diff --git a/exercises/practice/reverse-string/test_reverse_string.zig b/exercises/practice/reverse-string/test_reverse_string.zig
index cf58d6d6..01df0306 100644
--- a/exercises/practice/reverse-string/test_reverse_string.zig
+++ b/exercises/practice/reverse-string/test_reverse_string.zig
@@ -4,7 +4,8 @@ const testing = std.testing;
 const reverse_string = @import("reverse_string.zig");
 
 fn testReverse(comptime s: []const u8, expected: []const u8) !void {
-    var buffer: [s.len]u8 = undefined;
+    const buffer_size = 80; // exceeds length of test strings
+    var buffer: [buffer_size]u8 = undefined;
     const actual = reverse_string.reverse(&buffer, s);
     try testing.expectEqualStrings(expected, actual);
 }