diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 09eda75..8028045 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -11,11 +11,13 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        ruby: ['2.6', '2.7', '3.0', '3.1']
-        gemfile: ['rails_5.0', 'rails_5.1', 'rails_5.2', 'rails_6.0', 'rails_6.1', 'rails_7.0']
+        ruby: ['2.6', '2.7', '3.0', '3.1', '3.2', '3.3', '3.4']
+        gemfile: ['rails_5.0', 'rails_5.1', 'rails_5.2', 'rails_6.0', 'rails_6.1', 'rails_7.0', 'rails_7.1']
         exclude:
           - ruby: '2.6'
             gemfile: 'rails_7.0'
+          - ruby: '2.6'
+            gemfile: 'rails_7.1'
           - ruby: '3.0'
             gemfile: 'rails_5.0'
           - ruby: '3.0'
@@ -28,6 +30,24 @@ jobs:
             gemfile: 'rails_5.1'
           - ruby: '3.1'
             gemfile: 'rails_5.2'
+          - ruby: '3.2'
+            gemfile: 'rails_5.0'
+          - ruby: '3.2'
+            gemfile: 'rails_5.1'
+          - ruby: '3.2'
+            gemfile: 'rails_5.2'
+          - ruby: '3.3'
+            gemfile: 'rails_5.0'
+          - ruby: '3.3'
+            gemfile: 'rails_5.1'
+          - ruby: '3.3'
+            gemfile: 'rails_5.2'
+          - ruby: '3.4'
+            gemfile: 'rails_5.0'
+          - ruby: '3.4'
+            gemfile: 'rails_5.1'
+          - ruby: '3.4'
+            gemfile: 'rails_5.2'
     env:
       BUNDLE_GEMFILE: ${{ github.workspace }}/gemfiles/${{ matrix.gemfile }}.gemfile
 
diff --git a/gemfiles/rails_5.0.gemfile b/gemfiles/rails_5.0.gemfile
index 7fe582a..925b34b 100644
--- a/gemfiles/rails_5.0.gemfile
+++ b/gemfiles/rails_5.0.gemfile
@@ -4,5 +4,6 @@ source 'https://rubygems.org'
 
 gem 'activerecord', '~> 5.0.0'
 gem 'sqlite3', '~> 1.3.0'
+gem 'database_cleaner', '~> 1.99'
 
 gemspec path: '../'
diff --git a/gemfiles/rails_5.1.gemfile b/gemfiles/rails_5.1.gemfile
index 1f35e25..dc5db07 100644
--- a/gemfiles/rails_5.1.gemfile
+++ b/gemfiles/rails_5.1.gemfile
@@ -3,6 +3,6 @@
 source 'https://rubygems.org'
 
 gem 'activerecord', '~> 5.1.0'
-gem 'sqlite3', '~> 1.3.0'
+gem 'sqlite3', '~> 1.4'
 
 gemspec path: '../'
diff --git a/gemfiles/rails_7.1.gemfile b/gemfiles/rails_7.1.gemfile
new file mode 100644
index 0000000..7f6612a
--- /dev/null
+++ b/gemfiles/rails_7.1.gemfile
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+source 'https://rubygems.org'
+
+gem 'activerecord', '~> 7.1.3'
+
+if Gem::Version.new(RUBY_VERSION) >= Gem::Version.new('3.0.0')
+  gem 'sqlite3', '~> 2.0'
+else
+  gem 'sqlite3', '~> 1.4'
+end
+
+gemspec path: '../'
diff --git a/imyou.gemspec b/imyou.gemspec
index b683472..6511509 100644
--- a/imyou.gemspec
+++ b/imyou.gemspec
@@ -25,13 +25,17 @@ Gem::Specification.new do |spec|
   spec.require_paths = ['lib']
   spec.required_ruby_version = '>= 2.6'
 
