diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9d4823e..56320cf 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -6,7 +6,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node-version: [18, 20]
+        node-version: [20]
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v3
@@ -27,7 +27,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node-version: [18, 20]
+        node-version: [20]
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v3
@@ -48,7 +48,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node-version: [18, 20]
+        node-version: [20]
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v3
@@ -74,7 +74,7 @@ jobs:
     runs-on: macos-latest
     strategy:
       matrix:
-        node-version: [18, 20]
+        node-version: [20]
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v3
diff --git a/.tool-versions b/.tool-versions
new file mode 100644
index 0000000..7bd5f0b
--- /dev/null
+++ b/.tool-versions
@@ -0,0 +1 @@
+nodejs 20.10.0