diff -r 31d73d150c76 -r d20887f0e8b3 src/chess/fen.c
--- a/src/chess/fen.c	Thu Sep 03 12:13:05 2026 +0200
+++ b/src/chess/fen.c	Thu Sep 03 15:28:54 2026 +0200
@@ -44,18 +44,18 @@
                     skip = 0;
                 }
                 switch (piece_at(gamestate, file, rank)) {
-                case WHITE|KING: str[i++] = 'K'; break;
-                case WHITE|QUEEN: str[i++] = 'Q'; break;
-                case WHITE|BISHOP: str[i++] = 'B'; break;
-                case WHITE|KNIGHT: str[i++] = 'N'; break;
-                case WHITE|ROOK: str[i++] = 'R'; break;
-                case WHITE|PAWN: str[i++] = 'P'; break;
-                case BLACK|KING: str[i++] = 'k'; break;
-                case BLACK|QUEEN: str[i++] = 'q'; break;
-                case BLACK|BISHOP: str[i++] = 'b'; break;
-                case BLACK|KNIGHT: str[i++] = 'n'; break;
-                case BLACK|ROOK: str[i++] = 'r'; break;
-                case BLACK|PAWN: str[i++] = 'p'; break;
+                case WKING: str[i++] = 'K'; break;
+                case WQUEEN: str[i++] = 'Q'; break;
+                case WBISHOP: str[i++] = 'B'; break;
+                case WKNIGHT: str[i++] = 'N'; break;
+                case WROOK: str[i++] = 'R'; break;
+                case WPAWN: str[i++] = 'P'; break;
+                case BKING: str[i++] = 'k'; break;
+                case BQUEEN: str[i++] = 'q'; break;
+                case BBISHOP: str[i++] = 'b'; break;
+                case BKNIGHT: str[i++] = 'n'; break;
+                case BROOK: str[i++] = 'r'; break;
+                case BPAWN: str[i++] = 'p'; break;
                 }
             } else {
                 skip++;