diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 42abc49..4d67027 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -7,16 +7,31 @@ on:
       - main
 
 jobs:
-  build:
-    runs-on: ubuntu-latest
+  RSpec:
+    runs-on: ubuntu-24.04
+    strategy:
+      matrix:
+        ruby: [ '2.7', '3.0', '3.1', '3.2', '3.3', '3.4' ]
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
-        ruby-version: 2.6
-    - name: Run the default task
+        ruby-version: ${{ matrix.ruby }}
+    - name: Build
       run: |
-        gem install bundler -v 2.2.3
         bundle install
-        bundle exec rake
+        bundle exec rspec
+
+  Rubocop:
+    runs-on: ubuntu-24.04
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: '3.4'
+          bundler-cache: true
+      - name: Rubocop
+        run: | 
+          bundle install
+          bundle exec rubocop
diff --git a/.rubocop.yml b/.rubocop.yml
index 3b0925d..ff2593d 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,4 +1,4 @@
-require:
+plugins:
   - rubocop-rspec
 
 AllCops:
diff --git a/Gemfile b/Gemfile
index 7d35961..3cbd059 100644
--- a/Gemfile
+++ b/Gemfile
@@ -5,9 +5,14 @@ source 'https://rubygems.org'
 # Specify your gem's dependencies in gravity_mailbox.gemspec
 gemspec
 
+gem 'base64'
+gem 'bigdecimal'
 gem 'combustion'
+gem 'drb'
+gem 'mutex_m'
+gem 'net-http'
 gem 'rails-controller-testing'
-gem 'rake', '~> 13.0'
+gem 'rake'
 gem 'rspec'
 gem 'rspec-rails'
 gem 'rubocop'
diff --git a/Gemfile.lock b/Gemfile.lock
index e00e2c8..aaf5d7d 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -2,218 +2,187 @@ PATH
   remote: .
   specs:
     gravity_mailbox (0.4.1)
-      rails (>= 6.0)
+      actionmailer (>= 7.0)
+      railties (>= 7.0)
 
