diff --git a/.circleci/config.yml b/.circleci/config.yml
deleted file mode 100644
index 8032e579..00000000
--- a/.circleci/config.yml
+++ /dev/null
@@ -1,67 +0,0 @@
-version: 2.1
-
-orbs:
-  # Always take the latest version of the orb, this allows us to
-  # run specs against Solidus supported versions only without the need
-  # to change this configuration every time a Solidus version is released
-  # or goes EOL.
-  solidusio_extensions: solidusio/extensions@volatile
-
-jobs:
-  run-specs:
-    parameters:
-      solidus:
-        type: string
-        default: main
-      db:
-        type: string
-        default: "postgres"
-      ruby:
-        type: string
-        default: "3.2"
-    executor:
-      name: solidusio_extensions/<< parameters.db >>
-      ruby_version: << parameters.ruby >>
-    steps:
-      - checkout
-      - solidusio_extensions/run-tests-solidus-<< parameters.solidus >>
-  lint-code:
-    executor:
-      name: solidusio_extensions/sqlite-memory
-      ruby_version: 2.5
-    steps:
-      - solidusio_extensions/lint-code
-
-workflows:
-  "Run specs on supported Solidus versions":
-    jobs:
-      - run-specs:
-          name: &name "run-specs-solidus-<< matrix.solidus >>-ruby-<< matrix.ruby >>-db-<< matrix.db >>"
-          matrix:
-            parameters: { solidus: ["main"], ruby: ["3.2"], db: ["postgres"] }
-      - run-specs:
-          name: *name
-          matrix:
-            parameters: { solidus: ["current"], ruby: ["3.1"], db: ["mysql"] }
-      - run-specs:
-          name: *name
-          matrix:
-            parameters: { solidus: ["older"], ruby: ["3.0"], db: ["sqlite"] }
-
-  "Weekly run specs against main":
-    triggers:
-      - schedule:
-          cron: "0 0 * * 4" # every Thursday
-          filters:
-            branches:
-              only:
-                - main
-    jobs:
-      - run-specs:
-          name: *name
-          matrix:
-            parameters: { solidus: ["main"], ruby: ["3.2"], db: ["postgres"] }
-      - run-specs:
-          name: *name
-          matrix:
-            parameters: { solidus: ["current"], ruby: ["3.1"], db: ["mysql"] }
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
new file mode 100644
index 00000000..308f16ef
--- /dev/null
+++ b/.github/workflows/test.yml
@@ -0,0 +1,70 @@
+name: Test
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+  schedule:
+    - cron: "0 0 * * 4" # every Thursday
+
+concurrency:
+  group: test-${{ github.ref_name }}
+  cancel-in-progress: ${{ github.ref_name != 'main' }}
+
+permissions:
+  contents: read
+
+jobs:
+  rspec:
+    name: Solidus ${{ matrix.solidus-branch }}, Rails ${{ matrix.rails-version }} and Ruby ${{ matrix.ruby-version }} on ${{ matrix.database }}
+    runs-on: ubuntu-24.04
+    strategy:
+      fail-fast: true
+      matrix:
+        rails-version:
+          - "7.0"
+          - "7.1"
+          - "7.2"
+        ruby-version:
+          - "3.1"
+          - "3.4"
+        solidus-branch:
+          - "v4.1"
+          - "v4.2"
+          - "v4.3"
+          - "v4.4"
+        database:
+          - "postgresql"
+          - "mysql"
+          - "sqlite"
+        exclude:
+          - rails-version: "7.2"
+            solidus-branch: "v4.3"
+          - rails-version: "7.2"
+            solidus-branch: "v4.2"
+          - rails-version: "7.2"
+            solidus-branch: "v4.1"
+          - rails-version: "7.1"
+            solidus-branch: "v4.2"
+          - rails-version: "7.1"
+            solidus-branch: "v4.1"
+          - ruby-version: "3.4"
+            rails-version: "7.0"
+    env:
+      TEST_RESULTS_PATH: coverage/coverage.xml
+    steps:
+      - uses: actions/checkout@v4
+      - name: Run extension tests
+        uses: solidusio/test-solidus-extension@main
+        with:
+          database: ${{ matrix.database }}
+          rails-version: ${{ matrix.rails-version }}
+          ruby-version: ${{ matrix.ruby-version }}
+          solidus-branch: ${{ matrix.solidus-branch }}
+      - name: Upload coverage reports to Codecov
+        uses: codecov/codecov-action@v5
+        continue-on-error: true
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          files: ${{ env.TEST_RESULTS_PATH }}
diff --git a/Gemfile b/Gemfile
index ba4aac4f..30cfa727 100644
--- a/Gemfile
+++ b/Gemfile
@@ -7,21 +7,10 @@ branch = ENV.fetch('SOLIDUS_BRANCH', 'main')
 gem 'solidus', github: 'solidusio/solidus', branch: branch
 
 # The solidus_frontend gem has been pulled out since v3.2
-if branch >= 'v3.2'
-  gem 'solidus_frontend'
-elsif branch == 'main'
-  gem 'solidus_frontend', github: 'solidusio/solidus_frontend'
-else
-  gem 'solidus_frontend', github: 'solidusio/solidus', branch: branch
-end
-
-# Needed to help Bundler figure out how to resolve dependencies,
-# otherwise it takes forever to resolve them.
-# See https://github.com/bundler/bundler/issues/6677
-gem 'rails', '>0.a'
+gem 'solidus_frontend'
 
