diff --git a/bulb/bulb.ha b/bulb/bulb.ha
index 198909f..f21b0a5 100644
--- a/bulb/bulb.ha
+++ b/bulb/bulb.ha
@@ -66,10 +66,10 @@ export fn validate_board_name(board: str) (void | invalid_board) = {
 	for (true) match (strings::next(&iter)) {
 	case let run: rune =>
 		if (
-			run: int == '/' ||
-			run: int == '.' ||
-			run: int == '\\' ||
-			run: int == ':') {
+			run: u32 == '/' ||
+			run: u32 == '.' ||
+			run: u32 == '\\' ||
+			run: u32 == ':') {
 			return invalid_board;
 		};
 	case done => return void;