diff --git a/script/cibuild b/script/cibuild
index 1d03314f7774..a23ce30ef89f 100755
--- a/script/cibuild
+++ b/script/cibuild
@@ -43,9 +43,11 @@ def main():
       deps += LINUX_DEPS_ARM
     execute(['sudo', 'apt-get', 'install'] + deps)
 
-    os.environ['DISPLAY'] = ':99.0'
     execute(['sh', '-e', '/etc/init.d/xvfb', 'start'])
 
+  if PLATFORM == 'linux':
+    os.environ['DISPLAY'] = ':99.0'
+
   rm_rf(os.path.join(SOURCE_ROOT, 'out'))
   rm_rf(os.path.join(SOURCE_ROOT, 'frameworks'))
   rm_rf(os.path.join(SOURCE_ROOT, 'external_binaries'))