diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 9f1758c..acef15d 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -1,25 +1,6 @@
 name: CI
 on: [push, pull_request, workflow_dispatch]
 jobs:
-  puppet-3-8-7:
-    env:
-      PUPPET_VERSIONS: "3.8.7"
-      PUPPET_VERSION: "3.8.7"
-      RUBOCOP_TEST: false
-      RSPEC_TEST: true
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        ruby-version: ["2.0", "2.1"]
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v1
-      - name: Build container
-        run: docker build . --file Dockerfile --tag octocatalog-diff:ruby${{matrix.ruby-version}} --build-arg RUBY_VERSION=${{matrix.ruby-version}}
-      - name: Tests
-        run: docker run -e PUPPET_VERSION -e PUPPET_VERSIONS -e RSPEC_TEST -e RUBOCOP_TEST -e ENFORCE_COVERAGE octocatalog-diff:ruby${{matrix.ruby-version}} /app/script/cibuild
-
   puppet-4-10-10:
     env:
       PUPPET_VERSIONS: "4.10.10"
@@ -30,7 +11,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby-version: ["2.1", "2.2", "2.3"]
+        ruby-version: ["2.5", "2.6"]
     steps:
       - name: Checkout code
         uses: actions/checkout@v1
@@ -39,22 +20,22 @@ jobs:
       - name: Tests
         run: docker run -e PUPPET_VERSION -e PUPPET_VERSIONS -e RSPEC_TEST -e RUBOCOP_TEST -e ENFORCE_COVERAGE octocatalog-diff:ruby${{matrix.ruby-version}} /app/script/cibuild
 
-  puppet-5-5-8:
+  puppet-5-5-22:
     env:
-      PUPPET_VERSIONS: "5.5.8"
-      PUPPET_VERSION: "5.5.8"
+      PUPPET_VERSIONS: "5.5.22"
+      PUPPET_VERSION: "5.5.22"
       RUBOCOP_TEST: false
       RSPEC_TEST: true
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
-        ruby-version: ["2.4", "2.5", "2.6"]
+        ruby-version: ["2.5", "2.6"]
     steps:
       - name: Checkout code
         uses: actions/checkout@v1
       - name: Build container
-        run: docker build . --file Dockerfile --tag octocatalog-diff:ruby${{matrix.ruby-version}} --build-arg RUBY_VERSION=${{matrix.ruby-version}}-stretch
+        run: docker build . --file Dockerfile --tag octocatalog-diff:ruby${{matrix.ruby-version}} --build-arg RUBY_VERSION=${{matrix.ruby-version}}-buster
       - name: Tests
         run: docker run -e PUPPET_VERSION -e PUPPET_VERSIONS -e RSPEC_TEST -e RUBOCOP_TEST -e ENFORCE_COVERAGE octocatalog-diff:ruby${{matrix.ruby-version}} /app/script/cibuild
 
@@ -73,7 +54,7 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v1
       - name: Build container
-        run: docker build . --file Dockerfile --tag octocatalog-diff:ruby${{matrix.ruby-version}} --build-arg RUBY_VERSION=${{matrix.ruby-version}}-stretch
+        run: docker build . --file Dockerfile --tag octocatalog-diff:ruby${{matrix.ruby-version}} --build-arg RUBY_VERSION=${{matrix.ruby-version}}-buster
       - name: Tests
         run: docker run -e PUPPET_VERSION -e PUPPET_VERSIONS -e RSPEC_TEST -e RUBOCOP_TEST -e ENFORCE_COVERAGE octocatalog-diff:ruby${{matrix.ruby-version}} /app/script/cibuild
       - name: Rubocop and Coverage
diff --git a/.rubocop.yml b/.rubocop.yml
index 48f25aa..b606d74 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -57,6 +57,8 @@ Style/Documentation:
   Enabled: false
 
 # To fix later
+Style/FormatStringToken:
+  Enabled: false
 Style/PercentLiteralDelimiters:
   Enabled: false
 Style/VariableNumber:
@@ -73,7 +75,13 @@ Style/EmptyMethod:
   Enabled: false
 Style/SymbolArray:
   Enabled: false
-Style/IndentHeredoc:
+Style/YodaCondition:
   Enabled: false
-Style/ExtraSpacing:
+Layout/HeredocIndentation:
+  Enabled: false
+Layout/ExtraSpacing:
+  Enabled: false
+Performance/Caller:
+  Enabled: false
+Style/WordArray:
   Enabled: false
diff --git a/Gemfile b/Gemfile
index 76de7e7..25df42a 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,5 +2,6 @@ source 'https://rubygems.org'
 
