diff --git a/lib/optimize-js.js b/lib/optimize-js.js
index 8f3231cb8..ef2457614 100644
--- a/lib/optimize-js.js
+++ b/lib/optimize-js.js
@@ -386,6 +386,30 @@ const performanceReplacements = [
       $elm$core$Set$empty,
       set);
   });`
+  },
+  {
+    target: `var $elm$core$Basics$composeL = F3(
+	function (g, f, x) {
+		return g(
+			f(x));
+	});`,
+    replacement: `var $elm$core$Basics$composeL = F2(function $elm$core$Basics$composeL$fn(g, f) {
+  return function(x) {
+    return g(f(x));
+  };
+});`
+  },
+  {
+    target: `var $elm$core$Basics$composeR = F3(
+	function (f, g, x) {
+		return g(
+			f(x));
+	});`,
+    replacement: `var $elm$core$Basics$composeR = F2(function $elm$core$Basics$composeR$fn(f, g) {
+  return function(x) {
+    return g(f(x));
+  };
+});`
   }
 ];