diff --git a/packages/lib/src/portal.ts b/packages/lib/src/portal.ts
index 050dbfac..28d85f39 100644
--- a/packages/lib/src/portal.ts
+++ b/packages/lib/src/portal.ts
@@ -18,7 +18,7 @@ class Portal extends Component<PortalProps> {
   }
 
   static isPortal(type: unknown): type is typeof Portal {
-    return !!type && typeof type === "function" && portalIdentifier in type
+    return typeof type === "function" && portalIdentifier in type
   }
 
   render(): JSX.Element {
diff --git a/packages/lib/src/signal.ts b/packages/lib/src/signal.ts
index f93ccca0..3d1cb5b6 100644
--- a/packages/lib/src/signal.ts
+++ b/packages/lib/src/signal.ts
@@ -42,7 +42,7 @@ export class Signal<T> {
   }
 
   static isSignal(x: any): x is Signal<any> {
-    return x && x[SignalKey]
+    return typeof x === "object" && !!x && SignalKey in x
   }
 
   static subscribeNode(node: Kaioken.VNode, signal: Signal<any>) {