ArtistList/AlbumCover.js b/src/components/widget/ArtistList/AlbumCover.js
index c0fdcf8..00e29d3 100644
--- a/src/components/widget/ArtistList/AlbumCover.js
+++ b/src/components/widget/ArtistList/AlbumCover.js
@@ -4,47 +4,33 @@ import utils from '../../../assets/js/Utils'
 class AlbumCover extends React.Component {
   constructor() {
     super();
-
-    this.albumsCovers = {};
-    this.state = {
-      covers: null
-    };
   }
 
   render() {
-    const covers = this.state.covers && this.state.covers.length ? this.state.covers : [null];
+    let covers = [];
+
+    for (let i = 1; i < 5; ++i) {
+      let cover = this.props.data.get(`coverArt${i}`);
+
+      if (cover) {
+        covers.push(cover);
+      }
+    }
+
+    covers = covers && covers.length ? covers : [null];
 
     return (
       <div>
         {covers.map((value, index) => {
-          const id = value ? `${this.props.id}${index}` : 0;
-          const cover = this.getCoverAsURL(id, value);
+          const cover = utils.getURLfromBlob(value);
           return <img key={index} className="media-object pull-left" src={cover} />
         })}
       </div>
     )
   }
 
-  getCoverAsURL(id, coverData) {
-    return this.albumsCovers[id] || (this.albumsCovers[id] = utils.getURLfromBlob(coverData));
-  }
-
-  componentWillReceiveProps() {
-  }
-
-  componentDidMount() {
-    let covers = [];
-    for (let i = 1; i < 5; ++i) {
-      let cover = this.props[`coverArt${i}`];
-
-      if (cover) {
-        covers.push(cover);
-      }
-    }
-
-    this.setState({
-      covers: covers
-    });
+  shouldComponentUpdate(nextProps) {
+    return !nextProps.data.equals(this.props.data);
   }
 
 }
diff --git a/src/components/widget/ArtistList/index.js b/src/components/widget/ArtistList/index.js
index 1e5f5de..641717a 100644
--- a/src/components/widget/ArtistList/index.js
+++ b/src/components/widget/ArtistList/index.js
@@ -2,6 +2,7 @@ import './styles/style.scss'
 
 import React from 'react'
 import {connect} from 'react-redux'
+import I from 'immutable'
 
 import AlbumCover from './AlbumCover'
 
@@ -10,10 +11,6 @@ import database from '../../../context/db'
 class ArtistList extends React.Component {
   constructor() {
     super();
-
-    this.state = {
-      artists: []
-    };
   }
 
   /**
@@ -37,7 +34,6 @@ class ArtistList extends React.Component {
       database.open((db) => {
         db.all(sql, (error, results) => {
           if (results) {
-            console.debug(results);
             resolve(results);
           } else {
             console.error(error);
@@ -58,16 +54,16 @@ class ArtistList extends React.Component {
   }
 
   render() {
-    let artistsList = this.state.artists.map((value, index) => {
-      let classList = 'list-group-item ' + (this.props.store.selected.artist === value.artist ? 'active' : '');
+    let artistsList = this.props.library.get('artists').map((value, index) => {
+      let classList = 'list-group-item ' + (this.props.selected.get('artist') === value.get('artist') ? 'active' : '');
 
       return (
-        <li className={classList} key={index} onClick={this.setSelectedArtist.bind(this, value.artist)}
-            title={value.artist}>
-          <AlbumCover {...value} />
+        <li className={classList} key={index} onClick={this.setSelectedArtist.bind(this, value.get('artist'))}
+            title={value.get('artist')}>
+          <AlbumCover data={value} />
           <div className="media-body">
-            <strong>{value.artist}</strong>
-            <p>{value.albums} albums</p>
+            <strong>{value.get('artist')}</strong>
+            <p>{value.get('albums')} albums</p>
           </div>
         </li>
       );
@@ -80,11 +76,14 @@ class ArtistList extends React.Component {
     )
   }
 
-  getListOfArtists() {
+  getListOfArtists(callback) {
     this.getPlayList().then((data) => {
-      this.setState({
-        artists: data
+      this.props.dispatch({
+        type: 'SET_LIBRARY_ARTISTS',
+        value: data
       });
+
+      callback && callback();
     });
   }
 
