diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index ad5bb71..951deff 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -18,13 +18,16 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: [3.1, 3.2, 3.3]
+        ruby: [3.1, 3.2, 3.3, 3.4]
         gemfile:
         - Gemfile
-        - gemfiles/rails_6_0.gemfile
-        - gemfiles/rails_6_1.gemfile
         - gemfiles/rails_7_0.gemfile
         - gemfiles/rails_7_1.gemfile
+        - gemfiles/rails_7_2.gemfile
+        - gemfiles/rails_8_0.gemfile
+        exclude:
+        - ruby: 3.1
+          gemfile: gemfiles/rails_8_0.gemfile
 
     env:
       BUNDLE_GEMFILE: ${{ matrix.gemfile }}
diff --git a/Appraisals b/Appraisals
index 31d765f..14a815b 100644
--- a/Appraisals
+++ b/Appraisals
@@ -2,4 +2,4 @@
 
 require "appraisal/matrix"
 
-appraisal_matrix(rails: "6.0")
+appraisal_matrix(rails: "7.0")
diff --git a/Gemfile b/Gemfile
index af4e2f9..458ee0a 100644
--- a/Gemfile
+++ b/Gemfile
@@ -26,3 +26,4 @@ gem "concurrent-ruby", "~> 1.3", "< 1.3.5"
 gem "base64", ">= 0.2.0"
 gem "bigdecimal", ">= 3.1"
 gem "mutex_m", ">= 0.3.0"
+gem "drb"
diff --git a/Gemfile.lock b/Gemfile.lock
index 4f26f0a..b29554e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -83,6 +83,7 @@ GEM
     crass (1.0.6)
     date (3.3.3)
     diff-lcs (1.5.1)
+    drb (2.2.1)
     erubi (1.12.0)
     globalid (1.1.0)
       activesupport (>= 5.0)
@@ -226,6 +227,7 @@ DEPENDENCIES
   base64 (>= 0.2.0)
   bigdecimal (>= 3.1)
   concurrent-ruby (~> 1.3, < 1.3.5)
+  drb
   large_text_field!
   minitest (~> 5.1)
   minitest-reporters
diff --git a/gemfiles/rails_6_0.gemfile b/gemfiles/rails_6_0.gemfile
deleted file mode 100644
index 1b4b9d9..0000000
--- a/gemfiles/rails_6_0.gemfile
+++ /dev/null
@@ -1,26 +0,0 @@
-# This file was generated by Appraisal
-
-source "https://rubygems.org"
-
-gem "appraisal"
-gem "appraisal-matrix"
-gem "minitest", "~> 5.1"
-gem "minitest-reporters"
-gem "mysql2"
-gem "pry"
-gem "rspec-expectations"
-gem "rspec-mocks"
-gem "rubocop", require: false
-gem "rubocop-minitest", require: false
-gem "rubocop-rails", require: false
-gem "shoulda", "~> 3.5"
-gem "shoulda-matchers", "~> 3.0"
-gem "test-unit", "~> 3.3"
-gem "warning", require: false
-gem "concurrent-ruby", "~> 1.3", "< 1.3.5"
-gem "base64", ">= 0.2.0"
-gem "bigdecimal", ">= 3.1"
-gem "mutex_m", ">= 0.3.0"
-gem "rails", "~> 6.0.0"
-
-gemspec path: "../"
diff --git a/gemfiles/rails_6_1.gemfile b/gemfiles/rails_6_1.gemfile
deleted file mode 100644
index 9d8e84d..0000000
--- a/gemfiles/rails_6_1.gemfile
+++ /dev/null
@@ -1,26 +0,0 @@
-# This file was generated by Appraisal
-
-source "https://rubygems.org"
-
-gem "appraisal"
-gem "appraisal-matrix"
-gem "minitest", "~> 5.1"
-gem "minitest-reporters"
-gem "mysql2"
-gem "pry"
-gem "rspec-expectations"
-gem "rspec-mocks"
-gem "rubocop", require: false
-gem "rubocop-minitest", require: false
-gem "rubocop-rails", require: false
-gem "shoulda", "~> 3.5"
-gem "shoulda-matchers", "~> 3.0"
-gem "test-unit", "~> 3.3"
-gem "warning", require: false
-gem "concurrent-ruby", "~> 1.3", "< 1.3.5"
-gem "base64", ">= 0.2.0"
-gem "bigdecimal", ">= 3.1"
-gem "mutex_m", ">= 0.3.0"
-gem "rails", "~> 6.1.0"
-
-gemspec path: "../"
diff --git a/gemfiles/rails_7_0.gemfile b/gemfiles/rails_7_0.gemfile
index 56e6ced..210e726 100644
--- a/gemfiles/rails_7_0.gemfile
+++ b/gemfiles/rails_7_0.gemfile
@@ -21,6 +21,7 @@ gem "concurrent-ruby", "~> 1.3", "< 1.3.5"
 gem "base64", ">= 0.2.0"
 gem "bigdecimal", ">= 3.1"
 gem "mutex_m", ">= 0.3.0"
+gem "drb"
 gem "rails", "~> 7.0.0"
 
 gemspec path: "../"
diff --git a/gemfiles/rails_7_1.gemfile b/gemfiles/rails_7_1.gemfile
index 490812e..d7a7414 100644
--- a/gemfiles/rails_7_1.gemfile
+++ b/gemfiles/rails_7_1.gemfile
@@ -21,6 +21,7 @@ gem "concurrent-ruby", "~> 1.3", "< 1.3.5"
 gem "base64", ">= 0.2.0"
 gem "bigdecimal", ">= 3.1"
 gem "mutex_m", ">= 0.3.0"
+gem "drb"
 gem "rails", "~> 7.1.0"
 
 gemspec path: "../"
diff --git a/gemfiles/rails_7_2.gemfile b/gemfiles/rails_7_2.gemfile
index 6b6ac38..75e18ff 100644
--- a/gemfiles/rails_7_2.gemfile
+++ b/gemfiles/rails_7_2.gemfile
@@ -21,6 +21,7 @@ gem "concurrent-ruby", "~> 1.3", "< 1.3.5"
 gem "base64", ">= 0.2.0"
 gem "bigdecimal", ">= 3.1"
 gem "mutex_m", ">= 0.3.0"
+gem "drb"
 gem "rails", "~> 7.2.0"
 
 gemspec path: "../"
diff --git a/gemfiles/rails_8_0.gemfile b/gemfiles/rails_8_0.gemfile
index 1723e09..23ac77f 100644
--- a/gemfiles/rails_8_0.gemfile
+++ b/gemfiles/rails_8_0.gemfile
@@ -21,6 +21,7 @@ gem "concurrent-ruby", "~> 1.3", "< 1.3.5"
 gem "base64", ">= 0.2.0"
 gem "bigdecimal", ">= 3.1"
 gem "mutex_m", ">= 0.3.0"
+gem "drb"
 gem "rails", "~> 8.0.0"
 
 gemspec path: "../"