diff --git a/backend/Gemfile b/backend/Gemfile
index 90b9edf..a486b04 100644
--- a/backend/Gemfile
+++ b/backend/Gemfile
@@ -6,10 +6,10 @@ ruby "3.3.4"
 gem "rails", "~> 7.1.3", ">= 7.1.3.4"
 # [1.1] APIs
 # JSON APIs
-# gem "jbuilder"
+gem "jbuilder"
 
 # Use Rack CORS for handling Cross-Origin Resource Sharing (CORS), making cross-origin Ajax possible
-# gem "rack-cors"
+gem "rack-cors"
 
 
 # [2] Storage
@@ -79,5 +79,6 @@ group :development do
   # gem "spring"
   # Errors
   gem "better_errors", "~> 2.10"
+  # Models
+  gem "annotate", "~> 3.2"
 end
-
diff --git a/backend/Gemfile.lock b/backend/Gemfile.lock
index dc865c2..7f93977 100644
--- a/backend/Gemfile.lock
+++ b/backend/Gemfile.lock
@@ -75,6 +75,9 @@ GEM
       minitest (>= 5.1)
       mutex_m
       tzinfo (~> 2.0)
+    annotate (3.2.0)
+      activerecord (>= 3.2, < 8.0)
+      rake (>= 10.4, < 14.0)
     base64 (0.2.0)
     better_errors (2.10.1)
       erubi (>= 1.0.0)
@@ -138,6 +141,9 @@ GEM
     irb (1.14.0)
       rdoc (>= 4.0.0)
       reline (>= 0.4.2)
+    jbuilder (2.12.0)
+      actionview (>= 5.0.0)
+      activesupport (>= 5.0.0)
     listen (3.9.0)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
@@ -194,6 +200,8 @@ GEM
       nio4r (~> 2.0)
     racc (1.8.1)
     rack (3.1.7)
+    rack-cors (2.0.2)
+      rack (>= 2.0.0)
     rack-session (2.0.0)
       rack (>= 3.0.0)
     rack-test (2.1.0)
@@ -289,6 +297,7 @@ PLATFORMS
   x86_64-linux
 
 DEPENDENCIES
+  annotate (~> 3.2)
   better_errors (~> 2.10)
   bootsnap
   database_cleaner (~> 2.0)
@@ -298,9 +307,11 @@ DEPENDENCIES
   faker (~> 3.4)
   guard (~> 2.18)
   guard-rspec (~> 4.7)
+  jbuilder
   pg (~> 1.1)
   pry-rails (~> 0.3.11)
   puma (>= 5.0)
+  rack-cors
   rails (~> 7.1.3, >= 7.1.3.4)
   rspec-rails (~> 6.1)
   shoulda-matchers (~> 6.2)
diff --git a/backend/config/initializers/cors.rb b/backend/config/initializers/cors.rb
index 0c5dd99..e81c04c 100644
--- a/backend/config/initializers/cors.rb
+++ b/backend/config/initializers/cors.rb
@@ -5,12 +5,14 @@
 
 # Read more: https://github.com/cyu/rack-cors
 
-# Rails.application.config.middleware.insert_before 0, Rack::Cors do
-#   allow do
-#     origins "example.com"
-#
-#     resource "*",
-#       headers: :any,
-#       methods: [:get, :post, :put, :patch, :delete, :options, :head]
-#   end
-# end
+Rails.application.config.middleware.insert_before 0, Rack::Cors do
+  allow do
+    origins "*"
+    # origins "http://vue:8080"
+
+    resource "*",
+      headers: :any,
+      # credentials: true,
+      methods: [:get, :post, :put, :patch, :delete, :options, :head]
+  end
+end