diff --git a/.github/workflows/tcr.yml b/.github/workflows/tcr.yml
index fb8244e..361ccaa 100644
--- a/.github/workflows/tcr.yml
+++ b/.github/workflows/tcr.yml
@@ -7,33 +7,26 @@ on:
 
 jobs:
   test:
-    name: Test
+    name: "Test: Ruby ${{ matrix.ruby }}"
     runs-on: ubuntu-latest
-
     strategy:
+      fail-fast: false
       matrix:
         ruby:
-          - "2.0.0"
-          - "2.1.9"
-          - "2.2.10"
-          - "2.3.7"
-          - "2.4.4"
-          - "2.5.1"
-          - "2.7.3"
-          - "3.0.1"
-
+          - "2.7"
+          - "3.0"
+          - "3.1"
     steps:
       - uses: actions/checkout@v2
-
-      - name: Initial setup
+      - name: Set up Ruby
         uses: ruby/setup-ruby@v1
         with:
           ruby-version: ${{ matrix.ruby }}
-
-      - name: Install dependencies
-        run: bundle install
-
-      - name: Run tests
+          # runs 'bundle install' and caches installed gems automatically
+          bundler-cache: true
+      - name: Ruby Version
+        run: ruby --version
+      - name: Run Tests
         run: bundle exec rspec
 
   testall:
diff --git a/.gitignore b/.gitignore
index b639e8c..d91b913 100644
--- a/.gitignore
+++ b/.gitignore
@@ -16,3 +16,4 @@ test/tmp
 test/version_tmp
 tmp
 /.idea
+.tool-versions
diff --git a/.rvmrc b/.rvmrc
deleted file mode 100644
index 77cc2fe..0000000
--- a/.rvmrc
+++ /dev/null
@@ -1 +0,0 @@
-rvm use 1.9.3@tcr --create
diff --git a/Gemfile b/Gemfile
index d3d1a19..df4e9a4 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,4 +1,8 @@
-source 'https://rubygems.org'
+source "https://rubygems.org"
 
-# Specify your gem's dependencies in tcr.gemspec
 gemspec
+
+gem "rspec"
+gem "mail"
+gem "net-ldap"
+gem "mime-types"
diff --git a/Rakefile b/Rakefile
index 27e09f4..d13b715 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,4 +1,4 @@
 require "bundler/gem_tasks"
 require "rspec/core/rake_task"
-RSpec::Core::RakeTask.new('spec')
+RSpec::Core::RakeTask.new("spec")
 task :default => :spec
diff --git a/tcr.gemspec b/tcr.gemspec
index ceb2ae1..27a661d 100644
--- a/tcr.gemspec
+++ b/tcr.gemspec
@@ -16,10 +16,4 @@ Gem::Specification.new do |gem|
   gem.executables   = gem.files.grep(%r{^bin/}).map{ |f| File.basename(f) }
   gem.test_files    = gem.files.grep(%r{^(test|spec|features)/})
   gem.require_paths = ["lib"]
-
-  gem.add_development_dependency "rspec"
-  gem.add_development_dependency "mail"
-  gem.add_development_dependency "net-ldap"
-  gem.add_development_dependency "mime-types", "~>2.0"
-  gem.add_development_dependency "geminabox"
 end