diff --git a/tools/gui/BUILD b/tools/gui/BUILD
index 0cec9ea..feadcb5 100644
--- a/tools/gui/BUILD
+++ b/tools/gui/BUILD
@@ -12,6 +12,6 @@
     name = "tools-gui-gulp",
     srcs = [":_tools-gui-gulp-files"],
     outs = ["tools-gui-gulp.jar"],
-    cmd = "cd tools/gui && find . -type f -exec touch -t 201806280000 {} \; && jar Mcf ../../$@ .",
+    cmd = "cd tools/gui && find . -type f -exec touch -t 201806280000 {} \\; && jar Mcf ../../$@ .",
     visibility = ["//visibility:public"],
 )