diff --git a/src/lib.zig b/src/lib.zig
index e6fef2acb7524dfec8be854c411c31e00a09cfda..ca7a703af1a2e29bd99a2ab3bb91ad97a1cfcdd4 100644
--- a/src/lib.zig
+++ b/src/lib.zig
@@ -34,11 +34,11 @@ pub fn addSentinel(alloc: *std.mem.Allocator, comptime T: type, input: []const T
 
 const alphabet = "0123456789abcdefghijklmnopqrstuvwxyz";
 
-pub fn randomSlice(alloc: *std.mem.Allocator, rand: *std.rand.Random, comptime T: type, len: usize) ![]T {
+pub fn randomSlice(alloc: *std.mem.Allocator, rand: *const std.rand.Random, comptime T: type, len: usize) ![]T {
     var buf = try alloc.alloc(T, len);
     var i: usize = 0;
     while (i < len) : (i += 1) {
-        buf[i] = alphabet[rand.int(usize) % alphabet.len];
+        buf[i] = alphabet[rand.int(u8) % alphabet.len];
     }
     return buf;
 }