 GEM
   remote: https://rubygems.org/
   specs:
-    actioncable (6.1.7.3)
-      actionpack (= 6.1.7.3)
-      activesupport (= 6.1.7.3)
-      nio4r (~> 2.0)
-      websocket-driver (>= 0.6.1)
-    actionmailbox (6.1.7.3)
-      actionpack (= 6.1.7.3)
-      activejob (= 6.1.7.3)
-      activerecord (= 6.1.7.3)
-      activestorage (= 6.1.7.3)
-      activesupport (= 6.1.7.3)
-      mail (>= 2.7.1)
-    actionmailer (6.1.7.3)
-      actionpack (= 6.1.7.3)
-      actionview (= 6.1.7.3)
-      activejob (= 6.1.7.3)
-      activesupport (= 6.1.7.3)
+    actionmailer (7.0.8.7)
+      actionpack (= 7.0.8.7)
+      actionview (= 7.0.8.7)
+      activejob (= 7.0.8.7)
+      activesupport (= 7.0.8.7)
       mail (~> 2.5, >= 2.5.4)
+      net-imap
+      net-pop
+      net-smtp
       rails-dom-testing (~> 2.0)
-    actionpack (6.1.7.3)
-      actionview (= 6.1.7.3)
-      activesupport (= 6.1.7.3)
-      rack (~> 2.0, >= 2.0.9)
+    actionpack (7.0.8.7)
+      actionview (= 7.0.8.7)
+      activesupport (= 7.0.8.7)
+      rack (~> 2.0, >= 2.2.4)
       rack-test (>= 0.6.3)
       rails-dom-testing (~> 2.0)
       rails-html-sanitizer (~> 1.0, >= 1.2.0)
-    actiontext (6.1.7.3)
-      actionpack (= 6.1.7.3)
-      activerecord (= 6.1.7.3)
-      activestorage (= 6.1.7.3)
-      activesupport (= 6.1.7.3)
-      nokogiri (>= 1.8.5)
-    actionview (6.1.7.3)
-      activesupport (= 6.1.7.3)
+    actionview (7.0.8.7)
+      activesupport (= 7.0.8.7)
       builder (~> 3.1)
       erubi (~> 1.4)
       rails-dom-testing (~> 2.0)
       rails-html-sanitizer (~> 1.1, >= 1.2.0)
-    activejob (6.1.7.3)
-      activesupport (= 6.1.7.3)
+    activejob (7.0.8.7)
+      activesupport (= 7.0.8.7)
       globalid (>= 0.3.6)
-    activemodel (6.1.7.3)
-      activesupport (= 6.1.7.3)
-    activerecord (6.1.7.3)
-      activemodel (= 6.1.7.3)
-      activesupport (= 6.1.7.3)
-    activestorage (6.1.7.3)
-      actionpack (= 6.1.7.3)
-      activejob (= 6.1.7.3)
-      activerecord (= 6.1.7.3)
-      activesupport (= 6.1.7.3)
-      marcel (~> 1.0)
-      mini_mime (>= 1.1.0)
-    activesupport (6.1.7.3)
+    activesupport (7.0.8.7)
       concurrent-ruby (~> 1.0, >= 1.0.2)
       i18n (>= 1.6, < 2)
       minitest (>= 5.1)
       tzinfo (~> 2.0)
-      zeitwerk (~> 2.3)
-    ast (2.4.2)
-    builder (3.2.4)
-    combustion (1.3.7)
+    ast (2.4.3)
+    base64 (0.3.0)
+    bigdecimal (3.2.2)
+    builder (3.3.0)
+    combustion (1.5.0)
       activesupport (>= 3.0.0)
       railties (>= 3.0.0)
       thor (>= 0.14.6)
-    concurrent-ruby (1.1.10)
+    concurrent-ruby (1.3.4)
     crass (1.0.6)
-    date (3.3.3)
-    diff-lcs (1.5.0)
-    erubi (1.12.0)
-    globalid (1.1.0)
-      activesupport (>= 5.0)
-    i18n (1.12.0)
+    date (3.4.1)
+    diff-lcs (1.6.2)
+    drb (2.2.3)
+    erubi (1.13.1)
+    globalid (1.2.1)
+      activesupport (>= 6.1)
+    i18n (1.14.7)
       concurrent-ruby (~> 1.0)
-    json (2.6.2)
-    loofah (2.19.1)
+    json (2.13.2)
+    language_server-protocol (3.17.0.5)
+    lint_roller (1.1.0)
+    loofah (2.24.1)
       crass (~> 1.0.2)
-      nokogiri (>= 1.5.9)
+      nokogiri (>= 1.12.0)
     mail (2.8.1)
       mini_mime (>= 0.1.1)
       net-imap
       net-pop
       net-smtp
-    marcel (1.0.2)
-    method_source (1.0.0)
-    mini_mime (1.1.2)
-    mini_portile2 (2.8.2)
-    minitest (5.17.0)
-    net-imap (0.3.6)
+    method_source (1.1.0)
+    mini_mime (1.1.5)
+    mini_portile2 (2.8.9)
+    minitest (5.25.5)
+    mutex_m (0.3.0)
+    net-http (0.2.2)
+      uri
+    net-imap (0.4.22)
       date
       net-protocol
     net-pop (0.1.2)
       net-protocol
-    net-protocol (0.2.1)
+    net-protocol (0.2.2)
       timeout
-    net-smtp (0.3.3)
+    net-smtp (0.5.1)
       net-protocol
-    nio4r (2.5.9)
-    nokogiri (1.13.10)
-      mini_portile2 (~> 2.8.0)
+    nokogiri (1.15.7)
+      mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
-    parallel (1.22.1)
-    parser (3.1.2.1)
+    parallel (1.27.0)
+    parser (3.3.9.0)
       ast (~> 2.4.1)
-    racc (1.7.1)
-    rack (2.2.7)
-    rack-test (2.0.2)
+      racc
+    prism (1.4.0)
+    racc (1.8.1)
+    rack (2.2.17)
+    rack-test (2.2.0)
       rack (>= 1.3)
-    rails (6.1.7.3)
-      actioncable (= 6.1.7.3)
-      actionmailbox (= 6.1.7.3)
