diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 9e5bff5..29e8898 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -15,6 +15,7 @@ jobs:
       matrix:
         ruby:
           - '3.4'
+          - '4.0'
 
     steps:
     - uses: actions/checkout@v3
diff --git a/Gemfile b/Gemfile
index 71a260b..abd565b 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,3 +6,6 @@ source "https://rubygems.org"
 gemspec
 
 gem "rake", "~> 13.0"
+gem "fiddle"
+gem "steep"
+gem "test-unit"
diff --git a/caotral.gemspec b/caotral.gemspec
index 6ddf92d..e513c45 100644
--- a/caotral.gemspec
+++ b/caotral.gemspec
@@ -26,9 +26,6 @@ Gem::Specification.new do |spec|
   spec.require_paths = ["lib"]
 
   # Uncomment to register a new dependency of your gem
-  spec.add_dependency "parser"
-  spec.add_development_dependency "test-unit"
-  spec.add_development_dependency "steep"
 
   # For more information and examples about making a new gem, check out our
   # guide at: https://bundler.io/guides/creating_gem.html