diff --git a/.github/workflows/release-on-pr-merge.yml b/.github/workflows/release-on-pr-merge.yml
index a25550d..2c0913b 100644
--- a/.github/workflows/release-on-pr-merge.yml
+++ b/.github/workflows/release-on-pr-merge.yml
@@ -14,9 +14,6 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Ruby
         uses: ruby/setup-ruby@v1
-        with:
-          ruby-version: 3.3
-
       - name: Setup git
         run: |
           git config --global user.name "$(git --no-pager log --format=format:'%an' -n 1)"
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 9d7c032..b778b3c 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -14,7 +14,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest]
-        ruby_version: ['3.1', '3.2', '3.3']
+        ruby_version: ['3.1', '3.2', '3.3', '3.4']
       fail-fast: false
 
     steps:
@@ -42,7 +42,7 @@ jobs:
     strategy:
       matrix:
         os: [windows-latest, ubuntu-latest]
-        ruby_version: ['3.1', '3.2', '3.3']
+        ruby_version: ['3.1', '3.2', '3.3', '3.4']
       fail-fast: false
 
     steps:
@@ -111,7 +111,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest]
-        ruby_version: ['3.1', '3.2', '3.3']
+        ruby_version: ['3.1', '3.2', '3.3', '3.4']
       fail-fast: false
 
     steps:
diff --git a/.ruby-version b/.ruby-version
deleted file mode 100644
index 2a819a6..0000000
--- a/.ruby-version
+++ /dev/null
@@ -1 +0,0 @@
-3.3
diff --git a/.tool-versions b/.tool-versions
new file mode 100644
index 0000000..380cf51
--- /dev/null
+++ b/.tool-versions
@@ -0,0 +1 @@
+ruby 3.4