diff -r f0fc70b6f8f9 -r 2a6d83f4677e src/chess/fen.c
--- a/src/chess/fen.c	Thu Jul 30 18:34:15 2026 +0200
+++ b/src/chess/fen.c	Thu Jul 30 19:17:38 2026 +0200
@@ -42,7 +42,7 @@
                     str[i++] = '0'+skip;
                     skip = 0;
                 }
-                switch (gamestate->board[row][file] & ~ENPASSANT_THREAT) {
+                switch (piece_at(gamestate, row, file)) {
                 case WHITE|KING: str[i++] = 'K'; break;
                 case WHITE|QUEEN: str[i++] = 'Q'; break;
                 case WHITE|BISHOP: str[i++] = 'B'; break;
@@ -120,11 +120,11 @@
     str[0] = '-';
 
     for (int file = 0 ; file < 8 ; file++) {
-        if (gamestate->board[3][file] & ENPASSANT_THREAT) {
+        if (enpassant_threat_exists(gamestate, 3, file)) {
             str[0] = filechr(file);
             str[1] = rowchr(2);
         }
-        if (gamestate->board[4][file] & ENPASSANT_THREAT) {
+        if (enpassant_threat_exists(gamestate, 4, file)) {
             str[0] = filechr(file);
             str[1] = rowchr(5);
         }
@@ -137,7 +137,7 @@
     unsigned int hm = 0;
     for (unsigned int i = 0; i < gamestate->movecount; i++) {
         if (gamestate->moves[i].capture
-            || (gamestate->moves[i].piece & PIECE_MASK) == PAWN) {
+            || piece_type(gamestate->moves[i].piece) == PAWN) {
             hm = 0;
         } else {
             hm++;