diff --git a/app/controllers/api/application_controller.rb b/app/controllers/api/application_controller.rb
index 60e876d..d8a77e7 100644
--- a/app/controllers/api/application_controller.rb
+++ b/app/controllers/api/application_controller.rb
@@ -1,7 +1,7 @@
 module API
   class ApplicationController < ::ApplicationController
     skip_before_filter :verify_authenticity_token
-    skip_before_filter :authenticate!, only: [:cor_preflight]
+    skip_before_filter :authenticate!, only: :cor_preflight
 
     before_filter :cor_filter
 
diff --git a/app/controllers/api/playlists_controller.rb b/app/controllers/api/playlists_controller.rb
index 8f83019..b3a576a 100644
--- a/app/controllers/api/playlists_controller.rb
+++ b/app/controllers/api/playlists_controller.rb
@@ -5,14 +5,15 @@ module API
     end
 
     def create
-      @playlist = current_user.playlists.build(playlist_params)
+      @playlist = current_user.playlists.build playlist_params
       @playlist.save
     end
 
+
     private
 
     def playlist_params
-      params.require(:playlist).permit(:name)
+      params.require(:playlist).permit :name
     end
   end
 end
diff --git a/app/controllers/api/sessions_controller.rb b/app/controllers/api/sessions_controller.rb
index eaad78a..2877932 100644
--- a/app/controllers/api/sessions_controller.rb
+++ b/app/controllers/api/sessions_controller.rb
@@ -1,11 +1,11 @@
 module API
   class SessionsController < ApplicationController
-    skip_before_filter :authenticate!, only: [:create]
+    skip_before_filter :authenticate!, only: :create
 
     def create
       user = User.find_by_email(params[:session][:email])
 
-      unless user.try(:authenticate?, params[:session][:password])
+      unless user.try :authenticate?, params[:session][:password]
         return render json: '', status: :not_found
       end
 
diff --git a/app/controllers/api/sounds_controller.rb b/app/controllers/api/sounds_controller.rb
index b5f3321..b7b9178 100644
--- a/app/controllers/api/sounds_controller.rb
+++ b/app/controllers/api/sounds_controller.rb
@@ -2,7 +2,7 @@ module API
   class SoundsController < ApplicationController
     # FIXME: add some tests!
     def show
-      sound = Sound.find params[:id]
+      sound = Sound.find(params[:id])
       send_file sound.path, type: sound.mime_type
     end
   end
diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index 5b08613..ae6546f 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -3,7 +3,7 @@ class ApplicationController < ActionController::Base
 
   before_filter :authenticate!
 
-  def current_user=(user)
+  def current_user= user
     session[:user_id] = user.id
   end
 
@@ -11,6 +11,7 @@ class ApplicationController < ActionController::Base
     @current_user ||= User.find(session[:user_id]) if session[:user_id]
   end
 
+
   protected
 
   def authenticate!
diff --git a/app/controllers/home_controller.rb b/app/controllers/home_controller.rb
index 872e743..e8ea6df 100644
--- a/app/controllers/home_controller.rb
+++ b/app/controllers/home_controller.rb
@@ -1,6 +1,6 @@
 class HomeController < ApplicationController
   def index
-    @playlists = Playlist.all
-    @tracks = Track.latest
+    @playlists  = Playlist.all
+    @tracks     = Track.latest
   end
 end
diff --git a/app/controllers/playlists_controller.rb b/app/controllers/playlists_controller.rb
index ef39ded..9fdcc36 100644
--- a/app/controllers/playlists_controller.rb
+++ b/app/controllers/playlists_controller.rb
@@ -8,7 +8,8 @@ class PlaylistsController < ApplicationController
   end
 
   def create
-    @playlist = current_user.playlists.build(playlist_params)
+    @playlist = current_user.playlists.build playlist_params
+
     if @playlist.save
       redirect_to action: 'index'
     else
@@ -22,6 +23,7 @@ class PlaylistsController < ApplicationController
 
   def update
     @playlist = Playlist.find(params[:id])
+
     if @playlist.update_attributes playlist_params
       redirect_to action: 'index'
     else
@@ -29,9 +31,10 @@ class PlaylistsController < ApplicationController
     end
   end
 
