diff --git a/default.json b/default.json
index 9e875b9..f52e052 100644
--- a/default.json
+++ b/default.json
@@ -140,6 +140,19 @@
         "gate:renovate-major"
       ]
     },
+    {
+      "description": "Label Node runtime major updates (node-version in workflows, .nvmrc, engines) for the Eir agent-gate (tier 3): Node 25+ dropped corepack and the fleet pins one Node major per repo, so a runtime major is never a blind merge",
+      "matchDatasources": [
+        "node-version"
+      ],
+      "matchUpdateTypes": [
+        "major"
+      ],
+      "automerge": false,
+      "addLabels": [
+        "gate:renovate-major"
+      ]
+    },
     {
       "description": "Label docker-compose major image updates for the Eir agent-gate (tier 3)",
       "matchManagers": [
diff --git a/renovate.json b/renovate.json
index 2094c1f..293a5c8 100644
--- a/renovate.json
+++ b/renovate.json
@@ -140,6 +140,19 @@
         "gate:renovate-major"
       ]
     },
+    {
+      "description": "Label Node runtime major updates (node-version in workflows, .nvmrc, engines) for the Eir agent-gate (tier 3): Node 25+ dropped corepack and the fleet pins one Node major per repo, so a runtime major is never a blind merge",
+      "matchDatasources": [
+        "node-version"
+      ],
+      "matchUpdateTypes": [
+        "major"
+      ],
+      "automerge": false,
+      "addLabels": [
+        "gate:renovate-major"
+      ]
+    },
     {
       "description": "Label docker-compose major image updates for the Eir agent-gate (tier 3)",
       "matchManagers": [