diff --git a/include/quicer_types.hrl b/include/quicer_types.hrl
index bcdfba76..ccb15060 100644
--- a/include/quicer_types.hrl
+++ b/include/quicer_types.hrl
@@ -158,6 +158,7 @@
                                          , param_conn_disable_1rtt_encryption => boolean()
                                            %% Not working well
                                          , param_conn_local_address => string()
+                                         , _ => _ %% for Application defined options
                                          }.
 -type conn_shutdown_flag() :: ?QUIC_CONNECTION_SHUTDOWN_FLAG_NONE |
                               ?QUIC_CONNECTION_SHUTDOWN_FLAG_SILENT.
@@ -168,6 +169,7 @@
                         , start_flag => stream_start_flags()
                         , event_mask => uint32()
                         , disable_fpbuffer => boolean()
+                        , _ => _ %% for Application defined options
                         }. %% @TODO expand
 
 -type stream_open_flags() ::  ?QUIC_STREAM_OPEN_FLAG_NONE |
diff --git a/src/quicer.erl b/src/quicer.erl
index d79798e3..eb3a2c29 100644
--- a/src/quicer.erl
+++ b/src/quicer.erl
@@ -132,13 +132,37 @@
 
 
 %% export types
--export_type([listener_handle/0,
-              listener_opts/0,
+-export_type([%% handles
+              listener_handle/0,
               listen_on/0,
               connection_handle/0,
-              conn_opts/0,
               stream_handle/0,
-              stream_opts/0
+
+              %% Options
+              conn_opts/0,
+              stream_opts/0,
+              listener_opts/0,
+
+              %% Flags
+              stream_open_flags/0,
+              stream_start_flags/0,
+              stream_shutdown_flags/0,
+
+              %% Events Props
+              recv_data_props/0,
+              peer_accepted_props/0,
+              stream_closed_props/0,
+              stream_start_completed_props/0,
+              transport_shutdown_props/0,
+              conn_closed_props/0,
+              connected_props/0,
+              new_conn_props/0,
+              streams_available_props/0,
+              new_stream_props/0,
+
+              %% Suporting types
+              error_code/0,
+              quicer_addr/0
              ]).
 
 -type connection_opts() :: proplists:proplist() | conn_opts().