diff --git a/.github/workflows/ruby.yml b/.github/workflows/ruby.yml
index 4946b56..4ad307c 100644
--- a/.github/workflows/ruby.yml
+++ b/.github/workflows/ruby.yml
@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        ruby-version: ['3.2'] # match with Dockerfile
+        ruby-version: ['3.3'] # match with Dockerfile
 
     steps:
     - uses: actions/checkout@v2
@@ -19,7 +19,7 @@ jobs:
     - name: Run test suite
       run: bundle exec rspec
     - name: Store coverage report
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v4
       with:
         name: code-coverage-report
         path: spec/coverage
diff --git a/Dockerfile b/Dockerfile
index 5361fcb..10f108e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,5 @@
 # match the Ruby version with GitHub Actions workflow:
-FROM ruby:3.2.0-slim
+FROM ruby:3.3.6-slim
 
 EXPOSE 25863
 
diff --git a/Gemfile b/Gemfile
index 34ed4d3..68d4349 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,10 +2,10 @@
 
 source 'https://rubygems.org'
 
-gem 'tty-box', '~> 0.7.0'
+gem 'tty-box'
 gem 'tty-prompt', git: 'https://github.com/seawolf/tty-prompt.git', branch: 'auto-select-only-option'
 gem 'tty-screen'
-gem 'zeitwerk', '~> 2.6'
+gem 'zeitwerk'
 
 group :development, :test do
   gem 'rspec'
diff --git a/Gemfile.lock b/Gemfile.lock
index 47adc35..2d373b1 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -12,61 +12,57 @@ GEM
   specs:
     ast (2.4.2)
     diff-lcs (1.5.1)
-    docile (1.4.0)
-    json (2.7.2)
+    docile (1.4.1)
+    json (2.9.1)
     language_server-protocol (3.17.0.3)
-    parallel (1.25.1)
-    parser (3.3.3.0)
+    parallel (1.26.3)
+    parser (3.3.6.0)
       ast (~> 2.4.1)
       racc
     pastel (0.8.0)
       tty-color (~> 0.5)
-    racc (1.8.0)
+    racc (1.8.1)
     rainbow (3.1.1)
-    regexp_parser (2.9.2)
-    rexml (3.3.1)
-      strscan
+    regexp_parser (2.9.3)
     rspec (3.13.0)
       rspec-core (~> 3.13.0)
       rspec-expectations (~> 3.13.0)
       rspec-mocks (~> 3.13.0)
-    rspec-core (3.13.0)
+    rspec-core (3.13.2)
       rspec-support (~> 3.13.0)
-    rspec-expectations (3.13.0)
+    rspec-expectations (3.13.3)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
-    rspec-mocks (3.13.0)
+    rspec-mocks (3.13.2)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
-    rspec-support (3.13.1)
-    rubocop (1.64.1)
+    rspec-support (3.13.2)
+    rubocop (1.69.2)
       json (~> 2.3)
       language_server-protocol (>= 3.17.0)
       parallel (~> 1.10)
       parser (>= 3.3.0.2)
       rainbow (>= 2.2.2, < 4.0)
-      regexp_parser (>= 1.8, < 3.0)
-      rexml (>= 3.2.5, < 4.0)
-      rubocop-ast (>= 1.31.1, < 2.0)
+      regexp_parser (>= 2.9.3, < 3.0)
+      rubocop-ast (>= 1.36.2, < 2.0)
       ruby-progressbar (~> 1.7)
-      unicode-display_width (>= 2.4.0, < 3.0)
-    rubocop-ast (1.31.3)
+      unicode-display_width (>= 2.4.0, < 4.0)
+    rubocop-ast (1.37.0)
       parser (>= 3.3.1.0)
-    rubocop-rspec (3.0.2)
+    rubocop-rspec (3.3.0)
       rubocop (~> 1.61)
     ruby-progressbar (1.13.0)
     simplecov (0.22.0)
       docile (~> 1.1)
       simplecov-html (~> 0.11)
       simplecov_json_formatter (~> 0.1)
-    simplecov-html (0.12.3)
+    simplecov-html (0.13.1)
     simplecov_json_formatter (0.1.4)
     strings (0.2.1)
       strings-ansi (~> 0.2)
       unicode-display_width (>= 1.5, < 3.0)
       unicode_utils (~> 1.4)
     strings-ansi (0.2.0)
-    strscan (3.1.0)
     tty-box (0.7.0)
       pastel (~> 0.8)
       strings (~> 0.2.0)
@@ -78,10 +74,10 @@ GEM
       tty-screen (~> 0.8)
       wisper (~> 2.0)
     tty-screen (0.8.2)
-    unicode-display_width (2.5.0)
+    unicode-display_width (2.6.0)
     unicode_utils (1.4.0)
     wisper (2.0.1)
-    zeitwerk (2.6.16)
+    zeitwerk (2.7.1)
 
 PLATFORMS
   ruby
@@ -92,10 +88,10 @@ DEPENDENCIES
   rubocop
   rubocop-rspec
   simplecov
-  tty-box (~> 0.7.0)
+  tty-box
   tty-prompt!
   tty-screen
-  zeitwerk (~> 2.6)
+  zeitwerk
 
 BUNDLED WITH
-   2.4.13
+   2.6.1