diff --git a/Gemfile b/Gemfile
index 7e799e0..682495d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,8 +2,6 @@ source 'https://rubygems.org'
 
 # Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
 gem 'rails', '4.2.5'
-# Use sqlite3 as the database for Active Record
-gem 'sqlite3'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5.0'
 # Use Uglifier as compressor for JavaScript assets
@@ -32,6 +30,10 @@ gem 'bcrypt', '~> 3.1.7'
 # gem 'capistrano-rails', group: :development
 
 group :development, :test do
+  
+  # Use sqlite3 as the database for Active Record
+  gem 'sqlite3'
+  
   # Call 'byebug' anywhere in the code to stop execution and get a debugger console
   gem 'byebug'
   
@@ -47,6 +49,7 @@ group :development, :test do
 end
 
 group :development do
+  
   # Access an IRB console on exception pages or by using <%= console %> in views
   gem 'web-console', '~> 2.0'
 
@@ -66,3 +69,8 @@ group :test do
   #结合 Capybara 测试基于 JavaScript 的交互操作
   gem 'selenium-webdriver'
 end
+
+group :production do
+  gem 'pg' # for Heroku deployment
+  gem 'rails_12factor'
+end
\ No newline at end of file
diff --git a/Gemfile.lock b/Gemfile.lock
index 2d803db..1b075a1 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -42,7 +42,7 @@ GEM
       memoizable (~> 0.4.0)
     addressable (2.5.0)
       public_suffix (~> 2.0, >= 2.0.2)
-    arel (6.0.3)
+    arel (6.0.4)
     arrayfields (4.9.2)
     ast (2.3.0)
     bcrypt (3.1.11)
@@ -84,7 +84,7 @@ GEM
     concord (0.1.5)
       adamantium (~> 0.2.0)
       equalizer (~> 0.0.9)
-    concurrent-ruby (1.0.3)
+    concurrent-ruby (1.0.4)
     database_cleaner (1.5.3)
     debug_inspector (0.0.2)
     diff-lcs (1.2.5)
@@ -99,7 +99,7 @@ GEM
     factory_girl_rails (4.7.0)
       factory_girl (~> 4.7.0)
       railties (>= 3.0.0)
-    faker (1.7.0)
+    faker (1.7.1)
       i18n (~> 0.5)
     fattr (2.3.0)
     ffi (1.9.14)
@@ -122,7 +122,7 @@ GEM
     jbuilder (2.6.1)
       activesupport (>= 3.0.0, < 5.1)
       multi_json (~> 1.2)
-    jquery-rails (4.2.1)
+    jquery-rails (4.2.2)
       rails-dom-testing (>= 1, < 3)
       railties (>= 4.2.0)
       thor (>= 0.14, < 2.0)
@@ -165,14 +165,15 @@ GEM
     minitest (5.10.1)
     multi_json (1.12.1)
     netrc (0.11.0)
-    nokogiri (1.6.8.1)
+    nokogiri (1.7.0)
       mini_portile2 (~> 2.1.0)
     parallel (1.10.0)
     parser (2.3.3.1)
       ast (~> 2.2)
     path_expander (1.0.1)
+    pg (0.19.0)
     procto (0.0.3)
-    public_suffix (2.0.4)
+    public_suffix (2.0.5)
     rack (1.6.5)
     rack-test (0.6.3)
       rack (>= 1.0)
@@ -189,12 +190,15 @@ GEM
       sprockets-rails
     rails-deprecated_sanitizer (1.0.3)
       activesupport (>= 4.2.0.alpha)
-    rails-dom-testing (1.0.7)
+    rails-dom-testing (1.0.8)
       activesupport (>= 4.2.0.beta, < 5.0)
-      nokogiri (~> 1.6.0)
+      nokogiri (~> 1.6)
       rails-deprecated_sanitizer (>= 1.0.1)
     rails-html-sanitizer (1.0.3)
       loofah (~> 2.0)
+    rails_12factor (0.0.3)
+      rails_serve_static_assets
+      rails_stdout_logging
     rails_best_practices (1.17.0)
       activesupport
       code_analyzer (>= 0.4.3)
@@ -203,12 +207,14 @@ GEM
       json
       require_all
       ruby-progressbar
+    rails_serve_static_assets (0.0.5)
+    rails_stdout_logging (0.0.5)
     railties (4.2.5)
       actionpack (= 4.2.5)
       activesupport (= 4.2.5)
       rake (>= 0.8.7)
       thor (>= 0.18.1, < 2.0)
-    rainbow (2.1.0)
+    rainbow (2.2.1)
     rake (12.0.0)
     rdoc (4.3.0)
     redcard (1.1.0)
@@ -255,7 +261,7 @@ GEM
     sdoc (0.4.2)
       json (~> 1.7, >= 1.7.7)
       rdoc (~> 4.0)
-    selenium-webdriver (3.0.4)
+    selenium-webdriver (3.0.5)
       childprocess (~> 0.5)
       rubyzip (~> 1.0)
       websocket (~> 1.0)
@@ -324,7 +330,9 @@ DEPENDENCIES
   jquery-rails
   launchy
   metric_fu
+  pg
   rails (= 4.2.5)
+  rails_12factor
   rspec-rails (~> 3.5.2)
   sass-rails (~> 5.0)
   sdoc (~> 0.4.0)