diff --git a/.github/workflows/ruby.yml b/.github/workflows/ruby.yml
index 7f73987..76e6fb1 100644
--- a/.github/workflows/ruby.yml
+++ b/.github/workflows/ruby.yml
@@ -7,7 +7,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby-version: ['2.7', '3.0']
+        ruby-version: ['2.7', '3.0', '3.1', '3.2']
         os: [ubuntu-latest]
 
     runs-on: ${{ matrix.os }}
diff --git a/Gemfile b/Gemfile
index 2028c84..e5c1de6 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,3 +6,5 @@ group :test do
     gem 'minitest'
     gem 'rake'
 end
+
+gem "matrix", "~> 0.4.2"