@@ -93,20 +92,26 @@ class ArtistList extends React.Component {
   }
 
   componentWillReceiveProps(nextProps) {
-    if (nextProps.store.libraryUpdated) {
-      this.getListOfArtists();
+    if (nextProps.libraryUpdated) {
+      this.getListOfArtists(() => {
+        this.props.dispatch({
+          type: 'LIBRARY_DID_UPDATE'
+        });
+      });
     }
   }
 
   shouldComponentUpdate(nextProps) {
-    return (!this.props.store.selected.artist ||
-            (this.props.store.selected.artist !== nextProps.store.selected.artist));
+    return !I.is(this.props.library.get('artists'), nextProps.library.get('artists')) ||
+           !I.is(this.props.selected.get('artist'), nextProps.selected.get('artist'));
   }
 }
 
 const mapStatesToProps = (store) => {
   return {
-    store: store
+    selected: store.get('selected'),
+    library: store.get('library'),
+    libraryUpdated: store.get('libraryUpdated')
   }
 };
 
diff --git a/src/components/widget/Controls/index.js b/src/components/widget/Controls/index.js
index 36209ea..4622375 100644
--- a/src/components/widget/Controls/index.js
+++ b/src/components/widget/Controls/index.js
@@ -81,7 +81,7 @@ class Controls extends React.Component {
 
 const mapStatesToProps = (store) => {
   return {
-    isPlaying: store.isPlaying
+    isPlaying: store.get('isPlaying')
   }
 };
 
diff --git a/src/components/widget/LibraryProcess/index.js b/src/components/widget/LibraryProcess/index.js
index c7b5808..a0a761f 100644
--- a/src/components/widget/LibraryProcess/index.js
+++ b/src/components/widget/LibraryProcess/index.js
@@ -71,7 +71,6 @@ class LibraryProcess extends React.Component {
 
       fse.walk(files)
         .on('data', (item) => {
-          console.log(item);
           if (!item.stats.isDirectory() && item.path.match(this.extensions)) {
             items.push(item.path);
           }
@@ -103,8 +102,6 @@ class LibraryProcess extends React.Component {
         };
 
         let onMetadata = (metadata) => {
-          console.log(metadata);
-
           const covertArt = metadata.coverArt ? metadata.coverArt.data : undefined;
 
           trackInfoCallback({
@@ -116,15 +113,13 @@ class LibraryProcess extends React.Component {
             diskNumber: metadata.diskNumber,
             trackNumber: metadata.trackNumber,
             coverArt: covertArt
-          });
+          }, callback);
 
           this.releaseResource(asset, {
             onError,
             onMetadata,
             onData
           });
-
-          callback();
         };
 
         /**
@@ -139,8 +134,6 @@ class LibraryProcess extends React.Component {
           }, 300);
         };
 
-        console.log(file, asset);
-
         asset.on('error', onError);
         asset.get('metadata', onMetadata);
         asset.once('data', onData);
@@ -164,7 +157,7 @@ class LibraryProcess extends React.Component {
     asset = null;
   }
 
-  writeToDB(fileInfo) {
+  writeToDB(fileInfo, callback) {
     this.db.run('INSERT INTO `playlist` VALUES (?, ?, ?, ?, ?, ?, ?, ?)',
       [null, fileInfo.artist, fileInfo.albumArtist, fileInfo.album, fileInfo.title, fileInfo.file, fileInfo.diskNumber,
         fileInfo.trackNumber], (error) => {
@@ -178,8 +171,9 @@ class LibraryProcess extends React.Component {
             if (error) {
               console.error(error);
             }
-          });
 
+            callback();
+          });
       });
   }
 
diff --git a/src/components/widget/SongList/SongListComponent.js b/src/components/widget/SongList/SongListComponent.js
index bbf3381..5d65b42 100644
--- a/src/components/widget/SongList/SongListComponent.js
+++ b/src/components/widget/SongList/SongListComponent.js
@@ -32,16 +32,15 @@ class SongListComponent extends React.Component {
 
     setTimeout(() => {
       this.player.play(file);
+    }, 300);
 
-      this.props.dispatch({
-        type: 'PLAY',
-        value: {
-          title: title,
-          file: file
-        }
-      });
-    }, 500);
-
+    this.props.dispatch({
+      type: 'PLAY',
+      value: {
+        title: title,
+        file: file
+      }
+    });
   }
 
   render() {
@@ -55,7 +54,7 @@ class SongListComponent extends React.Component {
             </tr>
           </thead>
           <TrackList
-            {...this.props}
+            data={this.props}
             setSelectTrack={this.setSelectTrack}
             playTrack={this.playTrack}
           />
diff --git a/src/components/widget/SongList/TrackItem.js b/src/components/widget/SongList/TrackItem.js
index 449b827..a94af8f 100644
--- a/src/components/widget/SongList/TrackItem.js
+++ b/src/components/widget/SongList/TrackItem.js
@@ -4,11 +4,11 @@ const TrackItem = (props) => {
   let classList = () => {
     var output = [];
 
