diff --git a/.github/shared/setup/action.yaml b/.github/shared/setup/action.yaml
index bc7ca11..fd348a2 100644
--- a/.github/shared/setup/action.yaml
+++ b/.github/shared/setup/action.yaml
@@ -1,11 +1,14 @@
-name: "setup ruby"
-description: "setup ruby"
-
+name: setup ruby
+description: setup ruby
+inputs:
+  working-directory:
+    description: directory to use
+    required: true
 runs:
-  using: "composite"
+  using: composite
   steps:
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
         bundler-cache: true
-        working-directory: ./2024/ruby
+        working-directory: ${{ inputs.working-directory }}
diff --git a/.github/workflows/2021-ruby.yaml b/.github/workflows/2021-ruby.yaml
index 9231707..526f05b 100644
--- a/.github/workflows/2021-ruby.yaml
+++ b/.github/workflows/2021-ruby.yaml
@@ -12,20 +12,25 @@ defaults:
     working-directory: ./2021/ruby
 
 jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: debug
+        run: pwd
+      - name: Setup Ruby
+        uses: ./.github/shared/setup
+        with:
+          working-directory: ./2021/ruby
+      - name: Run rubocop
+        run: bundle exec rubocop
   tests:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
-    - name: Determine ruby version
-      id: determine-ruby-version
-      run: |
-        VERSION=$(cat .ruby-version)
-        echo "VERSION=${VERSION}" >> "$GITHUB_OUTPUT"
-    - name: Set up Ruby
-      uses: ruby/setup-ruby@v1
-      with:
-        ruby-version: ${{ steps.determine-ruby-version.outputs.VERSION }}
-        bundler-cache: true
-        working-directory: ./2021/ruby
-    - name: Run tests
-      run: bundle exec rspec
+      - uses: actions/checkout@v3
+      - name: Setup Ruby
+        uses: ./.github/shared/setup
+        with:
+          working-directory: ./2021/ruby
+      - name: Run tests
+        run: bundle exec rspec
diff --git a/.github/workflows/2024-ruby.yaml b/.github/workflows/2024-ruby.yaml
index 72ae51d..bd1a36c 100644
--- a/.github/workflows/2024-ruby.yaml
+++ b/.github/workflows/2024-ruby.yaml
@@ -17,6 +17,8 @@ jobs:
       - uses: actions/checkout@v3
       - name: Setup Ruby
         uses: ./.github/shared/setup
+        with:
+          working-directory: ./2024/ruby
       - name: Run rubocop
         run: bundle exec rubocop
   tests:
@@ -25,5 +27,7 @@ jobs:
       - uses: actions/checkout@v3
       - name: Setup Ruby
         uses: ./.github/shared/setup
+        with:
+          working-directory: ./2024/ruby
       - name: Run tests
         run: bundle exec rspec
diff --git a/2021/ruby/.rubocop.yml b/2021/ruby/.rubocop.yml
index a44bea2..6accd83 100644
--- a/2021/ruby/.rubocop.yml
+++ b/2021/ruby/.rubocop.yml
@@ -1,3 +1,7 @@
+require:
+  - rubocop-rspec
+  - rubocop-rake
+
 AllCops:
   Exclude:
     - bin/**/*
@@ -8,7 +12,8 @@ Style/Documentation:
 Style/FrozenStringLiteralComment:
   Enabled: false
 Style/StringLiterals:
-  Enabled: false
+  Enabled: true
+  EnforcedStyle: double_quotes
 Style/TrailingCommaInHashLiteral:
   Enabled: false
 Style/NumericPredicate:
@@ -16,5 +21,9 @@ Style/NumericPredicate:
 Metrics/BlockLength:
   Exclude:
     - spec/**/*
+RSpec/ExampleLength:
+  Max: 20
+RSpec/MultipleExpectations:
+  Enabled: false
 
