diff --git a/libp2p/chronosstream.nim b/libp2p/chronosstream.nim
index d251a7377..8cf992106 100644
--- a/libp2p/chronosstream.nim
+++ b/libp2p/chronosstream.nim
@@ -25,36 +25,36 @@ proc newChronosStream*(server: StreamServer,
   result.writer = newAsyncStreamWriter(client)
   result.closed = false
 
-method read*(s: ChronosStream, n = -1): Future[seq[byte]] {.async.} = 
+method read*(s: ChronosStream, n = -1): Future[seq[byte]] {.async, gcsafe.} = 
   result = await s.reader.read(n)
 
 method readExactly*(s: ChronosStream, 
                     pbytes: pointer, 
-                    nbytes: int): Future[void] {.async.} =
+                    nbytes: int): Future[void] {.async, gcsafe.} =
   await s.reader.readExactly(pbytes, nbytes)
 
-method readLine*(s: ChronosStream, limit = 0, sep = "\r\n"): Future[string] {.async.} =
+method readLine*(s: ChronosStream, limit = 0, sep = "\r\n"): Future[string] {.async, gcsafe.} =
   result = await s.reader.readLine(limit, sep)
 
-method readOnce*(s: ChronosStream, pbytes: pointer, nbytes: int): Future[int] {.async.} =
+method readOnce*(s: ChronosStream, pbytes: pointer, nbytes: int): Future[int] {.async, gcsafe.} =
   result = await s.reader.readOnce(pbytes, nbytes)
 
 method readUntil*(s: ChronosStream, 
                   pbytes: pointer, 
                   nbytes: int, 
-                  sep: seq[byte]): Future[int] {.async.} =
+                  sep: seq[byte]): Future[int] {.async, gcsafe.} =
   result = await s.reader.readUntil(pbytes, nbytes, sep)
 
-method write*(s: ChronosStream, pbytes: pointer, nbytes: int) {.async.} =
+method write*(s: ChronosStream, pbytes: pointer, nbytes: int) {.async, gcsafe.} =
   await s.writer.write(pbytes, nbytes)
 
-method write*(s: ChronosStream, msg: string, msglen = -1) {.async.} =
+method write*(s: ChronosStream, msg: string, msglen = -1) {.async, gcsafe.} =
   await s.writer.write(msg, msglen)
 
-method write*(s: ChronosStream, msg: seq[byte], msglen = -1) {.async.} =
+method write*(s: ChronosStream, msg: seq[byte], msglen = -1) {.async, gcsafe.} =
   await s.writer.write(msg, msglen)
 
-method close*(s: ChronosStream) {.async.} =
+method close*(s: ChronosStream) {.async, gcsafe.} =
   await s.reader.closeWait()
 
   await s.writer.finish()
diff --git a/libp2p/connection.nim b/libp2p/connection.nim
index 7365f9fa3..cbe183f59 100644
--- a/libp2p/connection.nim
+++ b/libp2p/connection.nim
@@ -22,44 +22,44 @@ proc newConnection*(stream: LPStream): Connection =
   new result
   result.stream = stream
 
-method read*(s: Connection, n = -1): Future[seq[byte]] {.async.} =
+method read*(s: Connection, n = -1): Future[seq[byte]] {.async, gcsafe.} =
   result = await s.stream.read(n)
 
 method readExactly*(s: Connection,
                     pbytes: pointer,
-                    nbytes: int): Future[void] {.async.} =
+                    nbytes: int): Future[void] {.async, gcsafe.} =
   await s.stream.readExactly(pbytes, nbytes)
 
 method readLine*(s: Connection,
                  limit = 0,
-                 sep = "\r\n"): Future[string] {.async.} =
+                 sep = "\r\n"): Future[string] {.async, gcsafe.} =
   result = await s.stream.readLine(limit, sep)
 
 method readOnce*(s: Connection,
                  pbytes: pointer,
-                 nbytes: int): Future[int] {.async.} =
+                 nbytes: int): Future[int] {.async, gcsafe.} =
   result = await s.stream.readOnce(pbytes, nbytes)
 
 method readUntil*(s: Connection,
                   pbytes: pointer,
                   nbytes: int,
-                  sep: seq[byte]): Future[int] {.async.} =
+                  sep: seq[byte]): Future[int] {.async, gcsafe.} =
   result = await s.stream.readUntil(pbytes, nbytes, sep)
 
-method write*(s: Connection, pbytes: pointer, nbytes: int) {.async.} =
+method write*(s: Connection, pbytes: pointer, nbytes: int) {.async, gcsafe.} =
   await s.stream.write(pbytes, nbytes)
 
-method write*(s: Connection, msg: string, msglen = -1) {.async.} =
+method write*(s: Connection, msg: string, msglen = -1) {.async, gcsafe.} =
   await s.stream.write(msg, msglen)
 
-method write*(s: Connection, msg: seq[byte], msglen = -1) {.async.} =
+method write*(s: Connection, msg: seq[byte], msglen = -1) {.async, gcsafe.} =
   await s.stream.write(msg, msglen)
 
