diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 76833c9..c63941f 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -9,31 +9,32 @@ jobs:
     strategy:
       matrix:
         include:
-          - ruby_version: '2.7'
-            gemfile: rails_7_0
+          - ruby_version: '3.3'
+            gemfile: rails_7_1
             upload_coverage: true
-          - ruby_version: '2.5'
+          - ruby_version: '3.2'
+            gemfile: rails_7_1
+          # - ruby_version: '3.1'
+          #   gemfile: rails_7_1
+          - ruby_version: '3.3'
+            gemfile: rails_7_0
+          - ruby_version: '3.3'
             gemfile: rails_6_1
-          - ruby_version: '2.3'
-            gemfile: rails_5_0
-          - ruby_version: '2.3'
-            gemfile: rails_4_2
-            bundler: '1'
     env:
       CC_TEST_REPORTER_ID: ${{ secrets.CC_TEST_REPORTER_ID }}
-      CI: 1
       BUNDLE_GEMFILE: ${{ github.workspace }}/spec/gemfiles/${{ matrix.gemfile }}.gemfile
     steps:
       - name: "Determine whether to upload coverage"
         if: ${{ env.CC_TEST_REPORTER_ID && matrix.upload_coverage }}
         run: echo COVERAGE=1 >> $GITHUB_ENV
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up Ruby ${{ matrix.ruby_version }} and ${{ matrix.gemfile }}.gemfile
         uses: ruby/setup-ruby@v1
         with:
           ruby-version: ${{ matrix.ruby_version }}
           bundler: ${{ matrix.bundler || 'Gemfile.lock' }}
           bundler-cache: true
+          cache-version: 1000
       - name: Run tests
         if: ${{ !env.COVERAGE }}
         run: bundle exec rspec --format d
@@ -47,11 +48,11 @@ jobs:
     env:
       BUNDLE_GEMFILE: ${{ github.workspace }}/spec/gemfiles/i18n-tasks.gemfile
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up Ruby and i18n-tasks.gemfile
         uses: ruby/setup-ruby@v1
         with:
-          ruby-version: 3.2
+          ruby-version: 3.3
           bundler-cache: true
       - name: Run i18n-tasks
         run: bundle exec i18n-tasks health
diff --git a/CHANGES.md b/CHANGES.md
index 639b35c..1b6db33 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,7 @@
+* Remove explicit dependency on `sassc-rails`. Allow the use of this gem with either:
+  `dartsass-sprockets`, `sassc-rails`, `dartsass-rails`, or `cssbundling-rails`
+* Drop support for EOL ruby and rails versions (rails >6.1, ruby >3.1)
+
 ## v2.2.3
 
 * Fixes Rails 7 compatibility.
diff --git a/README.md b/README.md
index a525880..15b8bf7 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # Rails Email Preview [![Build Status][badge-ci]][ci] [![Test Coverage][coverage-badge]][coverage] [![Code Climate][codeclimate-badge]][codeclimate] [![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/glebm/rails_email_preview?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 
-Preview email in the browser with this Rails engine. Compatible with Rails 4.2+.
+Preview email in the browser with this Rails engine. Compatible with Rails 6.1+.
 
 An email review:
 
@@ -20,6 +20,12 @@ Add [![Gem Version][gem-badge]][gem] to Gemfile:
 gem 'rails_email_preview', '~> 2.2.3'
 ```
 
+This gem requires a Sass engine, please ensure you have **one** of these gems in your Gemfile:
+- [`dartsass-sprockets`](https://github.com/tablecheck/dartsass-sprockets): Dart Sass engine, recommended but only works for Ruby 2.6+ and Rails 5+
+- [`dartsass-rails`](https://github.com/rails/dartsass-rails): Dart Sass engine, recommended for Rails projects that use Propshaft
+- [`cssbundling-rails`](https://github.com/rails/cssbundling-rails): External Sass engine
+- [`sassc-rails`](https://github.com/sass/sassc-rails): SassC engine, deprecated but compatible with Ruby 2.3+ and Rails 4
+
 Add an initializer and the routes:
 
