diff --git a/src/emqx.erl b/src/emqx.erl
index 79356d38b..097b4b6c5 100644
--- a/src/emqx.erl
+++ b/src/emqx.erl
@@ -29,16 +29,18 @@
         , stop/0
         ]).
 
+-export([ get_env/1
+        , get_env/2
+        ]).
+
 %% PubSub API
 -export([ subscribe/1
         , subscribe/2
         , subscribe/3
+        , publish/1
+        , unsubscribe/1
         ]).
 
--export([publish/1]).
-
--export([unsubscribe/1]).
-
 %% PubSub management API
 -export([ topics/0
         , subscriptions/1
@@ -101,6 +103,15 @@ is_running(Node) ->
         Pid when is_pid(Pid) -> true
     end.
 
+%% @doc Get environment
+-spec(get_env(Key :: atom()) -> maybe(term())).
+get_env(Key) ->
+    get_env(Key, undefined).
+
+-spec(get_env(Key :: atom(), Default :: term()) -> term()).
+get_env(Key, Default) ->
+    application:get_env(?APP, Key, Default).
+
 %%--------------------------------------------------------------------
 %% PubSub API
 %%--------------------------------------------------------------------
diff --git a/src/emqx_broker.erl b/src/emqx_broker.erl
index 359e65ab8..f171d3e98 100644
--- a/src/emqx_broker.erl
+++ b/src/emqx_broker.erl
@@ -236,7 +236,7 @@ route(Routes, Delivery) ->
 do_route({To, Node}, Delivery) when Node =:= node() ->
     {Node, To, dispatch(To, Delivery)};
 do_route({To, Node}, Delivery) when is_atom(Node) ->
-    {Node, To, forward(Node, To, Delivery, emqx_config:get_env(rpc_mode, async))};
+    {Node, To, forward(Node, To, Delivery, emqx:get_env(rpc_mode, async))};
 do_route({To, Group}, Delivery) when is_tuple(Group); is_binary(Group) ->
     {share, To, emqx_shared_sub:dispatch(Group, To, Delivery)}.
 
diff --git a/src/emqx_cm_locker.erl b/src/emqx_cm_locker.erl
index c5cd9c2f6..874863b63 100644
--- a/src/emqx_cm_locker.erl
+++ b/src/emqx_cm_locker.erl
@@ -62,5 +62,5 @@ unlock(ClientId) ->
 
 -spec(strategy() -> local | one | quorum | all).
 strategy() ->
-    emqx_config:get_env(session_locking_strategy, quorum).
+    emqx:get_env(session_locking_strategy, quorum).
 
diff --git a/src/emqx_cm_registry.erl b/src/emqx_cm_registry.erl
index ce843a427..04dd04e80 100644
--- a/src/emqx_cm_registry.erl
+++ b/src/emqx_cm_registry.erl
@@ -62,7 +62,7 @@ start_link() ->
 %% @doc Is the global registry enabled?
 -spec(is_enabled() -> boolean()).
 is_enabled() ->
-    emqx_config:get_env(enable_channel_registry, true).
+    emqx:get_env(enable_channel_registry, true).
 
 %% @doc Register a global channel.
 -spec(register_channel(emqx_types:client_id()
diff --git a/src/emqx_config.erl b/src/emqx_config.erl
deleted file mode 100644
index bef0302f6..000000000
--- a/src/emqx_config.erl
+++ /dev/null
@@ -1,32 +0,0 @@
-%%--------------------------------------------------------------------
-%% Copyright (c) 2019 EMQ Technologies Co., Ltd. All Rights Reserved.
-%%
-%% Licensed under the Apache License, Version 2.0 (the "License");
-%% you may not use this file except in compliance with the License.
-%% You may obtain a copy of the License at
-%%
-%%     http://www.apache.org/licenses/LICENSE-2.0
-%%
-%% Unless required by applicable law or agreed to in writing, software
-%% distributed under the License is distributed on an "AS IS" BASIS,
-%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-%% See the License for the specific language governing permissions and
-%% limitations under the License.
-%%--------------------------------------------------------------------
-
--module(emqx_config).
-
--export([ get_env/1
-        , get_env/2
-        ]).
-
--define(APP, emqx).
-
-%% @doc Get environment
--spec(get_env(Key :: atom()) -> term() | undefined).
-get_env(Key) ->
-    get_env(Key, undefined).
-
--spec(get_env(Key :: atom(), Default :: term()) -> term()).
-get_env(Key, Default) ->
-    application:get_env(?APP, Key, Default).
diff --git a/src/emqx_flapping.erl b/src/emqx_flapping.erl
index ba3f444b7..0a9a62d56 100644
--- a/src/emqx_flapping.erl
+++ b/src/emqx_flapping.erl
@@ -105,7 +105,7 @@ start_link() ->
     gen_statem:start_link({local, ?MODULE}, ?MODULE, [], []).
 