-      actionmailer (= 6.1.7.3)
-      actionpack (= 6.1.7.3)
-      actiontext (= 6.1.7.3)
-      actionview (= 6.1.7.3)
-      activejob (= 6.1.7.3)
-      activemodel (= 6.1.7.3)
-      activerecord (= 6.1.7.3)
-      activestorage (= 6.1.7.3)
-      activesupport (= 6.1.7.3)
-      bundler (>= 1.15.0)
-      railties (= 6.1.7.3)
-      sprockets-rails (>= 2.0.0)
     rails-controller-testing (1.0.5)
       actionpack (>= 5.0.1.rc1)
       actionview (>= 5.0.1.rc1)
       activesupport (>= 5.0.1.rc1)
-    rails-dom-testing (2.0.3)
-      activesupport (>= 4.2.0)
+    rails-dom-testing (2.3.0)
+      activesupport (>= 5.0.0)
+      minitest
       nokogiri (>= 1.6)
-    rails-html-sanitizer (1.5.0)
-      loofah (~> 2.19, >= 2.19.1)
-    railties (6.1.7.3)
-      actionpack (= 6.1.7.3)
-      activesupport (= 6.1.7.3)
+    rails-html-sanitizer (1.6.2)
+      loofah (~> 2.21)
+      nokogiri (>= 1.15.7, != 1.16.7, != 1.16.6, != 1.16.5, != 1.16.4, != 1.16.3, != 1.16.2, != 1.16.1, != 1.16.0.rc1, != 1.16.0)
+    railties (7.0.8.7)
+      actionpack (= 7.0.8.7)
+      activesupport (= 7.0.8.7)
       method_source
       rake (>= 12.2)
       thor (~> 1.0)
+      zeitwerk (~> 2.5)
     rainbow (3.1.1)
-    rake (13.0.6)
-    regexp_parser (2.6.0)
-    rexml (3.2.5)
-    rspec (3.12.0)
-      rspec-core (~> 3.12.0)
-      rspec-expectations (~> 3.12.0)
-      rspec-mocks (~> 3.12.0)
-    rspec-core (3.12.0)
-      rspec-support (~> 3.12.0)
-    rspec-expectations (3.12.0)
+    rake (13.3.0)
+    regexp_parser (2.11.2)
+    rspec (3.13.1)
+      rspec-core (~> 3.13.0)
+      rspec-expectations (~> 3.13.0)
+      rspec-mocks (~> 3.13.0)
+    rspec-core (3.13.5)
+      rspec-support (~> 3.13.0)
+    rspec-expectations (3.13.5)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.12.0)
-    rspec-mocks (3.12.0)
+      rspec-support (~> 3.13.0)
+    rspec-mocks (3.13.5)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.12.0)
-    rspec-rails (5.1.2)
-      actionpack (>= 5.2)
-      activesupport (>= 5.2)
-      railties (>= 5.2)
-      rspec-core (~> 3.10)
-      rspec-expectations (~> 3.10)
-      rspec-mocks (~> 3.10)
-      rspec-support (~> 3.10)
-    rspec-support (3.12.0)
-    rubocop (1.38.0)
+      rspec-support (~> 3.13.0)
+    rspec-rails (7.1.1)
+      actionpack (>= 7.0)
+      activesupport (>= 7.0)
+      railties (>= 7.0)
+      rspec-core (~> 3.13)
+      rspec-expectations (~> 3.13)
+      rspec-mocks (~> 3.13)
+      rspec-support (~> 3.13)
+    rspec-support (3.13.5)
+    rubocop (1.79.2)
       json (~> 2.3)
+      language_server-protocol (~> 3.17.0.2)
+      lint_roller (~> 1.1.0)
       parallel (~> 1.10)
-      parser (>= 3.1.2.1)
+      parser (>= 3.3.0.2)
       rainbow (>= 2.2.2, < 4.0)
-      regexp_parser (>= 1.8, < 3.0)
-      rexml (>= 3.2.5, < 4.0)
-      rubocop-ast (>= 1.23.0, < 2.0)
+      regexp_parser (>= 2.9.3, < 3.0)
+      rubocop-ast (>= 1.46.0, < 2.0)
       ruby-progressbar (~> 1.7)
-      unicode-display_width (>= 1.4.0, < 3.0)
-    rubocop-ast (1.23.0)
-      parser (>= 3.1.1.0)
-    rubocop-rspec (2.17.1)
-      rubocop (~> 1.33)
-    ruby-progressbar (1.11.0)
-    sprockets (4.2.0)
-      concurrent-ruby (~> 1.0)
-      rack (>= 2.2.4, < 4)
-    sprockets-rails (3.4.2)
-      actionpack (>= 5.2)
-      activesupport (>= 5.2)
-      sprockets (>= 3.0.0)
-    thor (1.2.2)
-    timeout (0.3.2)
+      unicode-display_width (>= 2.4.0, < 4.0)
+    rubocop-ast (1.46.0)
+      parser (>= 3.3.7.2)
+      prism (~> 1.4)
+    rubocop-rspec (3.6.0)
+      lint_roller (~> 1.1)
+      rubocop (~> 1.72, >= 1.72.1)
+    ruby-progressbar (1.13.0)
+    thor (1.4.0)
+    timeout (0.4.3)
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
-    unicode-display_width (2.3.0)
-    websocket-driver (0.7.5)
-      websocket-extensions (>= 0.1.0)
-    websocket-extensions (0.1.5)
-    zeitwerk (2.6.8)
+    unicode-display_width (3.1.5)
+      unicode-emoji (~> 4.0, >= 4.0.4)
+    unicode-emoji (4.0.4)
+    uri (1.0.3)
+    zeitwerk (2.6.18)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
+  base64
+  bigdecimal
   combustion
+  drb
   gravity_mailbox!
+  mutex_m
+  net-http
   rails-controller-testing
-  rake (~> 13.0)
+  rake
   rspec
   rspec-rails
   rubocop
   rubocop-rspec
 
