--- a/toolkit/moz.configure
+++ b/toolkit/moz.configure
@@ -543,16 +543,17 @@ system_gpsd = pkg_check_modules('MOZ_GPS
 set_config('MOZ_GPSD', depends_if(system_gpsd)(lambda _: True))
 
 # Miscellaneous programs
 # ==============================================================
 
 check_prog('TAR', ('gnutar', 'gtar', 'tar'))
 check_prog('UNZIP', ('unzip',))
 check_prog('ZIP', ('zip',))
+check_prog('GN', ('gn',))
 
 # Key files
 # ==============================================================
 include('../build/moz.configure/keyfiles.configure')
 
 simple_keyfile('Mozilla API')
 
 simple_keyfile('Google API')