 init([]) ->
-    Interval = emqx_config:get_env(flapping_clean_interval, ?default_flapping_clean_interval),
+    Interval = emqx:get_env(flapping_clean_interval, ?default_flapping_clean_interval),
     TabOpts = [ public
               , set
               , {keypos, 2}
diff --git a/src/emqx_listeners.erl b/src/emqx_listeners.erl
index 802179065..036b60e10 100644
--- a/src/emqx_listeners.erl
+++ b/src/emqx_listeners.erl
@@ -42,7 +42,7 @@
 %% @doc Start all listeners.
 -spec(start() -> ok).
 start() ->
-    lists:foreach(fun start_listener/1, emqx_config:get_env(listeners, [])).
+    lists:foreach(fun start_listener/1, emqx:get_env(listeners, [])).
 
 -spec(start_listener(listener()) -> {ok, pid()} | {error, term()}).
 start_listener({Proto, ListenOn, Options}) ->
@@ -113,7 +113,7 @@ with_port({Addr, Port}, Opts = #{socket_opts := SocketOption}) ->
 %% @doc Restart all listeners
 -spec(restart() -> ok).
 restart() ->
-    lists:foreach(fun restart_listener/1, emqx_config:get_env(listeners, [])).
+    lists:foreach(fun restart_listener/1, emqx:get_env(listeners, [])).
 
 -spec(restart_listener(listener()) -> any()).
 restart_listener({Proto, ListenOn, Options}) ->
@@ -136,7 +136,7 @@ restart_listener(Proto, ListenOn, _Opts) ->
 %% @doc Stop all listeners.
 -spec(stop() -> ok).
 stop() ->
-    lists:foreach(fun stop_listener/1, emqx_config:get_env(listeners, [])).
+    lists:foreach(fun stop_listener/1, emqx:get_env(listeners, [])).
 
 -spec(stop_listener(listener()) -> ok | {error, term()}).
 stop_listener({Proto, ListenOn, Opts}) ->
diff --git a/src/emqx_mod_acl_internal.erl b/src/emqx_mod_acl_internal.erl
index 2629ed60a..36e4f67ff 100644
--- a/src/emqx_mod_acl_internal.erl
+++ b/src/emqx_mod_acl_internal.erl
@@ -79,8 +79,7 @@ reload_acl() ->
 %% Internal Functions
 %%--------------------------------------------------------------------
 
-acl_file() ->
-    emqx_config:get_env(acl_file).
+acl_file() -> emqx:get_env(acl_file).
 
 lookup(PubSub, Rules) ->
     maps:get(PubSub, Rules, []).
diff --git a/src/emqx_modules.erl b/src/emqx_modules.erl
index c96cd6c15..6ba69e1fd 100644
--- a/src/emqx_modules.erl
+++ b/src/emqx_modules.erl
@@ -34,8 +34,7 @@ load({Mod, Env}) ->
     ok = Mod:load(Env),
     ?LOG(info, "Load ~s module successfully.", [Mod]).
 
-modules() ->
-    emqx_config:get_env(modules, []).
+modules() -> emqx:get_env(modules, []).
 
 %% @doc Unload all the extended modules.
 -spec(unload() -> ok).
diff --git a/src/emqx_plugins.erl b/src/emqx_plugins.erl
index e75a70e83..4a597fda6 100644
--- a/src/emqx_plugins.erl
+++ b/src/emqx_plugins.erl
@@ -39,7 +39,7 @@
 %% @doc Init plugins' config
 -spec(init() -> ok).
 init() ->
-    case emqx_config:get_env(plugins_etc_dir) of
+    case emqx:get_env(plugins_etc_dir) of
         undefined  -> ok;
         PluginsEtc ->
             CfgFiles = [filename:join(PluginsEtc, File) ||
@@ -57,16 +57,15 @@ init_config(CfgFile) ->
 -spec(load() -> list() | {error, term()}).
 load() ->
     load_expand_plugins(),
-    case emqx_config:get_env(plugins_loaded_file) of
-        undefined -> %% No plugins available
-            ignore;
+    case emqx:get_env(plugins_loaded_file) of
+        undefined -> ignore; %% No plugins available
         File ->
             ensure_file(File),
             with_loaded_file(File, fun(Names) -> load_plugins(Names, false) end)
     end.
 