 inherit_from: .rubocop_todo.yml
diff --git a/2021/ruby/.rubocop_todo.yml b/2021/ruby/.rubocop_todo.yml
new file mode 100644
index 0000000..dfb999f
--- /dev/null
+++ b/2021/ruby/.rubocop_todo.yml
@@ -0,0 +1,19 @@
+# This configuration was generated by
+# `rubocop --auto-gen-config`
+# on 2024-12-16 16:59:11 UTC using RuboCop version 1.69.2.
+# 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
+# versions of RuboCop, may require this file to be generated again.
+
+# Offense count: 1
+RSpec/MultipleDescribes:
+  Exclude:
+    - 'spec/advent_02_spec.rb'
+
+# Offense count: 1
+# This cop supports safe autocorrection (--autocorrect).
+# Configuration parameters: AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, AllowedPatterns, SplitStrings.
+# URISchemes: http, https
+Layout/LineLength:
+  Max: 122
diff --git a/2021/ruby/.ruby-version b/2021/ruby/.ruby-version
index d9c62ed..9c25013 100644
--- a/2021/ruby/.ruby-version
+++ b/2021/ruby/.ruby-version
@@ -1 +1 @@
-3.0.2
\ No newline at end of file
+3.3.6
diff --git a/2021/ruby/Gemfile b/2021/ruby/Gemfile
index 4269dc0..1e39f42 100644
--- a/2021/ruby/Gemfile
+++ b/2021/ruby/Gemfile
@@ -1,10 +1,12 @@
 # frozen_string_literal: true
 
-source 'https://rubygems.org'
+source "https://rubygems.org"
 
-ruby File.open('.ruby-version', 'rb') { |f| f.read.chomp }
+ruby File.open(".ruby-version", "rb") { |f| f.read.chomp }
 
-gem 'awesome_print'
-gem 'pry', '~> 0.12.0'
-gem 'rspec', '~> 3.8.0'
-gem 'rubocop', '~> 0.60'
+gem "awesome_print"
+gem "pry", "~> 0.12.0"
+gem "rspec", "~> 3.8.0"
+gem "rubocop", "~> 1.69.2"
+gem "rubocop-rake", "~> 0.6.0"
+gem "rubocop-rspec", "~> 3.2.0"
diff --git a/2021/ruby/Gemfile.lock b/2021/ruby/Gemfile.lock
index 29ef029..470614b 100644
--- a/2021/ruby/Gemfile.lock
+++ b/2021/ruby/Gemfile.lock
@@ -4,17 +4,20 @@ GEM
     ast (2.4.2)
     awesome_print (1.9.2)
     coderay (1.1.3)
-    diff-lcs (1.4.4)
+    diff-lcs (1.5.1)
+    json (2.9.0)
+    language_server-protocol (3.17.0.3)
     method_source (0.9.2)
-    parallel (1.21.0)
-    parser (3.0.3.1)
+    parallel (1.26.3)
+    parser (3.3.6.0)
       ast (~> 2.4.1)
+      racc
     pry (0.12.2)
       coderay (~> 1.1.0)
       method_source (~> 0.9.0)
-    rainbow (3.0.0)
-    regexp_parser (2.1.1)
-    rexml (3.2.5)
+    racc (1.8.1)
+    rainbow (3.1.1)
+    regexp_parser (2.9.3)
     rspec (3.8.0)
       rspec-core (~> 3.8.0)
       rspec-expectations (~> 3.8.0)
@@ -28,31 +31,41 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.8.0)
     rspec-support (3.8.3)
-    rubocop (0.93.1)
+    rubocop (1.69.2)
+      json (~> 2.3)
+      language_server-protocol (>= 3.17.0)
       parallel (~> 1.10)
-      parser (>= 2.7.1.5)
+      parser (>= 3.3.0.2)
       rainbow (>= 2.2.2, < 4.0)
-      regexp_parser (>= 1.8)
-      rexml
-      rubocop-ast (>= 0.6.0)
+      regexp_parser (>= 2.9.3, < 3.0)
+      rubocop-ast (>= 1.36.2, < 2.0)
       ruby-progressbar (~> 1.7)
-      unicode-display_width (>= 1.4.0, < 2.0)
-    rubocop-ast (1.14.0)
-      parser (>= 3.0.1.1)
-    ruby-progressbar (1.11.0)
-    unicode-display_width (1.8.0)
+      unicode-display_width (>= 2.4.0, < 4.0)
+    rubocop-ast (1.37.0)
+      parser (>= 3.3.1.0)
+    rubocop-rake (0.6.0)
+      rubocop (~> 1.0)
+    rubocop-rspec (3.2.0)
+      rubocop (~> 1.61)
+    ruby-progressbar (1.13.0)
+    unicode-display_width (3.1.2)
+      unicode-emoji (~> 4.0, >= 4.0.4)
+    unicode-emoji (4.0.4)
 
