diff --git a/djx/src/main/ts/tsx/traits.ts b/djx/src/main/ts/tsx/traits.ts
--- a/djx/src/main/ts/tsx/traits.ts
+++ b/djx/src/main/ts/tsx/traits.ts
@@ -27,7 +27,7 @@ export interface IRecursivelyDestroyable
     destroyRecursive(): void;
 }
 
-export const isNode = (el: unknown): el is Node => !!(el && (el as Node).nodeName && (el as Node).nodeType);
+export const isNode = (el: unknown): el is Node => !!(el !== null  && typeof el === "object" && (el as Node).nodeName && (el as Node).nodeType);
 
 export const isElementNode = (el: unknown): el is Element => isNode(el) && el.nodeType === 1;
 
@@ -43,9 +43,9 @@ export const isDocumentTypeNode = (el: u
 
 export const isDocumentFragmentNode = (el: unknown): el is DocumentFragment => isNode(el) && el.nodeType === 11;
 
-export const isWidget = (v: unknown): v is _WidgetBase => !!(v && "domNode" in (v as _WidgetBase));
+export const isWidget = (v: unknown): v is _WidgetBase => !!(v !== null && typeof v === "object" && "domNode" in (v as _WidgetBase));
 
-export const isRendition = (v: unknown): v is Rendition => !!(v && typeof (v as Rendition).getDomNode === "function");
+export const isRendition = (v: unknown): v is Rendition => !!(v !== null && typeof v === "object" && typeof (v as Rendition).getDomNode === "function");
 
 /**
  * @deprecated use isRendition