-    if (props.selectedFile === props.trackInfo.file) {
+    if (props.selectedFile === props.trackInfo.get('file')) {
       output.push('selected');
     }
 
-    if (props.playingFile === props.trackInfo.file) {
+    if (props.playingFile === props.trackInfo.get('file')) {
       output.push('active');
     }
 
@@ -17,8 +17,8 @@ const TrackItem = (props) => {
 
   return (
     <tr onClick={props.onClick} onDoubleClick={props.onDoubleClick} className={classList()}>
-      <td>{props.trackInfo.trackNumber}</td>
-      <td>{props.trackInfo.title}</td>
+      <td>{props.trackInfo.get('trackNumber')}</td>
+      <td>{props.trackInfo.get('title')}</td>
     </tr>
   );
 };
diff --git a/src/components/widget/SongList/TrackList.js b/src/components/widget/SongList/TrackList.js
index 6d11f64..e2cb85e 100644
--- a/src/components/widget/SongList/TrackList.js
+++ b/src/components/widget/SongList/TrackList.js
@@ -6,14 +6,14 @@ import TrackItem from './TrackItem'
 const TrackList = (props) => {
   return (
     <tbody>
-      {props.trackList.map((value, index) => {
+      {props.data.trackList.map((value, index) => {
         return (<TrackItem
           key={index}
           trackInfo={value}
-          selectedFile={props.selectedFile}
-          playingFile={props.playingFile}
-          onClick={props.setSelectTrack.bind(this, value.title, value.file)}
-          onDoubleClick={props.playTrack.bind(this, value.title, value.file)}
+          selectedFile={props.data.selectedFile}
+          playingFile={props.data.playingFile}
+          onClick={props.setSelectTrack.bind(this, value.get('title'), value.get('file'))}
+          onDoubleClick={props.playTrack.bind(this, value.get('title'), value.get('file'))}
         />);
       })}
     </tbody>
diff --git a/src/components/widget/SongList/index.js b/src/components/widget/SongList/index.js
index f3970ee..88c563b 100644
--- a/src/components/widget/SongList/index.js
+++ b/src/components/widget/SongList/index.js
@@ -1,5 +1,6 @@
 import React from 'react'
 import {connect} from 'react-redux'
+import I from 'immutable'
 
 import database from '../../../context/db'
 
@@ -9,19 +10,14 @@ import SongListComponent from './songListComponent'
 class SongList extends React.Component {
   constructor() {
     super();
-
-    this.state = {
-      tracks: []
-    };
   }
 
   getPlayList(props) {
     return new Promise((resolve, reject) => {
       database.open((db) => {
         db.all('SELECT * FROM playlist WHERE albumArtist = ? and album = ?',
-          [props.selected.artist, props.selected.album], (error, results) => {
+          [props.selected.get('artist'), props.selected.get('album')], (error, results) => {
             if (results) {
-              console.debug(results);
               resolve(results);
             } else {
               console.error(error);
@@ -36,29 +32,38 @@ class SongList extends React.Component {
 
   render() {
     return (<SongListComponent
-      trackList={this.state.tracks}
-      selectedFile={this.props.selected.file}
-      playingFile={this.props.playing.file}
+      trackList={this.props.library.get('tracks')}
+      selectedFile={this.props.selected.get('file')}
+      playingFile={this.props.playing.get('file')}
     />)
   }
 
   componentWillReceiveProps(nextProps) {
-    if (this.props.selected.artist !== nextProps.selected.artist ||
-        this.props.selected.album !== nextProps.selected.album) {
+    if ((this.props.selected.get('album') && this.props.selected.get('artist')) &&
+        this.props.selected.get('artist') !== nextProps.selected.get('artist') ||
+        this.props.selected.get('album') !== nextProps.selected.get('album')) {
       this.getPlayList(nextProps).then((data) => {
-        this.setState({
-          tracks: data
+        this.props.dispatch({
+          type: 'SET_LIBRARY_TRACKS',
+          value: data
         });
       });
     }
   }
 
