diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 00b888b8..f58bfe7c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -19,7 +19,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: ['3.0', 3.1, 3.2, ruby-head, jruby]
+        ruby: ['3.0', 3.1, 3.2, 3.3, ruby-head, jruby]
     steps:
       - name: Clone repository
         uses: actions/checkout@v3
diff --git a/sparql.gemspec b/sparql.gemspec
index d96bdb43..a6eb98b9 100755
--- a/sparql.gemspec
+++ b/sparql.gemspec
@@ -38,6 +38,7 @@ Gem::Specification.new do |gem|
   gem.add_runtime_dependency     'sparql-client',      '~> 3.3'
   gem.add_runtime_dependency     'rdf-xsd',            '~> 3.3'
 
+  gem.add_development_dependency 'getoptlong',         '~> 0.2'
   gem.add_development_dependency 'sinatra',            '~> 3.1'
   gem.add_development_dependency 'rack',               '>= 2.2', '< 4'
   gem.add_development_dependency 'rack-test',          '~> 2.1'