 PLATFORMS
+  arm64-darwin-24
   x86_64-linux
 
 DEPENDENCIES
   awesome_print
   pry (~> 0.12.0)
   rspec (~> 3.8.0)
-  rubocop (~> 0.60)
+  rubocop (~> 1.69.2)
+  rubocop-rake (~> 0.6.0)
+  rubocop-rspec (~> 3.2.0)
 
 RUBY VERSION
-   ruby 3.0.2p107
+   ruby 3.3.6p108
 
 BUNDLED WITH
    2.2.22
diff --git a/2021/ruby/lib/advent_02.rb b/2021/ruby/lib/advent_02.rb
index dd55aa4..72f2a9e 100644
--- a/2021/ruby/lib/advent_02.rb
+++ b/2021/ruby/lib/advent_02.rb
@@ -1,4 +1,3 @@
-
 class DepthCalculator
   def initialize(data)
     @data = data
@@ -8,18 +7,18 @@ def initialize(data)
 
   def process_action(action, amount)
     case action
-    when 'forward'
+    when "forward"
       @horizontal_position += amount
-    when 'down'
+    when "down"
       @depth += amount
-    when 'up'
+    when "up"
       @depth -= amount
     end
   end
 
   def process
     @data.each do |line|
-      action, amount = line.split(' ')
+      action, amount = line.split(" ")
       amount = amount.to_i
       process_action(action, amount)
     end
@@ -30,7 +29,6 @@ def product
   end
 end
 
-
 class AimCalculator
   def initialize(data)
     @data = data
@@ -41,19 +39,19 @@ def initialize(data)
 
   def process_action(action, amount)
     case action
-    when 'forward'
+    when "forward"
       @horizontal_position += amount
       @depth += (@aim * amount)
-    when 'down'
+    when "down"
       @aim += amount
-    when 'up'
+    when "up"
       @aim -= amount
     end
   end
 
   def process
     @data.each do |line|
-      action, amount = line.split(' ')
+      action, amount = line.split(" ")
       amount = amount.to_i
       process_action(action, amount)
     end
diff --git a/2021/ruby/lib/advent_03.rb b/2021/ruby/lib/advent_03.rb
index e9c067e..f806a5f 100644
--- a/2021/ruby/lib/advent_03.rb
+++ b/2021/ruby/lib/advent_03.rb
@@ -31,27 +31,27 @@ def least_common_bit(data, index)
 
   def episolon_rate
     result = (0...@word_length).map { |index| least_common_bit(@data, index) }
-    result.join('').to_i(2)
+    result.join("").to_i(2)
   end
 
   def gamma_rate
     result = (0...@word_length).map { |index| most_common_bit(@data, index) }
-    result.join('').to_i(2)
+    result.join("").to_i(2)
   end
 
   def power_consumption
     episolon_rate * gamma_rate
   end
 
-  def determine_rating(data, use_most_common_bit = true, index = 0)
-    return 0 if data.length.zero?
+  def determine_rating(data, use_most_common_bit: true, index: 0)
+    return 0 if data.empty?
     return data[0].to_i(2) if data.length == 1
 
     bit = use_most_common_bit ? most_common_bit(data, index) : least_common_bit(data, index)
     data.select! { |e| e[index] == bit.to_s }
     index += 1
 
-    determine_rating(data, use_most_common_bit, index)
+    determine_rating(data, use_most_common_bit: use_most_common_bit, index: index)
   end
 
   def oxygen_generator_rating
@@ -61,7 +61,7 @@ def oxygen_generator_rating
 
   def co2_scubber_rating
     to_process = @data.map(&:clone)
-    determine_rating(to_process, false)
+    determine_rating(to_process, use_most_common_bit: false)
   end
 
   def life_support_rating
diff --git a/2021/ruby/spec/advent_01_spec.rb b/2021/ruby/spec/advent_01_spec.rb
index f209307..6339313 100644
--- a/2021/ruby/spec/advent_01_spec.rb
+++ b/2021/ruby/spec/advent_01_spec.rb
@@ -1,17 +1,17 @@
-require 'spec_helper'
-require 'advent_01'
+require "spec_helper"
+require "advent_01"
 
