diff --git a/src/gwidth.zig b/src/gwidth.zig
index abf560a..f41f37d 100644
--- a/src/gwidth.zig
+++ b/src/gwidth.zig
@@ -31,7 +31,8 @@ pub fn gwidth(str: []const u8, method: Method) !usize {
         .no_zwj => {
             var out: [256]u8 = undefined;
             if (str.len > out.len) return error.OutOfMemory;
-            const n = std.mem.replace(u8, str, "\u{200D}", "", &out);
+            const n = std.mem.replacementSize(u8, str, "\u{200D}", "");
+            _ = std.mem.replace(u8, str, "\u{200D}", "", &out);
             return gwidth(out[0..n], .unicode);
         },
     }