 gem 'rake', '12.3.3'
 gem 'httparty', '0.16.3'
+gem 'rubocop', '0.49.0'
 
 gemspec
diff --git a/lib/octocatalog-diff/api/v1/override.rb b/lib/octocatalog-diff/api/v1/override.rb
index b6d56c2..8624c77 100644
--- a/lib/octocatalog-diff/api/v1/override.rb
+++ b/lib/octocatalog-diff/api/v1/override.rb
@@ -74,7 +74,7 @@ module OctocatalogDiff
           return value if datatype == 'string'
           return parse_json(value) if datatype == 'json'
           return nil if datatype == 'nil'
-          if datatype == 'fixnum' || datatype == 'integer'
+          if ['fixnum', 'integer'].include? datatype
             return Regexp.last_match(1).to_i if value =~ /^(-?\d+)$/
             raise ArgumentError, "Illegal integer '#{value}'"
           end
diff --git a/lib/octocatalog-diff/catalog-diff/differ.rb b/lib/octocatalog-diff/catalog-diff/differ.rb
index 37828b9..3d959fa 100644
--- a/lib/octocatalog-diff/catalog-diff/differ.rb
+++ b/lib/octocatalog-diff/catalog-diff/differ.rb
@@ -262,7 +262,7 @@ module OctocatalogDiff
           # Process each attribute in the resource
           resource.each do |k, v|
             # Title was pre-processed
-            next if k == 'title' || k == 'type'
+            next if ['title', 'type'].include? k
 
             # Handle parameters
             if k == 'parameters'
@@ -272,7 +272,7 @@ module OctocatalogDiff
               # The order of tags is unimportant. Sort this array to avoid false diffs if order changes.
               # Also if tags is empty, don't add.
               hsh[k] = v.sort if v.is_a?(Array) && v.any?
-            elsif k == 'file' || k == 'line'
+            elsif ['file', 'line'].include? k
               # We don't care, for the purposes of catalog-diff, from which manifest and line this resource originated.
               # However, we may report this to the user, so we will keep it in here for now.
               hsh[k] = v
@@ -354,7 +354,7 @@ module OctocatalogDiff
           elsif operator == '=->'
             # String equality test only of the old value
             matcher = ->(x, _y) { x == value }
-          elsif operator == '=~>' || operator == '=&>'
+          elsif ['=~>', '=&>'].include? operator
             begin
               my_regex = Regexp.new(value, Regexp::IGNORECASE)
             rescue RegexpError => exc
diff --git a/lib/octocatalog-diff/cli/options.rb b/lib/octocatalog-diff/cli/options.rb
index 155839e..e295642 100644
--- a/lib/octocatalog-diff/cli/options.rb
+++ b/lib/octocatalog-diff/cli/options.rb
@@ -99,7 +99,7 @@ module OctocatalogDiff
       # option will populate any of the 'to' and 'from' variants that are missing.
       # @param :datatype [?] Expected data type
       def self.option_globally_or_per_branch(opts = {})
-        opts[:filename] = caller[0].split(':').first
+        opts[:filename] = opts[:filename] = caller[0].split(':').first
         datatype = opts.fetch(:datatype, '')
         return option_globally_or_per_branch_string(opts) if datatype.is_a?(String)
         return option_globally_or_per_branch_array(opts) if datatype.is_a?(Array)
diff --git a/lib/octocatalog-diff/cli/options/compare_file_text.rb b/lib/octocatalog-diff/cli/options/compare_file_text.rb
index a5b465b..b189209 100644
--- a/lib/octocatalog-diff/cli/options/compare_file_text.rb
+++ b/lib/octocatalog-diff/cli/options/compare_file_text.rb
@@ -23,7 +23,7 @@ OctocatalogDiff::Cli::Options::Option.newoption(:compare_file_text) do
     parser.on('--[no-]compare-file-text[=force]', 'Compare text, not source location, of file resources') do |x|
       if x == 'force'
         options[:compare_file_text] = :force
-      elsif x == true || x == false
+      elsif [true, false].include? x
         options[:compare_file_text] = x
       else
         raise OptionParser::NeedlessArgument("needless argument: --compare-file-text=#{x}")
diff --git a/octocatalog-diff.gemspec b/octocatalog-diff.gemspec
index 118b9e2..4315fb7 100644
--- a/octocatalog-diff.gemspec
+++ b/octocatalog-diff.gemspec
@@ -18,10 +18,10 @@ Gem::Specification.new do |s|
   s.homepage    = 'https://github.com/github/octocatalog-diff'
   s.summary     = 'Compile Puppet catalogs from 2 branches, versions, etc., and compare them.'
   s.description = <<-EOF
-Octocatalog-Diff assists with Puppet development and testing by enabling the user to
-compile 2 Puppet catalogs and compare them. It is possible to compare different
-branches, different versions, and different fact values. This is intended to be run
-from a local development environment or in CI.
+  Octocatalog-Diff assists with Puppet development and testing by enabling the user to
+  compile 2 Puppet catalogs and compare them. It is possible to compare different
+  branches, different versions, and different fact values. This is intended to be run
+  from a local development environment or in CI.
 EOF
 
