diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 62cc813..d9d96bb 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -10,8 +10,23 @@ jobs:
   build:
     runs-on: ubuntu-latest
     strategy:
+      fail-fast: false
       matrix:
-        ruby: ["3.0", "3.1", "3.2", "3.3"]
+        ruby:
+          - "3.0"
+          - "3.1"
+          - "3.2"
+          - "3.3"
+        gemfile:
+          - Gemfile
+          - gemfiles/Gemfile-rails-main
+          - gemfiles/Gemfile-rails-7-0
+          - gemfiles/Gemfile-rails-6-1
+        exclude:
+          - gemfile: gemfiles/Gemfile-rails-main
+            ruby: "3.0"
+    env:
+      BUNDLE_GEMFILE: ${{ matrix.gemfile }}
     steps:
       - uses: actions/checkout@v4
       - uses: ruby/setup-ruby@v1
diff --git a/.gitignore b/.gitignore
index 24cc8bb..6151702 100644
--- a/.gitignore
+++ b/.gitignore
@@ -10,3 +10,4 @@ Gemfile.lock
 .yardoc
 doc
 coverage
+gemfiles/*.lock
diff --git a/db/migrate/20171104221735_create_passwordless_sessions.rb b/db/migrate/20171104221735_create_passwordless_sessions.rb
index acfede0..32734fb 100644
--- a/db/migrate/20171104221735_create_passwordless_sessions.rb
+++ b/db/migrate/20171104221735_create_passwordless_sessions.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-class CreatePasswordlessSessions < ActiveRecord::Migration[5.1]
+class CreatePasswordlessSessions < ActiveRecord::Migration[6.0]
   def change
     create_table(:passwordless_sessions) do |t|
       t.belongs_to(
diff --git a/gemfiles/Gemfile-rails-6-1 b/gemfiles/Gemfile-rails-6-1
new file mode 100644
index 0000000..697b927
--- /dev/null
+++ b/gemfiles/Gemfile-rails-6-1
@@ -0,0 +1,18 @@
+source "https://rubygems.org"
+
+gemspec(path: "..")
+
+gem "rails", "~> 6.1.0"
+gem "puma"
+gem "sqlite3", "~> 1.4"
+gem "yard"
+
+group :test do
+  gem "capybara", require: false
+  gem "codecov", require: false
+  gem "minitest"
+  gem "rails-controller-testing"
+end
+
+# vim: ft=ruby
+
diff --git a/gemfiles/Gemfile-rails-7-0 b/gemfiles/Gemfile-rails-7-0
new file mode 100644
index 0000000..0ac1d5a
--- /dev/null
+++ b/gemfiles/Gemfile-rails-7-0
@@ -0,0 +1,17 @@
+source "https://rubygems.org"
+
+gemspec(path: "..")
+
+gem "rails", "~> 7.0.0"
+gem "puma"
+gem "sqlite3", "~> 1.4"
+gem "yard"
+
+group :test do
+  gem "capybara", require: false
+  gem "codecov", require: false
+  gem "minitest"
+  gem "rails-controller-testing"
+end
+
+# vim: ft=ruby
diff --git a/gemfiles/Gemfile-rails-main b/gemfiles/Gemfile-rails-main
new file mode 100644
index 0000000..31d7c59
--- /dev/null
+++ b/gemfiles/Gemfile-rails-main
@@ -0,0 +1,18 @@
+source "https://rubygems.org"
+
+gemspec(path: "..")
+
+gem "rails", github: "rails/rails", branch: "main"
+gem "puma"
+gem "sqlite3", "~> 1.4"
+gem "yard"
+
+group :test do
+  gem "capybara", require: false
+  gem "codecov", require: false
+  gem "minitest"
+  gem "rails-controller-testing"
+end
+
+# vim: ft=ruby
+
diff --git a/test/dummy/app/controllers/admin/sessions_controller.rb b/test/dummy/app/controllers/admin/sessions_controller.rb
index ef03360..6c5b9fb 100644
--- a/test/dummy/app/controllers/admin/sessions_controller.rb
+++ b/test/dummy/app/controllers/admin/sessions_controller.rb
@@ -1,5 +1,2 @@
-
-class Admin
-  class SessionsController < Passwordless::SessionsController
-  end
+class Admin::SessionsController < Passwordless::SessionsController
 end
diff --git a/test/dummy/config/application.rb b/test/dummy/config/application.rb
index 1850537..dc07aa9 100644
--- a/test/dummy/config/application.rb
+++ b/test/dummy/config/application.rb
@@ -24,10 +24,19 @@
 
