--- a/src/chess/bishop.h	Thu Jul 30 18:34:15 2026 +0200
+++ b/src/chess/bishop.h	Thu Jul 30 19:17:38 2026 +0200
@@ -36,8 +36,8 @@
 extern "C" {
 #endif
 
-bool bishop_chkrules(Move *move);
-bool bishop_isblocked(GameState *gamestate, Move *move);
+bool bishop_chkrules(const Move *move);
+bool bishop_isblocked(const GameState *gamestate, const Move *move);
 
 #ifdef	__cplusplus
 }