diff --git a/.travis.yml b/.travis.yml
index 24df353..19deb48 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,7 +12,6 @@ rvm:
   - jruby-9.2.13.0
 
 gemfile:
-  - gemfiles/rails_4.2.10.gemfile
-  - gemfiles/rails_5.0.7.gemfile
-  - gemfiles/rails_5.1.6.gemfile
-  - gemfiles/rails_5.2.0.gemfile
+  - gemfiles/rails_5.1.7.gemfile
+  - gemfiles/rails_5.2.4.gemfile
+  - gemfiles/rails_6.0.3.gemfile
diff --git a/Appraisals b/Appraisals
index 547463b..a38607c 100644
--- a/Appraisals
+++ b/Appraisals
@@ -1,10 +1,9 @@
 # frozen_string_literal: true
 
 RAILS_VERSIONS = %w[
-  4.2.10
-  5.0.7
-  5.1.6
-  5.2.0
+  5.1.7
+  5.2.4
+  6.0.3
 ].freeze
 
 RAILS_VERSIONS.each do |version|
diff --git a/bin/appraisal b/bin/appraisal
new file mode 100755
index 0000000..0e7ba65
--- /dev/null
+++ b/bin/appraisal
@@ -0,0 +1,29 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'appraisal' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require "pathname"
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../../Gemfile",
+  Pathname.new(__FILE__).realpath)
+
+bundle_binstub = File.expand_path("../bundle", __FILE__)
+
+if File.file?(bundle_binstub)
+  if File.read(bundle_binstub, 300) =~ /This file was generated by Bundler/
+    load(bundle_binstub)
+  else
+    abort("Your `bin/bundle` was not generated by Bundler, so this binstub cannot run.
+Replace `bin/bundle` by running `bundle binstubs bundler --force`, then run this command again.")
+  end
+end
+
+require "rubygems"
+require "bundler/setup"
+
+load Gem.bin_path("appraisal", "appraisal")
diff --git a/gemfiles/rails_4.2.10.gemfile b/gemfiles/rails_4.2.10.gemfile
deleted file mode 100644
index 5f5760b..0000000
--- a/gemfiles/rails_4.2.10.gemfile
+++ /dev/null
@@ -1,7 +0,0 @@
-# This file was generated by Appraisal
-
-source "https://rubygems.org"
-
-gem "activejob", "4.2.10"
-
-gemspec path: "../"
diff --git a/gemfiles/rails_5.0.7.gemfile b/gemfiles/rails_5.1.7.gemfile
similarity index 78%
rename from gemfiles/rails_5.0.7.gemfile
rename to gemfiles/rails_5.1.7.gemfile
index a12cb78..13287c1 100644
--- a/gemfiles/rails_5.0.7.gemfile
+++ b/gemfiles/rails_5.1.7.gemfile
@@ -2,6 +2,6 @@
 
 source "https://rubygems.org"
 
-gem "activejob", "5.0.7"
+gem "activejob", "5.1.7"
 
 gemspec path: "../"
diff --git a/gemfiles/rails_5.1.6.gemfile b/gemfiles/rails_5.2.4.gemfile
similarity index 78%
rename from gemfiles/rails_5.1.6.gemfile
rename to gemfiles/rails_5.2.4.gemfile
index bf83d6b..fb9db73 100644
--- a/gemfiles/rails_5.1.6.gemfile
+++ b/gemfiles/rails_5.2.4.gemfile
@@ -2,6 +2,6 @@
 
 source "https://rubygems.org"
 
-gem "activejob", "5.1.6"
+gem "activejob", "5.2.4"
 
 gemspec path: "../"
diff --git a/gemfiles/rails_5.2.0.gemfile b/gemfiles/rails_6.0.3.gemfile
similarity index 78%
rename from gemfiles/rails_5.2.0.gemfile
rename to gemfiles/rails_6.0.3.gemfile
index 794b610..cbb920e 100644
--- a/gemfiles/rails_5.2.0.gemfile
+++ b/gemfiles/rails_6.0.3.gemfile
@@ -2,6 +2,6 @@
 
 source "https://rubygems.org"
 
-gem "activejob", "5.2.0"
+gem "activejob", "6.0.3"
 
 gemspec path: "../"