diff --git a/snap.manifest.json b/snap.manifest.json
index 8dd072c..d797cf0 100644
--- a/snap.manifest.json
+++ b/snap.manifest.json
@@ -3,7 +3,7 @@
   "description": "Nocturne Snap",
   "proposedName": "Nocturne Snap",
   "source": {
-    "shasum": "Y1d9pqTAXKjR2ReBb8ojP/teC2CGHsnaJHO3uhKMiiY=",
+    "shasum": "aRzafJIq0kfaFukKWqk804tgiHv81Kt6bLzI20QcQvs=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/src/index.ts b/src/index.ts
index 1e784b9..4c41812 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -52,8 +52,10 @@ const configThunk = thunk(async () => {
       return loadNocturneConfigBuiltin("mainnet");
     case 5:
       return loadNocturneConfigBuiltin("goerli");
-    default:
+    case 31_337:
       return loadNocturneConfigBuiltin("localhost");
+    default:
+      throw new Error(`ChainId ${chainId} not supported`);
   }
 });
 const kvStore = new SnapKvStore();