+  shouldComponentUpdate(nextState) {
+    return !I.is(nextState.library.get('tracks'), this.props.library.get('tracks')) ||
+           nextState.selected.get('file') !== this.props.selected.get('file') ||
+           nextState.playing.get('file') !== this.props.playing.get('file');
+  }
+
 }
 
 const mapStatesToProps = (store) => {
   return {
-    selected: store.selected,
-    playing: store.playing
+    selected: store.get('selected'),
+    playing: store.get('playing'),
+    library: store.get('library')
   }
 };
 
diff --git a/src/context/Player.js b/src/context/Player.js
index 6f6b186..3e0cc09 100644
--- a/src/context/Player.js
+++ b/src/context/Player.js
@@ -36,7 +36,7 @@ class Player {
 
     if (!this.state.isPlaying) {
       if (!this.player || this.player.isStop) {
-        let track = file || store.playing.track || store.selected.track;
+        let track = file || store.getIn(['playing', 'file']) || store.getIn(['selected', 'file']);
 
         if (!track) {
           throw new Error('Select a file first!');
@@ -68,7 +68,7 @@ class Player {
   toggle() {
     let store = this.store.getState();
 
-    if (store.isPlaying) {
+    if (store.get('isPlaying')) {
       this.pause();
     } else {
       this.play();
diff --git a/src/reducers/index.js b/src/reducers/index.js
index 46bb45d..e8f5b80 100644
--- a/src/reducers/index.js
+++ b/src/reducers/index.js
@@ -1,4 +1,6 @@
-const initObject = {
+import Immutable from 'immutable';
+
+const initObject = Immutable.fromJS({
   isPlaying: false,
   libraryUpdated: false,
   playing: {
@@ -12,68 +14,60 @@ const initObject = {
     album: null,
     title: null,
     file: null
+  },
+  library: {
+    artists: [],
+    albums: [],
+    tracks: []
   }
-};
+});
 
 function mainReducer(state = initObject, action) {
   switch (action.type) {
     case 'PLAY':
-      return Object.assign({}, state, {
-        isPlaying: true,
-        playing: Object.assign({}, state.playing, {
-          file: action.value.file,
-          title: action.value.title
-        }),
-        selected: Object.assign({}, state.selected, {
-          file: action.value.file,
-          title: action.value.title
-        })
-      });
+    return state.set('isPlaying', true).
+      setIn(['playing', 'file'], action.value.file).
+      setIn(['playing', 'title'], action.value.title).
+      setIn(['selected', 'file'], action.value.file).
+      setIn(['selected', 'title'], action.value.title);
 
     case 'STOP':
-      return Object.assign({}, state, {
-        isPlaying: false
-      });
+      return state.set('isPlaying', false);
 
     case 'TOGGLE_PLAY':
-      return Object.assign({}, state, {
-        isPlaying: !state.isPlaying
-      });
+      return state.set('isPlaying', !state.get('isPlaying'));
 
     case 'SET_SELECTED_ARTIST':
-      return Object.assign({}, state, {
-        selected: Object.assign({}, state.selected, {
-          artist: action.value
-        })
-      });
+      return state.setIn(['selected', 'artist'], action.value);
 
     case 'SET_SELECTED_ALBUM':
-      return Object.assign({}, state, {
-        selected: Object.assign({}, state.selected, {
-          album: action.value
-        })
-      });
+      return state.setIn(['selected', 'album'], action.value);
 
     case 'SET_SELECTED_TRACK':
-      return Object.assign({}, state, {
-        selected: Object.assign({}, state.selected, {
-          title: action.value.title,
-          file: action.value.file
-        })
-      });
+      return state.setIn(['selected', 'title'], action.value.title).
+        setIn(['selected', 'file'], action.value.file);
 
     case 'SET_PLAYING_TRACK':
-      return Object.assign({}, state, {
-        playing: Object.assign({}, state.playing, {
-          title: action.value.title,
-          file: action.value.file
-        })
-      });
+      return state.setIn(['playing', 'title'], action.value.title).
+       setIn(['playing', 'file'], action.value.file);
 
     case 'LIBRARY_UPDATED':
-      return Object.assign({}, state, {
-        libraryUpdated: true
-      });
+      return state.set('libraryUpdated', true).
+        set('selected', Immutable.Map());
+
+    case 'LIBRARY_DID_UPDATE':
+      return state.set('libraryUpdated', false);
+
+    case 'SET_LIBRARY_ARTISTS':
+      return state.setIn(['library', 'artists'], Immutable.fromJS(action.value)).
+        setIn(['library', 'albums'], Immutable.List());
+
+    case 'SET_LIBRARY_ALBUMS':
+      return state.setIn(['library', 'albums'], Immutable.fromJS(action.value)).
+        setIn(['library', 'tracks'], Immutable.List());
+
+    case 'SET_LIBRARY_TRACKS':
+      return state.setIn(['library', 'tracks'], Immutable.fromJS(action.value));
 
     default:
       return state;