 ```console
diff --git a/lib/rails_email_preview.rb b/lib/rails_email_preview.rb
index 5b01444..599bf78 100644
--- a/lib/rails_email_preview.rb
+++ b/lib/rails_email_preview.rb
@@ -5,7 +5,25 @@
 require 'rails_email_preview/delivery_handler'
 require 'rails_email_preview/view_hooks'
 
-require 'sassc-rails'
+# sass engine loader
+begin
+  require 'dartsass-sprockets'
+rescue LoadError
+  begin
+    require 'sassc-rails'
+  rescue LoadError
+    begin
+      require 'dartsass-rails'
+    rescue LoadError
+      begin
+        require 'cssbundling-rails'
+      rescue LoadError
+        raise LoadError.new("rails_email_preview requires a Sass engine. Please add dartsass-sprockets, sassc-rails, dartsass-rails or cssbundling-rails to your dependencies.")
+      end
+    end
+  end
+end
+
 require 'request_store'
 require 'turbolinks'
 require 'pathname'
diff --git a/rails_email_preview.gemspec b/rails_email_preview.gemspec
index 807058b..43bb282 100644
--- a/rails_email_preview.gemspec
+++ b/rails_email_preview.gemspec
@@ -17,8 +17,7 @@ Gem::Specification.new do |s|
     s.metadata = { 'issue_tracker' => 'https://github.com/glebm/rails_email_preview' }
   end
 
-  s.add_dependency 'rails', '>= 4.2'
-  s.add_dependency 'sassc-rails', '>= 2.0.0'
+  s.add_dependency 'rails', '>= 6.1'
   s.add_dependency 'turbolinks'
   s.add_dependency 'request_store'
 
diff --git a/shared.gemfile b/shared.gemfile
index bfdfb46..1422bd1 100644
--- a/shared.gemfile
+++ b/shared.gemfile
@@ -14,3 +14,6 @@ if ENV['COVERAGE']
     gem 'simplecov', require: false
   end
 end
+
+# For development/testing; when running as a library, you can pick your own sass compiler
+gem 'dartsass-sprockets'
\ No newline at end of file
diff --git a/spec/gemfiles/rails_4_2.gemfile b/spec/gemfiles/rails_4_2.gemfile
deleted file mode 100644
index 6fc5f89..0000000
--- a/spec/gemfiles/rails_4_2.gemfile
+++ /dev/null
@@ -1,6 +0,0 @@
-source 'https://rubygems.org'
-
-gemspec path: '../..'
-eval_gemfile '../../shared.gemfile'
-
-gem 'rails', '~> 4.2.0'
diff --git a/spec/gemfiles/rails_5_0.gemfile b/spec/gemfiles/rails_5_0.gemfile
deleted file mode 100644
index 1ce822c..0000000
--- a/spec/gemfiles/rails_5_0.gemfile
+++ /dev/null
@@ -1,6 +0,0 @@
-source 'https://rubygems.org'
-
-gemspec path: '../..'
-eval_gemfile '../../shared.gemfile'
-
-gem 'rails', '~> 5.0.2'
diff --git a/spec/gemfiles/rails_5_2.gemfile b/spec/gemfiles/rails_7_1.gemfile
similarity index 79%
rename from spec/gemfiles/rails_5_2.gemfile
rename to spec/gemfiles/rails_7_1.gemfile
index a1443b6..d43f90a 100644
--- a/spec/gemfiles/rails_5_2.gemfile
+++ b/spec/gemfiles/rails_7_1.gemfile
@@ -3,5 +3,5 @@ source 'https://rubygems.org'
 gemspec path: '../..'
 eval_gemfile '../../shared.gemfile'
 
-gem 'rails', '~> 5.2.1'
+gem 'rails', '~> 7.1'