diff --git a/.github/workflows/testing.yml b/.github/workflows/testing.yml
index a256e991..e0aecac7 100644
--- a/.github/workflows/testing.yml
+++ b/.github/workflows/testing.yml
@@ -14,6 +14,7 @@ jobs:
       fail-fast: true
       matrix:
         version:
+          - 20
           - 22
           - 24
     name: test and build package (node ${{ matrix.version }})
diff --git a/package-lock.json b/package-lock.json
index bf20849e..fc9a10b0 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -28,6 +28,9 @@
         "rimraf": "6.1.3",
         "ts-proto": "2.12.4",
         "typescript": "7.0.2"
+      },
+      "engines": {
+        "node": ">=20"
       }
     },
     "node_modules/@bufbuild/buf": {
diff --git a/package.json b/package.json
index 5a1f7ce4..aa77e46b 100644
--- a/package.json
+++ b/package.json
@@ -34,6 +34,9 @@
   "files": [
     "dist"
   ],
+  "engines": {
+    "node": ">=20"
+  },
   "devDependencies": {
     "@bufbuild/buf": "^1.18.0-1",
     "@tsconfig/node-lts": "^22.0.0",