 load_expand_plugins() ->
-    case emqx_config:get_env(expand_plugins_dir) of
+    case emqx:get_env(expand_plugins_dir) of
         undefined -> ok;
         ExpandPluginsDir ->
             Plugins = filelib:wildcard("*", ExpandPluginsDir),
@@ -138,9 +137,8 @@ load_plugins(Names, Persistent) ->
 %% @doc Unload all plugins before broker stopped.
 -spec(unload() -> list() | {error, term()}).
 unload() ->
-    case emqx_config:get_env(plugins_loaded_file) of
-        undefined ->
-            ignore;
+    case emqx:get_env(plugins_loaded_file) of
+        undefined -> ignore;
         File ->
             with_loaded_file(File, fun stop_plugins/1)
     end.
@@ -300,7 +298,7 @@ plugin_unloaded(Name, true) ->
     end.
 
 read_loaded() ->
-    case emqx_config:get_env(plugins_loaded_file) of
+    case emqx:get_env(plugins_loaded_file) of
         undefined -> {error, not_found};
         File      -> read_loaded(File)
     end.
@@ -308,7 +306,7 @@ read_loaded() ->
 read_loaded(File) -> file:consult(File).
 
 write_loaded(AppNames) ->
-    FilePath = emqx_config:get_env(plugins_loaded_file),
+    FilePath = emqx:get_env(plugins_loaded_file),
     case file:write_file(FilePath, [io_lib:format("~p.~n", [Name]) || Name <- AppNames]) of
         ok -> ok;
         {error, Error} ->
diff --git a/src/emqx_shared_sub.erl b/src/emqx_shared_sub.erl
index 66be8ee81..71a20b20c 100644
--- a/src/emqx_shared_sub.erl
+++ b/src/emqx_shared_sub.erl
@@ -127,11 +127,11 @@ dispatch(Group, Topic, Delivery = #delivery{message = Msg}, FailedSubs) ->
 
 -spec(strategy() -> random | round_robin | sticky | hash).
 strategy() ->
-    emqx_config:get_env(shared_subscription_strategy, round_robin).
+    emqx:get_env(shared_subscription_strategy, round_robin).
 
 -spec(ack_enabled() -> boolean()).
 ack_enabled() ->
-    emqx_config:get_env(shared_dispatch_ack_enabled, false).
+    emqx:get_env(shared_dispatch_ack_enabled, false).
 
 do_dispatch(SubPid, Topic, Msg, _Type) when SubPid =:= self() ->
     %% Deadlock otherwise
diff --git a/src/emqx_sys.erl b/src/emqx_sys.erl
index 41b27729b..66c3d2dc1 100644
--- a/src/emqx_sys.erl
+++ b/src/emqx_sys.erl
@@ -111,12 +111,12 @@ datetime() ->
 %% @doc Get sys interval
 -spec(sys_interval() -> pos_integer()).
 sys_interval() ->
-    emqx_config:get_env(broker_sys_interval, 60000).
+    emqx:get_env(broker_sys_interval, 60000).
 
 %% @doc Get sys heatbeat interval
 -spec(sys_heatbeat_interval() -> pos_integer()).
 sys_heatbeat_interval() ->
-    emqx_config:get_env(broker_sys_heartbeat, 30000).
+    emqx:get_env(broker_sys_heartbeat, 30000).
 
 %% @doc Get sys info
 -spec(info() -> list(tuple())).
diff --git a/src/emqx_sys_sup.erl b/src/emqx_sys_sup.erl
index cbc07650e..7a94c4288 100644
--- a/src/emqx_sys_sup.erl
+++ b/src/emqx_sys_sup.erl
@@ -48,6 +48,5 @@ child_spec(Mod, Args) ->
       modules => [Mod]
      }.
 