   s.add_runtime_dependency 'diffy', '>= 3.1.0'
@@ -31,11 +31,11 @@ EOF
   s.add_runtime_dependency 'rugged', '>= 0.25.0b2'
 
   s.add_development_dependency 'rspec', '~> 3.4.0'
-  s.add_development_dependency 'rake', '12.3.1'
+  s.add_development_dependency 'rake', '12.3.3'
   s.add_development_dependency 'parallel_tests', '2.7.1'
   s.add_development_dependency 'rspec-retry', '0.5.0'
 
-  s.add_development_dependency 'rubocop', '= 0.48.1'
+  s.add_development_dependency 'rubocop', '= 0.49.0'
 
   s.add_development_dependency 'simplecov', '~> 0.14.1'
   s.add_development_dependency 'simplecov-erb', '~> 0.1.1'
diff --git a/spec/octocatalog-diff/tests/catalog-util/fileresources_spec.rb b/spec/octocatalog-diff/tests/catalog-util/fileresources_spec.rb
index 10d3789..77c02a6 100644
--- a/spec/octocatalog-diff/tests/catalog-util/fileresources_spec.rb
+++ b/spec/octocatalog-diff/tests/catalog-util/fileresources_spec.rb
@@ -92,10 +92,10 @@ describe OctocatalogDiff::CatalogUtil::FileResources do
     it 'should expand globs in modulepath, if present' do
       allow(File).to receive(:file?).with('/a/environment.conf').and_return(true)
       allow(File).to receive(:read).with('/a/environment.conf')
-        .and_return('modulepath=modules:extra_mods/*/modules:$basemoduledir')
+                                   .and_return('modulepath=modules:extra_mods/*/modules:$basemoduledir')
       allow(Dir).to receive(:glob).with('/a/modules').and_return(['/a/modules'])
       allow(Dir).to receive(:glob).with('/a/extra_mods/*/modules')
-        .and_return(['/a/extra_mods/a/modules', '/a/extra_mods/b/modules'])
+                                  .and_return(['/a/extra_mods/a/modules', '/a/extra_mods/b/modules'])
       result = OctocatalogDiff::CatalogUtil::FileResources.module_path('/a')
       expect(result).to eq(['/a/modules', '/a/extra_mods/a/modules', '/a/extra_mods/b/modules'])
     end
diff --git a/spec/octocatalog-diff/tests/catalog-util/git_spec.rb b/spec/octocatalog-diff/tests/catalog-util/git_spec.rb
index 4f01fc9..2ca7575 100644
--- a/spec/octocatalog-diff/tests/catalog-util/git_spec.rb
+++ b/spec/octocatalog-diff/tests/catalog-util/git_spec.rb
@@ -96,7 +96,9 @@ describe OctocatalogDiff::CatalogUtil::Git do
       it 'should return the sha from rugged' do
         opts = { branch: 'foo', basedir: '/tmp/bar' }
         expect(Rugged::Repository).to receive(:new).with('/tmp/bar')
-          .and_return(OpenStruct.new(branches: { 'foo' => OpenStruct.new(target_id: 'abcdef012345') }))
+                                                   .and_return(OpenStruct.new(branches: {
+                                                                                'foo' => OpenStruct.new(target_id: 'abcdef012345')
+                                                                              }))
         result = described_class.branch_sha(opts)
         expect(result).to eq('abcdef012345')
       end
diff --git a/vendor/cache/mime-types-3.5.2.gem b/vendor/cache/mime-types-3.5.2.gem
new file mode 100644
index 0000000..57a6ae2
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diff --git a/vendor/cache/mime-types-data-3.2023.1205.gem b/vendor/cache/mime-types-data-3.2023.1205.gem
new file mode 100644
index 0000000..dbe83e6
Binary files /dev/null and b/vendor/cache/mime-types-data-3.2023.1205.gem differ
diff --git a/vendor/cache/rubocop-0.49.0.gem b/vendor/cache/rubocop-0.49.0.gem
new file mode 100644
index 0000000..ad7fa4c
Binary files /dev/null and b/vendor/cache/rubocop-0.49.0.gem differ