-  spec.add_dependency 'activerecord', '< 7.1.0', '>= 5.0.0'
-  spec.add_development_dependency 'database_cleaner', '~> 2.0'
+  spec.add_dependency 'activerecord', '< 7.2.0', '>= 5.0.0'
+  spec.add_development_dependency 'database_cleaner', '< 3.0', '>= 1.99.0'
   spec.add_development_dependency 'rake', '~> 13.0'
   spec.add_development_dependency 'rubocop', '~> 1.24'
   spec.add_development_dependency 'rubocop-minitest', '~> 0.17'
   spec.add_development_dependency 'rubocop-performance', '~> 1.13'
   spec.add_development_dependency 'rubocop-rake', '~> 0.6'
-  spec.add_development_dependency 'sqlite3', '~> 1.3'
+  spec.add_development_dependency 'sqlite3', '< 3.0', '>= 1.3'
+  spec.add_development_dependency 'concurrent-ruby', '1.3.4'
+  spec.add_development_dependency 'mutex_m', '~> 0.1'
+  spec.add_development_dependency 'bigdecimal', '~> 3.0'
+  spec.add_development_dependency 'base64', '~> 0.1'
   spec.metadata['rubygems_mfa_required'] = 'true'
 end
diff --git a/lib/imyou/models.rb b/lib/imyou/models.rb
index 19d6d2d..e3197d0 100644
--- a/lib/imyou/models.rb
+++ b/lib/imyou/models.rb
@@ -18,7 +18,11 @@ def has_imyou(name_column = nil)
 
         scope :with_nicknames, -> { preload(:imyou_nicknames) }
 
-        scope :match_by_nickname, lambda { |nickname, with_name_column: true|
+        # 本来はscopeで定義するべきだが、Ruby 3.2以降とActiveRecord 6.1系ではエラーになるため、
+        # 苦肉の策で特異メソッドとして定義する。
+        # Rails 6.1のサポートを終了したら、scopeに戻すこと。
+        # @see https://qiita.com/usk0513/items/c2968733415c806f56fc
+        define_singleton_method(:match_by_nickname) do |nickname, with_name_column: true|
           if Gem::Version.new(ActiveRecord.version) >= Gem::Version.new(5)
             records = left_outer_joins(:imyou_nicknames).where(Imyou::Nickname.arel_table[:name].eq(nickname))
             unless name_column.nil? || with_name_column == false
@@ -47,9 +51,9 @@ def has_imyou(name_column = nil)
                       end
           end
           records
-        }
+        end
 
-        scope :partial_match_by_nickname, lambda { |nickname, with_name_column: true|
+        define_singleton_method(:partial_match_by_nickname) do |nickname, with_name_column: true|
           if Gem::Version.new(ActiveRecord.version) >= Gem::Version.new(5)
             records = left_outer_joins(:imyou_nicknames).
                       where(Imyou::Nickname.arel_table[:name].
@@ -82,7 +86,7 @@ def has_imyou(name_column = nil)
                       end
           end
           records
-        }
+        end
 
         alias_method :save_with_nicknames, :save
         alias_method :save_with_nicknames!, :save!
diff --git a/lib/imyou/version.rb b/lib/imyou/version.rb
index 091e888..c9dd834 100644
--- a/lib/imyou/version.rb
+++ b/lib/imyou/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Imyou
-  VERSION = '1.4.3'
+  VERSION = '1.4.4'
 end
diff --git a/test/nickname_test.rb b/test/nickname_test.rb
index 20d5ca8..029acbd 100644
--- a/test/nickname_test.rb
+++ b/test/nickname_test.rb
@@ -64,7 +64,7 @@
 
       describe 'If with_name_column = false' do
         it 'should not search by users.name' do
-          expect(User.match_by_nickname('user_name', with_name_column: false)).wont_be :exists?
+          expect(User.match_by_nickname("user_name", with_name_column: false)).wont_be :exists?
         end
       end
     end
diff --git a/test/test_helper.rb b/test/test_helper.rb
index af4087b..cede272 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -3,7 +3,8 @@
 require 'minitest/autorun'
 require 'active_record'
 
-require 'database_cleaner/active_record'
+# database_cleaner 1～2系のどちらでも動くようにするため、パスを修正
+require 'database_cleaner'
 require 'imyou'
 
 Dir["#{Dir.pwd}/test/internal/app/models/*.rb"].sort.each { |f| require f }
@@ -49,19 +50,21 @@ class Spec
 end
 
 # @see https://stackoverflow.com/questions/20329387/how-to-assert-the-contents-of-an-array-indifferent-of-the-ordering
-module MiniTest
+module Minitest
   module Assertions
     def assert_matched_arrays(exp, act)
       exp_ary = exp.to_ary
+
       assert_kind_of Array, exp_ary
       act_ary = act.to_ary
+
       assert_kind_of Array, act_ary
       assert_equal exp_ary.sort, act_ary.sort
     end
   end
 end
 
-module MiniTest
+module Minitest
   module Expectations
     infect_an_assertion :assert_matched_arrays, :must_match_array
   end