-# Provides basic authentication functionality for testing parts of your engine
-gem 'solidus_auth_devise'
+rails_version = ENV.fetch('RAILS_VERSION', '7.2')
+gem 'rails', "~> #{rails_version}"
 
 case ENV['DB']
 when 'mysql'
@@ -29,18 +18,15 @@ when 'mysql'
 when 'postgresql'
   gem 'pg'
 else
-  gem 'sqlite3'
+  if rails_version <= "7.2"
+    gem 'sqlite3', "~> 1.7"
+  else
+    gem 'sqlite3', "~> 2.0"
+  end
 end
 
 gemspec
 
-if Gem::Version.new(RUBY_VERSION) >= Gem::Version.new('3')
-  # Fix for Rails 7+ / Ruby 3+, see https://stackoverflow.com/a/72474475
-  gem 'net-imap', require: false
-  gem 'net-pop', require: false
-  gem 'net-smtp', require: false
-end
-
 # Use a local Gemfile to include development dependencies that might not be
 # relevant for the project or for other contributors, e.g. pry-byebug.
 #
diff --git a/app/decorators/models/solidus_subscriptions/spree/user/have_many_subscriptions.rb b/app/decorators/models/solidus_subscriptions/spree/user/have_many_subscriptions.rb
index 1fb4cdf6..9fee356a 100644
--- a/app/decorators/models/solidus_subscriptions/spree/user/have_many_subscriptions.rb
+++ b/app/decorators/models/solidus_subscriptions/spree/user/have_many_subscriptions.rb
@@ -16,8 +16,8 @@ def self.prepended(base)
         end
 
         def subscriptions_attributes=(params)
-          ::Spree::Deprecation.warn(
-            'Creating or updating subscriptions through Spree::User nested attributes is deprecated. ' \
+          ::Spree.deprecator.warn(
+            "Creating or updating subscriptions through #{::Spree.user_class} nested attributes is deprecated. " \
             'Please use subscriptions APIs directly.'
           )
           super
@@ -27,4 +27,4 @@ def subscriptions_attributes=(params)
   end
 end
 
-Spree.user_class.prepend(SolidusSubscriptions::Spree::User::HaveManySubscriptions)
+::Spree.user_class.prepend(SolidusSubscriptions::Spree::User::HaveManySubscriptions)
diff --git a/lib/generators/solidus_subscriptions/install/install_generator.rb b/lib/generators/solidus_subscriptions/install/install_generator.rb
index 2081deab..faa11391 100644
--- a/lib/generators/solidus_subscriptions/install/install_generator.rb
+++ b/lib/generators/solidus_subscriptions/install/install_generator.rb
@@ -19,6 +19,7 @@ def add_javascripts
 
       def copy_starter_frontend_files
         return if options[:frontend] != 'starter'
+        return unless File.exist?(Rails.root.join('app/views/cart_line_items/_product_submit.html.erb'))
 
         copy_file 'app/views/cart_line_items/_subscription_fields.html.erb'
         prepend_to_file 'app/views/cart_line_items/_product_submit.html.erb', "<%= render 'cart_line_items/subscription_fields' %>\n"
diff --git a/spec/controllers/spree/api/users_controller_spec.rb b/spec/controllers/spree/api/users_controller_spec.rb
index 0a7d6141..f4bf4844 100644
--- a/spec/controllers/spree/api/users_controller_spec.rb
+++ b/spec/controllers/spree/api/users_controller_spec.rb
@@ -40,7 +40,7 @@
 
     it 'updates the subscription line items' do
       allow(::Spree::Deprecation).to receive(:warn).with(a_string_matching(
-        'Creating or updating subscriptions through Spree::User nested attributes is deprecated'
+        "Creating or updating subscriptions through #{Spree.user_class} nested attributes is deprecated"
       ))
       update_user
       line_item = subscription.line_items.reload.first
diff --git a/spec/decorators/models/solidus_subscriptions/spree/user/have_many_subscriptions_spec.rb b/spec/decorators/models/solidus_subscriptions/spree/user/have_many_subscriptions_spec.rb
index 4047b010..ed8aea0f 100644
--- a/spec/decorators/models/solidus_subscriptions/spree/user/have_many_subscriptions_spec.rb
+++ b/spec/decorators/models/solidus_subscriptions/spree/user/have_many_subscriptions_spec.rb
@@ -3,7 +3,7 @@
 require 'spec_helper'
 
 RSpec.describe SolidusSubscriptions::Spree::User::HaveManySubscriptions, type: :model do
-  subject(:user) { Spree::User.new }
+  subject(:user) { Spree.user_class.new }
 
   it { is_expected.to have_many :subscriptions }
   it { is_expected.to accept_nested_attributes_for :subscriptions }
@@ -16,7 +16,7 @@
 
       expect(::Spree::Deprecation)
         .to have_received(:warn)
-        .with(/Creating or updating subscriptions through Spree::User nested attributes is deprecated/)
+        .with(/Creating or updating subscriptions through #{Spree.user_class} nested attributes is deprecated/)
     end
   end
 end