diff --git a/src/serve_rendered.js b/src/serve_rendered.js
index ff8a023..662549e 100644
--- a/src/serve_rendered.js
+++ b/src/serve_rendered.js
@@ -780,8 +780,9 @@ export const serve_rendered = {
             image.resize(width * scale, height * scale);
           }
 
+          var composite_array = [];
           if (opt_overlay) {
-            image.composite([{ input: opt_overlay }]);
+            composite_array.push({ input: opt_overlay });
           }
           if (item.watermark) {
             const canvas = createCanvas(scale * width, scale * height);
@@ -794,7 +795,11 @@ export const serve_rendered = {
             ctx.fillStyle = 'rgba(0,0,0,.4)';
             ctx.fillText(item.watermark, 5, height - 5);
 
-            image.composite([{ input: canvas.toBuffer() }]);
+            composite_array.push({ input: canvas.toBuffer() });
+          }
+
+          if (composite_array.length > 0) {
+            image.composite(composite_array);
           }
 
           const formatQuality = (options.formatQuality || {})[format];