diff --git a/test/proper_tests.erl b/test/proper_tests.erl
index 1bccf40..8f8c6c5 100644
--- a/test/proper_tests.erl
+++ b/test/proper_tests.erl
@@ -1,6 +1,5 @@
 -module(proper_tests).
 -include_lib("proper/include/proper.hrl").
-%%-include_lib("proper_stdlib/include/proper_ct.hrl").
 -include_lib("eunit/include/eunit.hrl").
 -export([proper_test_/0]).
 
@@ -9,25 +8,27 @@ all() -> proper_ct:testcases(?MODULE).
 init_per_testcase(tc_prop_foo, Config) ->
      [{proper, [{numtests, 1000}]} | Config].
 
--type json_any()    :: json_list()
-                     | json_dict()
-                     | json_number()
-                     | json_string()
-                     | json_null().
--type json_list()   :: list(json_any()).
--type json_dict()   :: {[{json_key(), json_any()}]}.
--type json_key()    :: binary().
--type json_number() :: integer() | float().
--type json_string() :: binary().
--type json_null()   :: null.
+%% Helper funs
+
+escaped_char() ->
+    ?LET(C, char(),
+         case C == $" of
+             true  -> "\\\"";
+             false -> C
+         end).
+
+escaped_utf8_bin() ->
+    ?SUCHTHAT(Bin,
+              ?LET(S, ?SUCHTHAT(L, list(escaped_char()), L /= []),
+                   unicode:characters_to_binary(S, unicode, utf8)),
+              is_binary(Bin)).
 
 %% Atomic types
 json_null() ->
     null.
 
 json_string() ->
-    ?LET(Str, proper_stdgen:utf8_bin(),
-         binary:replace(Str, <<"\"">>, <<"\\\"">>, [global])). %good enough
+    escaped_utf8_bin().
 
 json_number() ->
     oneof([integer(), float()]).
@@ -44,46 +45,39 @@ json_atomic() ->
 %% Compound types
 json_object() ->
     ?SIZED(S, json_object(S)).
-json_object(0) ->
+json_object(S) when S =< 0 ->
     json_atomic();
 json_object(S) ->
     frequency([{1, json_object(0)},
-               {3, json_list()},
-               {9, ?LAZY(
+               {3, ?LAZY(json_list(S))},
+               {3, ?LAZY(
                       ?LETSHRINK(
-                         [Node],
-                         [{list({json_string(), json_object(S - 1)})}],
-                         Node
-                        ))}]).
+                         [ObjectSize],
+                         [integer(1, S)],
+                         ?LETSHRINK(
+                            [Object],
+                            [{vector(ObjectSize,
+                                     {json_string(),
+                                      json_object(S - ObjectSize)})}],
+                            Object
+                           )))}]).
+
+json_list(S) ->
+    ?LETSHRINK([ListSize],
+               [integer(1, S)],
+               vector(ListSize, json_object(S - ListSize))).
 
 json_list() ->
     list(json_object()).
 
-tree(G) ->
-  ?SIZED(S, tree(S, G)).
-tree(0, _) ->
-    leaf;
-tree(S, G) ->
-    frequency([
-               {1, tree(0, G)},
-               {9, ?LAZY(
-                      ?LETSHRINK(
-                         [L, R],
-                         [tree(S div 2, G), tree(S div 2, G)],
-                         {node, G, L, R}
-                        ))}
-              ]).
-
 prop_foo() ->
-%%    ?FORALL(Data, json_any(),
-%%            Data == jiffy:decode(jiffy:encode(Data))).
     ?FORALL(Data, json_object(),
             begin
-                %io:format(user, "Data: ~p~n", [Data]),
+%%                io:format(user, "Data: ~p~n", [Data]),
                 Data == jiffy:decode(jiffy:encode(Data))
             end).
 
 proper_test_() ->
-    {timeout, 600,
+    {timeout, 3600,
      ?_assertEqual([], proper:module(proper_tests, [{to_file, user},
-                                                    {numtests, 10}]))}.
+                                                    {numtests, 1000}]))}.