diff --git a/lib/layer/decorate.mjs b/lib/layer/decorate.mjs
index 6d79a10d4..a52c589ee 100644
--- a/lib/layer/decorate.mjs
+++ b/lib/layer/decorate.mjs
@@ -25,7 +25,7 @@ The layer object to be decorated.
 export default async function decorate(layer) {
 
   // Decorate layer format methods.
-  await mapp.layer.formats[layer.format](layer);
+  await mapp.layer.formats[layer.format]?.(layer);
 
   // If layer does not exist, return.
   if (!layer.L) return;