diff --git a/.github/workflows/build_and_test.yml b/.github/workflows/build_and_test.yml
index 56d38f0..c5bacb1 100644
--- a/.github/workflows/build_and_test.yml
+++ b/.github/workflows/build_and_test.yml
@@ -7,17 +7,19 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        ruby: [ '2.5', '2.6.x', '2.x']
-    name: Test gem in ruby version ${{ matrix.ruby }}
+        ruby: [ '2.5', '2.6.5']
+    name: Test gem in ruby v${{ matrix.ruby }}
+    container:
+      image: ruby:${{ matrix.ruby }}-alpine
     steps:
     - uses: actions/checkout@v1
-    - name: Set up Ruby ${{ matrix.ruby }}
-      uses: actions/setup-ruby@v1
-      with:
-        ruby-version: ${{ matrix.ruby }}
+    - name: Install make and gcc
+      run: |
+        apk add --update make
+        apk add build-base
     - name: Build with dependencies
       run: |
-        gem install bundler -v 1.17
+        gem install bundler -v 2.1
         bundle install
     - name: Test with rspec
       run: |
diff --git a/.gitignore b/.gitignore
index 46f276e..4f9f3f1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,6 +4,7 @@
 /spec/reports/
 /tmp/
 .DS_Store
+/.tool-versions/
 
 # Gemfile.lock should not be under version control
 # https://yehudakatz.com/2010/12/16/clarifying-the-roles-of-the-gemspec-and-gemfile/
diff --git a/.rubocop.yml b/.rubocop.yml
index cc63f2d..a9bf9b5 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,10 +1,13 @@
+AllCops:
+  TargetRubyVersion: 2.5
+
 Style/Documentation:
   Enabled: false
 
 Style/FrozenStringLiteralComment:
   Enabled: false
 
-Metrics/LineLength:
+Layout/LineLength:
   Max: 120
   IgnoreCopDirectives: true
 
diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index 4b9a1f6..7cfb717 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1,6 +1,6 @@
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2017-04-18 13:12:12 -0700 using RuboCop version 0.48.1.
+# on 2019-12-18 15:48:47 -0800 using RuboCop version 0.78.0.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
@@ -8,14 +8,9 @@
 
 # Offense count: 2
 Metrics/AbcSize:
-  Max: 29
-
-# Offense count: 3
-# Configuration parameters: CountComments.
-Metrics/MethodLength:
   Max: 19
 
-# Offense count: 1
-# Configuration parameters: CountComments.
-Metrics/ModuleLength:
-  Max: 111
+# Offense count: 2
+# Configuration parameters: CountComments, ExcludedMethods.
+Metrics/MethodLength:
+  Max: 18
\ No newline at end of file
diff --git a/.ruby-version b/.ruby-version
index aedc15b..57cf282 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-2.5.3
+2.6.5
diff --git a/.tool-versions b/.tool-versions
new file mode 100644
index 0000000..7811505
--- /dev/null
+++ b/.tool-versions
@@ -0,0 +1 @@
+ruby 2.6.5
diff --git a/Dockerfile b/Dockerfile
index ef33fc6..2bdc418 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM ruby:2.5-alpine
+FROM ruby:2.6.5-alpine
 
 RUN mkdir -p /usr/src/app
 WORKDIR /usr/src/app
diff --git a/spec/vrt/node_spec.rb b/spec/vrt/node_spec.rb
index 4ff5f46..7649687 100644
--- a/spec/vrt/node_spec.rb
+++ b/spec/vrt/node_spec.rb
@@ -78,9 +78,9 @@
 
     context 'cwe' do
       it 'has the exepected (concatenated) CWE IDs' do
-        expect(mappings[:cwe]).to eq [
-          'CWE-942',
-          'CWE-933'
+        expect(mappings[:cwe]).to eq %w[
+          CWE-942
+          CWE-933
         ]
       end
     end
diff --git a/vrt.gemspec b/vrt.gemspec
index de64ae4..c89102f 100644
--- a/vrt.gemspec
+++ b/vrt.gemspec
@@ -17,10 +17,9 @@ Gem::Specification.new do |spec|
   spec.require_paths = ['lib']
   spec.required_ruby_version = '>= 2.5'
 
-  spec.add_development_dependency 'bundler', '~> 1.14'
-  spec.add_development_dependency 'pry', '~> 0.11'
-  spec.add_development_dependency 'rake', '~> 12.3'
-  spec.add_development_dependency 'rspec', '~> 3.6'
-  # TODO: investigate why rubocop's jaro-winkler dependency fails to install in our alpine linux image
-  spec.add_development_dependency 'rubocop', '0.56.0'
+  spec.add_development_dependency 'bundler', '~> 2.1'
+  spec.add_development_dependency 'pry', '~> 0.12'
+  spec.add_development_dependency 'rake', '~> 13.0'
+  spec.add_development_dependency 'rspec', '~> 3.9'
+  spec.add_development_dependency 'rubocop', '~> 0.78'
 end