diff --git a/.circleci/config.yml b/.circleci/config.yml
index bbfb4836..c989d34d 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -46,9 +46,6 @@ jobs:
             export VAULT_VERSION=<< parameters.vault-version >>
             export RAILS_VERSION=<< parameters.rails-version >>
             ruby --version
-            # Downgrade Bundler to 1.x
-            gem uninstall -v '>= 2' -i $(rvm gemdir)@global -ax bundler || true
-            gem install bundler -v '< 2'
             bundle -v
             bundle install --jobs=4 --retry=3 --path=vendor/bundle
             bundle exec rake app:db:create
@@ -79,7 +76,7 @@ workflows:
           matrix:
             parameters:
               ruby-version: ["2.6", "2.5"]
-              rails-version: ["6.0.0", "5.2.0", "5.1.0", "5.0.0", "4.2.0"]
+              rails-version: ["6.0.0", "5.2.0", "5.1.0", "5.0.0"]
               vault-version: ["1.4.2", "1.4.1", "1.4.0", "1.3.6"]
           name: test-ruby-<< matrix.ruby-version >>-rails-<< matrix.rails-version >>-vault-<< matrix.vault-version >>
       - build-release:
diff --git a/spec/integration/rails_spec.rb b/spec/integration/rails_spec.rb
index ad3523cc..44005c05 100644
--- a/spec/integration/rails_spec.rb
+++ b/spec/integration/rails_spec.rb
@@ -97,6 +97,11 @@
       person.name = "Cinderella"
       person.save!
     end
+
+    it "does not register a Vault attribute as necessarily being backed by a column" do
+      expect(Person.attribute_names).to include("ssn")
+      expect(Person.column_names).not_to include("ssn")
+    end
   end
 
   context "lazy decrypt" do
diff --git a/vault.gemspec b/vault.gemspec
index fce57beb..0bfa74c8 100644
--- a/vault.gemspec
+++ b/vault.gemspec
@@ -17,7 +17,7 @@ Gem::Specification.new do |s|
   s.files = Dir["{app,config,db,lib}/**/*", "LICENSE", "Rakefile", "README.md"]
   s.test_files = Dir["spec/**/*"]
 
-  s.add_dependency "rails", ">= 4.2"
+  s.add_dependency "rails", ">= 5.0"
   s.add_dependency "vault", "~> 0.14"
 
   s.add_development_dependency "bundler"