-describe 'DepthCounter' do
+describe "DepthCounter" do
   let(:puzzle_input) do
-    File.readlines('./spec/fixtures/advent-01.txt').map(&:to_i)
+    File.readlines("./spec/fixtures/advent-01.txt").map(&:to_i)
   end
 
-  it 'counts the number of increased measurements' do
+  it "counts the number of increased measurements" do
     count = DepthCounter.new(puzzle_input).total_increments
     expect(count).to be(1754)
   end
 
-  it 'counts using window measurement' do
+  it "counts using window measurement" do
     count = DepthCounter.new(puzzle_input).total_window_measurement_increments
 
     expect(count).to be(1789)
diff --git a/2021/ruby/spec/advent_02_spec.rb b/2021/ruby/spec/advent_02_spec.rb
index fd9339e..97c206a 100644
--- a/2021/ruby/spec/advent_02_spec.rb
+++ b/2021/ruby/spec/advent_02_spec.rb
@@ -1,12 +1,12 @@
-require 'spec_helper'
-require 'advent_02'
+require "spec_helper"
+require "advent_02"
 
-describe 'DepthCalculator' do
+describe "DepthCalculator" do
   let(:puzzle_input) do
-    File.readlines('./spec/fixtures/advent-02.txt')
+    File.readlines("./spec/fixtures/advent-02.txt")
   end
 
-  it 'calculates the product' do
+  it "calculates the product" do
     dc = DepthCalculator.new(puzzle_input)
     dc.process
 
@@ -14,19 +14,19 @@
   end
 end
 
-describe 'AimCalculator' do
+describe "AimCalculator" do
   let(:puzzle_input) do
-    File.readlines('./spec/fixtures/advent-02.txt')
+    File.readlines("./spec/fixtures/advent-02.txt")
   end
 
-  it 'calculates the product from sample' do
+  it "calculates the product from sample" do
     sample_input = [
-      'forward 5',
-      'down 5',
-      'forward 8',
-      'up 3',
-      'down 8',
-      'forward 2',
+      "forward 5",
+      "down 5",
+      "forward 8",
+      "up 3",
+      "down 8",
+      "forward 2"
     ]
 
     dc = AimCalculator.new(sample_input)
@@ -35,7 +35,7 @@
     expect(dc.product).to be(900)
   end
 
-  it 'calculates the product' do
+  it "calculates the product" do
     dc = AimCalculator.new(puzzle_input)
     dc.process
 
diff --git a/2021/ruby/spec/advent_03_spec.rb b/2021/ruby/spec/advent_03_spec.rb
index 4ceb551..f9a27db 100644
--- a/2021/ruby/spec/advent_03_spec.rb
+++ b/2021/ruby/spec/advent_03_spec.rb
@@ -1,25 +1,15 @@
-require 'spec_helper'
-require 'advent_03'
+require "spec_helper"
+require "advent_03"
 
-describe 'BinaryDiagnostic' do
+describe "BinaryDiagnostic" do
   let(:puzzle_input) do
-    File.readlines('./spec/fixtures/advent-03.txt').map(&:chomp)
+    File.readlines("./spec/fixtures/advent-03.txt").map(&:chomp)
   end
 
-  it 'calculates the sample power consumption' do
+  it "calculates the sample power consumption" do
     sample_input = %w[
-      00100
-      11110
-      10110
-      10111
-      10101
-      01111
-      00111
-      11100
-      10000
-      11001
-      00010
-      01010
+      00100 11110 10110 10111 10101 01111 00111 11100 10000 11001
+      00010 01010
     ]
 
     dc = BinaryDiagnostic.new(sample_input)
@@ -34,13 +24,13 @@
     expect(dc.life_support_rating).to be(230)
   end
 
-  it 'calculates the power consumption' do
+  it "calculates the power consumption" do
     dc = BinaryDiagnostic.new(puzzle_input)
 
     expect(dc.power_consumption).to be(388_256_4)
   end
 
-  it 'calculates life support rating' do
+  it "calculates life support rating" do
     dc = BinaryDiagnostic.new(puzzle_input)
 
     expect(dc.life_support_rating).to be(338_517_0)