 BUNDLED WITH
-   2.2.3
+   2.4.22
diff --git a/gravity_mailbox.gemspec b/gravity_mailbox.gemspec
index 1d137a2..1038beb 100644
--- a/gravity_mailbox.gemspec
+++ b/gravity_mailbox.gemspec
@@ -13,7 +13,7 @@ Gem::Specification.new do |spec|
                        'sent by your Rails app directly through your Rails app.'
   spec.homepage      = 'https://github.com/petalmd/gravity_mailbox'
   spec.license       = 'MIT'
-  spec.required_ruby_version = Gem::Requirement.new('>= 2.6.0')
+  spec.required_ruby_version = Gem::Requirement.new('>= 2.7.0')
 
   spec.files = Dir['LICENSE.txt', 'README.md', 'lib/**/*', 'config/**/*', 'app/**/*']
   spec.extra_rdoc_files = %w[LICENSE.txt README.md]
@@ -27,5 +27,6 @@ Gem::Specification.new do |spec|
     'rubygems_mfa_required' => 'true'
   }
 
-  spec.add_dependency 'rails', '>= 6.0'
+  spec.add_dependency 'actionmailer', '>= 7.0'
+  spec.add_dependency 'railties', '>= 7.0'
 end
diff --git a/spec/controllers/gravity_mailbox/mailbox_controller_spec.rb b/spec/controllers/gravity_mailbox/mailbox_controller_spec.rb
index c9db3c5..330987d 100644
--- a/spec/controllers/gravity_mailbox/mailbox_controller_spec.rb
+++ b/spec/controllers/gravity_mailbox/mailbox_controller_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-RSpec.describe GravityMailbox::MailboxController, type: :controller do # rubocop:disable RSpec/Rails/InferredSpecType
+RSpec.describe GravityMailbox::MailboxController, type: :controller do
   before do
     @routes = GravityMailbox::Engine.routes
   end