+
   private
 
   def playlist_params
-    params.require(:playlist).permit(:name)
+    params.require(:playlist).permit :name
   end
 end
diff --git a/app/controllers/sessions_controller.rb b/app/controllers/sessions_controller.rb
index ba207cb..ccc72d5 100644
--- a/app/controllers/sessions_controller.rb
+++ b/app/controllers/sessions_controller.rb
@@ -1,9 +1,10 @@
 class SessionsController < ApplicationController
-  skip_before_filter :authenticate!, only: [:new, :create]
+  skip_before_filter :authenticate!, only: %i[new create]
 
   def create
     user = User.find_by_email(params[:session][:email])
-    if user.try(:authenticate?, params[:session][:password])
+
+    if user.try :authenticate?, params[:session][:password]
       self.current_user = user
       redirect_to :root
     else
diff --git a/app/controllers/sounds_controller.rb b/app/controllers/sounds_controller.rb
index c047256..5a9b70d 100644
--- a/app/controllers/sounds_controller.rb
+++ b/app/controllers/sounds_controller.rb
@@ -1,6 +1,6 @@
 class SoundsController < ApplicationController
   def show
-    sound = Sound.find params[:id]
+    sound = Sound.find(params[:id])
     send_file sound.path, type: sound.mime_type
   end
 end
diff --git a/app/controllers/tracks_controller.rb b/app/controllers/tracks_controller.rb
index b9b3b4e..a53ac74 100644
--- a/app/controllers/tracks_controller.rb
+++ b/app/controllers/tracks_controller.rb
@@ -1,6 +1,6 @@
 class TracksController < ApplicationController
   def show
-    @track = Track.find params[:id]
+    @track = Track.find(params[:id])
   end
 
   def new
@@ -8,7 +8,8 @@ class TracksController < ApplicationController
   end
 
   def create
-    @track = Track.new track_params
+    @track = Track.new(track_params)
+
     if @track.save
       redirect_to @track
     else
@@ -19,6 +20,6 @@ class TracksController < ApplicationController
   private
 
   def track_params
-    params.require(:track).permit(:name, :file)
+    params.require(:track).permit %i[name file]
   end
 end
diff --git a/app/controllers/users_controller.rb b/app/controllers/users_controller.rb
index ce251ce..ed0d0b5 100644
--- a/app/controllers/users_controller.rb
+++ b/app/controllers/users_controller.rb
@@ -1,5 +1,5 @@
 class UsersController < ApplicationController
-  skip_before_filter :authenticate!, only: [:new, :create]
+  skip_before_filter :authenticate!, only: %i[new create]
 
   def new
     @user = User.new
@@ -7,6 +7,7 @@ class UsersController < ApplicationController
 
   def create
     @user = User.new(user_params)
+
     if !@user.save
       render :new
     else
@@ -18,6 +19,6 @@ class UsersController < ApplicationController
   private
 
   def user_params
-    params.require(:user).permit(:email, :password, :password_confirmation)
+    params.require(:user).permit %i[email password password_confirmation]
   end
 end
diff --git a/app/models/sound.rb b/app/models/sound.rb
index 6dfd0d6..7ddfec6 100644
--- a/app/models/sound.rb
+++ b/app/models/sound.rb
@@ -10,7 +10,7 @@ class Sound < ActiveRecord::Base
     "#{Rails.configuration.sounds_path}/#{sha256}"
   end
 
-  def file=(file)
+  def file= file
     self.sha256 = Digest::SHA256.file(file.path).hexdigest
     FileUtils.cp file.path, path
     self.mime_type = file.content_type
diff --git a/app/models/track.rb b/app/models/track.rb
index 46c81dd..2fb9274 100644
--- a/app/models/track.rb
+++ b/app/models/track.rb
@@ -3,8 +3,8 @@ class Track < ActiveRecord::Base
 
   validates_presence_of :name
 
-  def file=(file)
-    sounds.build(file: file)
+  def file= file
+    sounds.build file: file
   end
 
   def sound
diff --git a/app/models/user.rb b/app/models/user.rb
index 81b8ad2..1b6a416 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -15,12 +15,12 @@ class User < ActiveRecord::Base
     confirmation: true
   validates_presence_of :password_hash
 
-  def password=(plain_password)
+  def password= plain_password
     @password = plain_password
     self.password_hash = Password.create(plain_password)
   end
 
-  def authenticate?(password)
+  def authenticate? password
     Password.new(password_hash) == password
   end
 end
diff --git a/app/views/sessions/new.html.haml b/app/views/sessions/new.html.haml
index fbffef9..5e994e3 100644
--- a/app/views/sessions/new.html.haml
+++ b/app/views/sessions/new.html.haml
@@ -1,4 +1,4 @@
-= form_for(:session, url: sessions_path) do |f|
+= form_for :session, url: sessions_path do |f|
   %table
     %tbody
       %tr
diff --git a/app/views/users/new.html.haml b/app/views/users/new.html.haml
index 0280580..4ac7f44 100644
--- a/app/views/users/new.html.haml
+++ b/app/views/users/new.html.haml
@@ -1,4 +1,4 @@
-= form_for(@user, url: users_path) do |f|
+= form_for @user, url: users_path do |f|
   - if @user.errors.any?
     %ul
       - @user.errors.full_messages.each do |m|