diff --git a/src/rbx.rs b/src/rbx.rs
index 76e5861..46b5476 100644
--- a/src/rbx.rs
+++ b/src/rbx.rs
@@ -63,7 +63,7 @@ impl ModesBuilder{
 		//collect modes and stages into contiguous arrays
 		let mut unique_modes:Vec<(gameplay_modes::ModeId,gameplay_modes::Mode)>
 		=self.modes.into_iter().collect();
-		unique_modes.sort_by(|a,b|a.0.cmp(&b.0));
+		unique_modes.sort_by_key(|&(mode_id,_)|mode_id);
 		let (mut modes,final_mode_id_from_builder_mode_id):(Vec<ModeBuilder>,HashMap<gameplay_modes::ModeId,gameplay_modes::ModeId>)
 		=unique_modes.into_iter().enumerate()
 		.map(|(final_mode_id,(builder_mode_id,mut mode))|{