 module Dummy
   class Application < Rails::Application
-    config.load_defaults 7.0
+    config.load_defaults Rails::VERSION::STRING.to_f
 
     config.action_mailer.default_url_options = {host: "localhost", port: "3000"}
     routes.default_url_options[:host] = "localhost:3000"
-    config.i18n.available_locales = %i[en test]
+
+    case Rails::VERSION::MAJOR
+    when 6
+      I18n.available_locales = %i[en test]
+    when 7..Float::INFINITY
+      config.i18n.available_locales = %i[en test]
+
+      # Silence deprecation warning
+      config.active_support.cache_format_version = 7.0
+    end
   end
 end
diff --git a/test/dummy/db/migrate/20230621085550_create_users_and_admins.rb b/test/dummy/db/migrate/20230621085550_create_users_and_admins.rb
index d1ee766..519d981 100644
--- a/test/dummy/db/migrate/20230621085550_create_users_and_admins.rb
+++ b/test/dummy/db/migrate/20230621085550_create_users_and_admins.rb
@@ -1,4 +1,4 @@
-class CreateUsersAndAdmins < ActiveRecord::Migration[7.0]
+class CreateUsersAndAdmins < ActiveRecord::Migration[6.0]
   def change
     create_table(:admins) do |t|
       t.string(:email)
diff --git a/test/test_helper.rb b/test/test_helper.rb
index fd9a9f1..336a81b 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -23,14 +23,6 @@
 # to be shown.
 Minitest.backtrace_filter = Minitest::BacktraceFilter.new
 
-# Load fixtures from the engine
-if ActiveSupport::TestCase.respond_to?(:fixture_paths=)
-  ActiveSupport::TestCase.fixture_paths = [File.expand_path("../fixtures", __FILE__)]
-  ActionDispatch::IntegrationTest.fixture_paths = ActiveSupport::TestCase.fixture_paths
-  ActiveSupport::TestCase.file_fixture_path = ActiveSupport::TestCase.fixture_paths.first + "/files"
-  ActiveSupport::TestCase.fixtures(:all)
-end
-
 def Minitest.filter_backtrace(bt)
   bt.select { |line| line !~ %r{/gems/} }
 end
@@ -64,14 +56,42 @@ def with_config(options)
   # This can be used when you change the`parent_mailer` config option and need
   # it load a different parent class.
   def reload_mailer!
+    return unless defined?(Passwordless::Mailer)
     Passwordless.send(:remove_const, :Mailer)
-    load File.expand_path("../../app/mailers/passwordless/mailer.rb", __FILE__)
+    load(File.expand_path("../../app/mailers/passwordless/mailer.rb", __FILE__))
   end
 
   def reload_controller!
+    return unless defined?(Passwordless::SessionsController)
     Passwordless.send(:remove_const, :SessionsController)
-    load File.expand_path("../../app/controllers/passwordless/sessions_controller.rb", __FILE__)
+    load(File.expand_path("../../app/controllers/passwordless/sessions_controller.rb", __FILE__))
   end
 end
 
 include(WithConfig)
+
+module FixturePaths
+  def self.included(base)
+    base.class_eval do
+      fixture_path_ = File.expand_path("./fixtures", __dir__)
+
+      if respond_to?(:fixture_paths=)
+        self.fixture_paths = [fixture_path_]
+      elsif respond_to?(:fixture_path=)
+        self.fixture_path = fixture_path_
+      else
+        self.file_fixture_path = "#{fixture_path_}/files"
+      end
+
+      fixtures(:all)
+    end
+  end
+end
+
+class ActionDispatch::IntegrationTest
+  include FixturePaths
+end
+
+class ActiveSupport::TestCase
+  include FixturePaths
+end