diff --git a/ui/build/config.go b/ui/build/config.go
index cbf1986..e140867 100644
--- a/ui/build/config.go
+++ b/ui/build/config.go
@@ -1326,6 +1326,10 @@
 	return filepath.Join(c.OutDir(), "build"+c.KatiSuffix()+katiPackageSuffix+".ninja")
 }
 
+func (c *configImpl) SoongVarsFile() string {
+	return filepath.Join(c.SoongOutDir(), "soong.variables")
+}
+
 func (c *configImpl) SoongNinjaFile() string {
 	return filepath.Join(c.SoongOutDir(), "build.ninja")
 }