diff --git a/src/aeb_fate_data.erl b/src/aeb_fate_data.erl
index e5e07f0..04f78e2 100644
--- a/src/aeb_fate_data.erl
+++ b/src/aeb_fate_data.erl
@@ -115,7 +115,7 @@ make_channel(X) ->     ?FATE_CHANNEL(X).
 make_integer(I) when is_integer(I) -> ?MAKE_FATE_INTEGER(I).
 make_bits(I)    when is_integer(I) -> ?FATE_BITS(I).
 make_string(S)  when is_list(S) ->
-    ?FATE_STRING(list_to_binary(lists:flatten(S)));
+    ?FATE_STRING(iolist_to_binary(S));
 make_string(S)  when is_binary(S) -> ?FATE_STRING(S).
 
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