diff --git a/.github/workflows/ruby-tests.yml b/.github/workflows/ruby-tests.yml
index 2c05c80..42ec12f 100644
--- a/.github/workflows/ruby-tests.yml
+++ b/.github/workflows/ruby-tests.yml
@@ -14,10 +14,10 @@ jobs:
     strategy:
       matrix:
         ruby_version:
-          - 2.5
           - 2.6
           - 2.7
           - 3.0
+          - 3.1
     steps:
       - uses: actions/checkout@v2
       - name: Set up Ruby
diff --git a/.ruby-version b/.ruby-version
index 981a028..ef538c2 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-ruby-3
+3.1.2
diff --git a/Gemfile.lock b/Gemfile.lock
index eb5b8e0..0148fb4 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -124,4 +124,4 @@ DEPENDENCIES
   webrick (~> 1.7)
 
 BUNDLED WITH
-   2.2.4
+   2.3.11