diff --git a/picotls/picotls.nim b/picotls/picotls.nim
index 765abad..5f8b44e 100644
--- a/picotls/picotls.nim
+++ b/picotls/picotls.nim
@@ -85,7 +85,7 @@ type
     version*: uint16
 
   ptls_iovec_t* {.bycopy.} = object
-    base*: uint8
+    base*: ptr uint8
     len*: csize_t
 
   ptls_on_client_hello_parameters_t* {.bycopy.} = object
@@ -276,5 +276,7 @@ type
 
 var ptls_get_time* {.importc.}: ptls_get_time_t
 
+proc ptls_iovec_init*(p: pointer, len: csize_t): ptls_iovec_t {.cdecl, importc.}
+
 proc ptls_load_certificates*(ctx: ptr ptls_context_t, cert_pem_file: cstring):
                             cint {.cdecl, importc.}
diff --git a/quicly/constants.nim b/quicly/constants.nim
index 8adaa03..5d65bd0 100644
--- a/quicly/constants.nim
+++ b/quicly/constants.nim
@@ -9,6 +9,8 @@ from sendstate import
   quicly_sendstate_t,
   quicly_sendstate_is_open
 
+const QUICLY_ERROR_FREE_CONNECTION* = 0xff03
+
 type
   quicly_stream_id_t* {.bycopy.} = int64
 
diff --git a/quicly/quicly.nim b/quicly/quicly.nim
index abadac4..40cdb5e 100644
--- a/quicly/quicly.nim
+++ b/quicly/quicly.nim
@@ -1,7 +1,14 @@
 from cc import quicly_cc_t
 from cid import quicly_cid_t, quicly_cid_encryptor_t, quicly_cid_plaintext_t
 from loss import quicly_loss_conf_t
-from nativesockets import SockAddr, Sockaddr_in, Sockaddr_in6, SockLen
+from posix import IOVec
+
+from nativesockets import
+  SockAddr,
+  Sockaddr_storage,
+  Sockaddr_in,
+  Sockaddr_in6,
+  SockLen
 
 from constants import
   quicly_conn_t,
@@ -19,14 +26,15 @@ from ../picotls/picotls import
   ptls_iovec_t
 
 export
+  quicly_conn_t,
   quicly_stream_t,
   quicly_stream_id_t
 
 type
   quicly_address_t* {.bycopy.} = object
-    sa: SockAddr
-    sin: Sockaddr_in
-    sin6: Sockaddr_in6
+    sa*: SockAddr
+    sin*: Sockaddr_in
+    sin6*: Sockaddr_in6
 
   Retry* {.bycopy.} = object
     original_dcid*: quicly_cid_t
@@ -190,40 +198,54 @@ proc quicly_free*(conn: ptr quicly_conn_t): cint {.cdecl, importc.}
 proc quicly_decode_packet*(ctx: ptr quicly_context_t,
                            packet: ptr quicly_decoded_packet_t,
                            datagram: ptr uint8, datagram_size: csize_t,
-                           off: csize_t): csize_t
+                           off: ptr csize_t): csize_t
                           {.cdecl, importc.}
 
-proc quicly_is_destination*(conn: ptr quicly_conn_t, dest_addr: ptr SockAddr,
-                            src_addr: ptr SockAddr,
+proc quicly_is_destination*(conn: ptr quicly_conn_t,
+                            dest_addr: ptr SockAddr | ptr Sockaddr_storage,
+                            src_addr: ptr SockAddr | ptr Sockaddr_storage,
                             decoded: ptr quicly_decoded_packet_t): cint
                            {.cdecl, importc.}
 
-proc quicly_receive*(conn: ptr quicly_conn_t, dest_addr: ptr SockAddr,
-                     src_addr: ptr SockAddr,
+proc quicly_receive*(conn: ptr quicly_conn_t,
+                     dest_addr: ptr SockAddr | ptr Sockaddr_storage,
+                     src_addr: ptr SockAddr | ptr Sockaddr_storage,
                      packet: ptr quicly_decoded_packet_t): cint
                     {.cdecl, importc.}
 
+proc quicly_send*(conn: ptr quicly_conn_t, dest: ptr quicly_address_t,
+                  src: ptr quicly_address_t, datagrams: ptr IOVec,
+                  num_diagrams: ptr csize_t, buf: pointer, bufsize: csize_t):
+                 cint {.cdecl, importc.}
+
 proc quicly_accept*(conn: ptr ptr quicly_conn_t, ctx: ptr quicly_context_t,
-                    dest_addr: ptr SockAddr, src_addr: ptr SockAddr,
+                    dest_addr: ptr SockAddr | ptr Sockaddr_storage,
+                    src_addr: ptr SockAddr | ptr Sockaddr_storage,
                     packet: ptr quicly_decoded_packet_t,
                     address_token: ptr quicly_address_token_plaintext_t,
                     new_cid: ptr quicly_cid_plaintext_t,
                     handshake_properties: ptr ptls_handshake_properties_t): cint
                    {.cdecl, importc.}
 
-proc quicly_connect*(conn: ptr ptr quicly_conn_t, server_name: cstring,
-                     dest_addr: ptr SockAddr, src_addr: ptr SockAddr,
+proc quicly_connect*(conn: ptr ptr quicly_conn_t, ctx: ptr quicly_context_t,
+                     server_name: cstring,
+                     dest_addr: ptr SockAddr | ptr Sockaddr_storage,
+                     src_addr: ptr SockAddr | ptr Sockaddr_storage,
                      new_cid: ptr quicly_cid_plaintext_t,
-                     address_token: ptr quicly_address_token_plaintext_t,
+                     address_token: ptls_iovec_t,
                      handshake_properties: ptr ptls_handshake_properties_t,
                      resumed_transport_params: ptr quicly_transport_parameters_t):
                     cint {.cdecl, importc.}
 
+proc quicly_open_stream*(conn: ptr quicly_conn_t,
+                         stream: ptr ptr quicly_stream_t, unidirectional: cint):
+                        cint {.cdecl, importc.}
+
 proc quicly_amend_ptls_context*(ptls: ptr ptls_context_t)
                                {.cdecl, importc.}
 
-proc quicly_get_socklen*(sa: ptr SockAddr): SockLen
+proc quicly_get_socklen*(sa: ptr SockAddr | ptr Sockaddr_storage): SockLen
                         {.cdecl, importc.}
 
-proc quicly_get_fist_timeout*(conn: ptr quicly_conn_t): int64
-                             {.cdecl, importc.}
+proc quicly_get_first_timeout*(conn: ptr quicly_conn_t): int64
+                              {.cdecl, importc.}
diff --git a/quicly/streambuf.nim b/quicly/streambuf.nim
index 9573e8d..fd09b63 100644
--- a/quicly/streambuf.nim
+++ b/quicly/streambuf.nim
@@ -52,7 +52,7 @@ proc quicly_streambuf_ingress_receive*(stream: ptr quicly_stream_t,
                                       {.cdecl, importc.}
 
 proc quicly_streambuf_ingress_get*(stream: ptr quicly_stream_t): ptls_iovec_t
-                                  {.cdecl, importc.}
+                                  {.cdecl, importc, header: "quicly/streambuf.h".}
 
 proc quicly_streambuf_ingress_shift*(stream: ptr quicly_stream_t,
                                      delta: csize_t)