diff -r ea12a3bb4b33 -r 2d81494f54b3 rt/mojo/src/main/java/org/apidesign/bck2brwsr/mojo/AheadOfTime.java
--- a/rt/mojo/src/main/java/org/apidesign/bck2brwsr/mojo/AheadOfTime.java	Tue Feb 24 11:12:53 2015 +0100
+++ b/rt/mojo/src/main/java/org/apidesign/bck2brwsr/mojo/AheadOfTime.java	Wed Feb 25 11:31:50 2015 +0100
@@ -114,7 +114,7 @@
             if ("provided".equals(a.getScope())) {
                 continue;
             }
-            File aot = new File(prj.getBuild().getDirectory(), classPathPrefix);
+            File aot = new File(mainJavaScript.getParent(), classPathPrefix);
             aot.mkdirs();
             File js = new File(aot, n.substring(0, n.length() - 4) + ".js");
             if (js.exists()) {