diff --git a/build.js b/build.js
index 340c0b93b..95944f97b 100755
--- a/build.js
+++ b/build.js
@@ -220,6 +220,7 @@
     'max',
     'min',
     'mixin',
+    'once',
     'pick',
     'reduce',
     'reduceRight',
diff --git a/test/backbone.html b/test/backbone.html
index 6af89c5bc..0392a66eb 100644
--- a/test/backbone.html
+++ b/test/backbone.html
@@ -29,10 +29,15 @@
 			);
 		</script>
 		<script src="test-ui.js"></script>
+		<script src="../lodash.js"></script>
 		<script>
+			var lodash = _.noConflict();
 			document.write('<script src="../' + ui.buildPath + '"><\/script>');
 		</script>
 		<script>
+			_.mixin({
+				'debounce': lodash.debounce
+			});
 			if (!_.chain) {
 				_.mixin({
 					'chain': function(value) {
diff --git a/test/test-build.js b/test/test-build.js
index 31c716294..d59674686 100644
--- a/test/test-build.js
+++ b/test/test-build.js
@@ -229,6 +229,7 @@
     'max',
     'min',
     'mixin',
+    'once',
     'pick',
     'reduce',
     'reduceRight',