-config(Name) ->
-    emqx_config:get_env(Name, []).
+config(Name) -> emqx:get_env(Name, []).
 
diff --git a/src/emqx_zone.erl b/src/emqx_zone.erl
index bac32b849..7a93037b1 100644
--- a/src/emqx_zone.erl
+++ b/src/emqx_zone.erl
@@ -66,18 +66,17 @@ start_link() ->
     gen_server:start_link({local, ?SERVER}, ?MODULE, [], []).
 
 -spec(get_env(maybe(zone()), atom()) -> maybe(term())).
-get_env(undefined, Key) ->
-    emqx_config:get_env(Key);
+get_env(undefined, Key) -> emqx:get_env(Key);
 get_env(Zone, Key) ->
     get_env(Zone, Key, undefined).
 
 -spec(get_env(maybe(zone()), atom(), term()) -> maybe(term())).
 get_env(undefined, Key, Def) ->
-    emqx_config:get_env(Key, Def);
+    emqx:get_env(Key, Def);
 get_env(Zone, Key, Def) ->
     try persistent_term:get(?KEY(Zone, Key))
     catch error:badarg ->
-        emqx_config:get_env(Key, Def)
+        emqx:get_env(Key, Def)
     end.
 
 -spec(set_env(zone(), atom(), term()) -> ok).
@@ -132,5 +131,5 @@ code_change(_OldVsn, State, _Extra) ->
 
 do_reload() ->
     [persistent_term:put(?KEY(Zone, Key), Val)
-      || {Zone, Opts} <- emqx_config:get_env(zones, []), {Key, Val} <- Opts].
+      || {Zone, Opts} <- emqx:get_env(zones, []), {Key, Val} <- Opts].
 
diff --git a/test/emqx_SUITE.erl b/test/emqx_SUITE.erl
index c26028c76..96c76b3e6 100644
--- a/test/emqx_SUITE.erl
+++ b/test/emqx_SUITE.erl
@@ -32,6 +32,14 @@ init_per_suite(Config) ->
 end_per_suite(_Config) ->
     emqx_ct_helpers:stop_apps([]).
 
+t_get_env(_) ->
+    ?assertEqual(undefined, emqx:get_env(undefined_key)),
+    ?assertEqual(default_value, emqx:get_env(undefined_key, default_value)),
+    application:set_env(emqx, undefined_key, hello),
+    ?assertEqual(hello, emqx:get_env(undefined_key)),
+    ?assertEqual(hello, emqx:get_env(undefined_key, default_value)),
+    application:unset_env(emqx, undefined_key).
+
 t_emqx_pubsub_api(_) ->
     emqx:start(),
     true = emqx:is_running(node()),
diff --git a/test/emqx_config_SUITE.erl b/test/emqx_config_SUITE.erl
deleted file mode 100644
index 5014e3ef3..000000000
--- a/test/emqx_config_SUITE.erl
+++ /dev/null
@@ -1,39 +0,0 @@
-%%--------------------------------------------------------------------
-%% Copyright (c) 2019 EMQ Technologies Co., Ltd. All Rights Reserved.
-%%
-%% Licensed under the Apache License, Version 2.0 (the "License");
-%% you may not use this file except in compliance with the License.
-%% You may obtain a copy of the License at
-%%
-%%     http://www.apache.org/licenses/LICENSE-2.0
-%%
-%% Unless required by applicable law or agreed to in writing, software
-%% distributed under the License is distributed on an "AS IS" BASIS,
-%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-%% See the License for the specific language governing permissions and
-%% limitations under the License.
-%%--------------------------------------------------------------------
-
--module(emqx_config_SUITE).
-
--compile(export_all).
--compile(nowarn_export_all).
-
--include_lib("eunit/include/eunit.hrl").
-
-all() -> emqx_ct:all(?MODULE).
-
-init_per_suite(Config) ->
-    emqx_ct_helpers:start_apps([]),
-    Config.
-
-end_per_suite(_Config) ->
-    emqx_ct_helpers:stop_apps([]).
-
-t_get_env(_) ->
-    ?assertEqual(undefined, emqx_config:get_env(undefined_key)),
-    ?assertEqual(default_value, emqx_config:get_env(undefined_key, default_value)),
-    application:set_env(emqx, undefined_key, hello),
-    ?assertEqual(hello, emqx_config:get_env(undefined_key)),
-    ?assertEqual(hello, emqx_config:get_env(undefined_key, default_value)),
-    application:unset_env(emqx, undefined_key).
\ No newline at end of file