diff --git a/test/cberl_tests.erl b/test/cberl_tests.erl
index c463767..08b668a 100644
--- a/test/cberl_tests.erl
+++ b/test/cberl_tests.erl
@@ -40,44 +40,44 @@ clean_up(_) ->
 test_set_and_get(_) ->
     Key = <<"testkey">>,
     Value = "testval",
-    ok = cberl:set(?POOLNAME, Key, 0, Value),
+    {ok, CAS1} = cberl:set(?POOLNAME, Key, 0, Value),
     Get1 = cberl:get(?POOLNAME, Key),
-    ok = cberl:set(?POOLNAME, Key, 0, Value, json),
+    {ok, CAS2} = cberl:set(?POOLNAME, Key, 0, Value, json),
     Get2 = cberl:get(?POOLNAME, Key),
-    ok = cberl:set(?POOLNAME, Key, 0, Value, raw_binary),
+    {ok, CAS3} = cberl:set(?POOLNAME, Key, 0, Value, raw_binary),
     Get3 = cberl:get(?POOLNAME, Key),
-    [?_assertMatch({Key, _, Value}, Get1),
-     ?_assertMatch({Key, _, Value}, Get2),
-     ?_assertMatch({Key, _, Value}, Get3)
+    [?_assertMatch({Key, CAS1, Value}, Get1),
+     ?_assertMatch({Key, CAS2, Value}, Get2),
+     ?_assertMatch({Key, CAS3, Value}, Get3)
     ].
 
 test_multi_get(_) ->
     Value = "testval",
     Keys = lists:map(fun(N) -> list_to_binary(integer_to_list(N)) end, lists:seq(1, 1000)),
-    lists:map(fun(Key) -> ok = cberl:set(?POOLNAME, Key, 0, Value) end, Keys),
+    lists:map(fun(Key) -> {ok, _} = cberl:set(?POOLNAME, Key, 0, Value) end, Keys),
     [?_assertMatch({<<"1">>,_, "testval"}, lists:nth(1, cberl:mget(?POOLNAME, Keys)))].
 
 test_replace_add(_) ->
     Key = <<"testkey">>,
     Value = "testval",
-    ok = cberl:set(?POOLNAME, Key, 0, Value),
+    {ok, _} = cberl:set(?POOLNAME, Key, 0, Value),
     AddFail = cberl:add(?POOLNAME, Key, 0, Value),
     AddPass = cberl:add(?POOLNAME, <<"testkey1">>, 0, Value),
     ReplaceFail = cberl:replace(?POOLNAME, <<"notestkey">>, 0, Value),
-    ok = cberl:replace(?POOLNAME, Key, 0, "testval1"),
+    {ok, _} = cberl:replace(?POOLNAME, Key, 0, "testval1"),
     Get1 = cberl:get(?POOLNAME, Key),
     [?_assertEqual({error, key_eexists}, AddFail),
-     ?_assertEqual(ok, AddPass),
+     ?_assertMatch({ok, _}, AddPass),
      ?_assertEqual({error, key_enoent}, ReplaceFail),
      ?_assertMatch({Key, _, "testval1"}, Get1)
     ].
 
 test_append_prepend(_) ->
     Key = <<"testkey">>,
-    ok = cberl:set(?POOLNAME, Key, 0, "base", str),
-    ok = cberl:append(?POOLNAME, Key, "tail"),
+    {ok, _} = cberl:set(?POOLNAME, Key, 0, "base", str),
+    {ok, _} = cberl:append(?POOLNAME, Key, "tail"),
     Get1 = cberl:get(?POOLNAME, Key),
-    ok = cberl:prepend(?POOLNAME, Key, "head"),
+    {ok, _} = cberl:prepend(?POOLNAME, Key, "head"),
     Get2 = cberl:get(?POOLNAME, Key),
     [?_assertMatch({Key, _, "basetail"}, Get1),
      ?_assertMatch({Key, _, "headbasetail"}, Get2)
@@ -86,7 +86,7 @@ test_append_prepend(_) ->
 test_get_and_touch(_) ->
     Key = <<"testkey">>,
     Value = "testval",
-    ok = cberl:set(?POOLNAME, Key, 0, Value),
+    {ok, _} = cberl:set(?POOLNAME, Key, 0, Value),
     cberl:get_and_touch(?POOLNAME, Key, 1),
     timer:sleep(5000),
     [?_assertEqual({Key, {error,key_enoent}}, cberl:get(?POOLNAME, Key))].
@@ -94,7 +94,7 @@ test_get_and_touch(_) ->
 test_touch(_) ->
     Key = <<"testkey">>,
     Value = "testval",
-    ok = cberl:set(?POOLNAME, Key, 0, Value),
+    {ok, _} = cberl:set(?POOLNAME, Key, 0, Value),
     {ok, _} = cberl:touch(?POOLNAME, Key, 1),
     timer:sleep(5000),
     [?_assertEqual({Key, {error,key_enoent}}, cberl:get(?POOLNAME, Key))].
@@ -102,7 +102,7 @@ test_touch(_) ->
 test_remove(_) ->
     Key = <<"testkey">>,
     Value = "testval",
-    ok = cberl:set(?POOLNAME, Key, 0, Value),
+    {ok, _} = cberl:set(?POOLNAME, Key, 0, Value),
     ok = cberl:remove(?POOLNAME, Key),
     [?_assertEqual({Key, {error,key_enoent}}, cberl:get(?POOLNAME, Key))].
 
@@ -110,18 +110,18 @@ test_lock(_) ->
     Key = <<"testkey">>,
     Value = "testval",
     Value2 = "testval2",
-    ok = cberl:set(?POOLNAME, Key, 0, Value),
+    {ok, _} = cberl:set(?POOLNAME, Key, 0, Value),
     {Key, CAS, _Exp} = cberl:get_and_lock(?POOLNAME, Key, 100000),
     fun () ->
         [?assertEqual({error,key_eexists}, cberl:set(?POOLNAME, Key, 0, Value2)),
          ?assertEqual(ok, cberl:unlock(?POOLNAME, Key, CAS)),
-         ?assertEqual(ok, cberl:set(?POOLNAME, Key, 0, Value2))]
+         ?assertMatch({ok, _}, cberl:set(?POOLNAME, Key, 0, Value2))]
     end.
 
 test_flush(_) ->
     Key = <<"testkey">>,
     Value = "testval",
-    ok = cberl:set(?POOLNAME, Key, 0, Value),
+    {ok, _} = cberl:set(?POOLNAME, Key, 0, Value),
     fun() ->
         [?assertMatch(ok, cberl:flush(?POOLNAME, "default")),
          ?assertMatch({Key, {error, key_enoent}}, cberl:get(?POOLNAME, Key))]
@@ -130,7 +130,7 @@ test_flush(_) ->
 test_flush_1(_) ->
     Key = <<"testkey">>,
     Value = "testval",
-    ok = cberl:set(?POOLNAME, Key, 0, Value),
+    {ok, _} = cberl:set(?POOLNAME, Key, 0, Value),
     fun() ->
         [?assertMatch(ok, cberl:flush(?POOLNAME)),
          ?assertMatch({Key, {error, key_enoent}}, cberl:get(?POOLNAME, Key))]