diff --git a/Libraries/LibJS/Forward.h b/Libraries/LibJS/Forward.h
index bb4f0499ba..36895e6587 100644
--- a/Libraries/LibJS/Forward.h
+++ b/Libraries/LibJS/Forward.h
@@ -32,6 +32,7 @@ class ASTNode;
 class Argument;
 class Cell;
 class Expression;
+class Function;
 class Heap;
 class HeapBlock;
 class Interpreter;