-method close*(s: Connection) {.async.} =
+method close*(s: Connection) {.async, gcsafe.} =
   await s.stream.close()
   s.closed = true
 
-proc readLp*(s: Connection): Future[seq[byte]] {.async.} =
+proc readLp*(s: Connection): Future[seq[byte]] {.async, gcsafe.} =
   ## read lenght prefixed msg
   var
     size: uint
@@ -81,18 +81,18 @@ proc readLp*(s: Connection): Future[seq[byte]] {.async.} =
 
   result = buffer
 
-proc writeLp*(s: Connection, msg: string | seq[byte]) {.async.} =
+proc writeLp*(s: Connection, msg: string | seq[byte]) {.async, gcsafe.} =
   ## write lenght prefixed
   var buf = initVBuffer()
   buf.writeSeq(msg)
   buf.finish()
   result = s.write(buf.buffer)
 
-method getPeerInfo*(c: Connection): Future[PeerInfo] {.base, async.} =
+method getPeerInfo*(c: Connection): Future[PeerInfo] {.base, async, gcsafe.} =
   ## get up to date peer info
   ## TODO: implement PeerInfo refresh over identify
   discard
 
-method getObservedAddrs*(c: Connection): Future[MultiAddress] {.base, async.} =
+method getObservedAddrs*(c: Connection): Future[MultiAddress] {.base, async, gcsafe.} =
   ## get resolved multiaddresses for the connection
   discard
diff --git a/libp2p/identify.nim b/libp2p/identify.nim
index 2de518566..db8ef7416 100644
--- a/libp2p/identify.nim
+++ b/libp2p/identify.nim
@@ -17,6 +17,8 @@ const IdentifyPushCodec* = "/ipfs/id/push/1.0.0"
 const ProtoVersion* = "ipfs/0.1.0"
 const AgentVersion* = "nim-libp2p/0.0.1"
 
+#TODO: implment push identify, leaving out for now as it is not essential
+
 type
   # TODO: we're doing protobuf manualy, this is only temporary
   ProtoField[T] = object
diff --git a/libp2p/stream.nim b/libp2p/stream.nim
index e5f65443f..64e84a63c 100644
--- a/libp2p/stream.nim
+++ b/libp2p/stream.nim
@@ -13,39 +13,39 @@ type LPStream* = ref object of RootObj
   closed*: bool
 
 method read*(s: LPStream, n = -1): Future[seq[byte]]
-  {.base, async.} =
+  {.base, async, gcsafe.} =
   discard
 
 method readExactly*(s: LPStream, pbytes: pointer, nbytes: int): Future[void]
-  {.base, async.} =
+  {.base, async, gcsafe.} =
   discard
 
 method readLine*(s: LPStream, limit = 0, sep = "\r\n"): Future[string]
-  {.base, async.} =
+  {.base, async, gcsafe.} =
   discard
 
 method readOnce*(s: LPStream, pbytes: pointer, nbytes: int): Future[int]
-  {.base, async.} =
+  {.base, async, gcsafe.} =
   discard
 
 method readUntil*(s: LPStream,
                   pbytes: pointer, nbytes: int,
                   sep: seq[byte]): Future[int]
-  {.base, async.} =
+  {.base, async, gcsafe.} =
   discard
 
 method write*(s: LPStream, pbytes: pointer, nbytes: int)
-  {.base, async.} =
+  {.base, async, gcsafe.} =
   discard
 
 method write*(s: LPStream, msg: string, msglen = -1)
-  {.base, async.} =
+  {.base, async, gcsafe.} =
   discard
 
 method write*(s: LPStream, msg: seq[byte], msglen = -1)
-  {.base, async.} =
+  {.base, async, gcsafe.} =
   discard
 
 method close*(s: LPStream)
-  {.base, async.} =
+  {.base, async, gcsafe.} =
   discard
diff --git a/libp2p/tcptransport.nim b/libp2p/tcptransport.nim
index 46a6c0418..63d687fdb 100644
--- a/libp2p/tcptransport.nim
+++ b/libp2p/tcptransport.nim
@@ -18,7 +18,7 @@ type TcpTransport* = ref object of Transport
 proc connHandler*(t: Transport,
                   server: StreamServer,
                   client: StreamTransport): Future[Connection]
-                  {.gcsafe, async.} =
+                  {.async, gcsafe.} =
   let conn: Connection = newConnection(newChronosStream(server, client))
   let handlerFut = if t.handler == nil: nil else: t.handler(conn)
   let connHolder: ConnHolder = ConnHolder(connection: conn,
@@ -27,14 +27,14 @@ proc connHandler*(t: Transport,
   result = conn
 
 proc connCb(server: StreamServer,
-            client: StreamTransport) {.gcsafe, async.} =
+            client: StreamTransport) {.async, gcsafe.} =
   let t: Transport = cast[Transport](server.udata)
   discard t.connHandler(server, client)
 
 method init*(t: TcpTransport) =
   t.multicodec = multiCodec("tcp")
 
-method close*(t: TcpTransport): Future[void] {.async.} =
+method close*(t: TcpTransport): Future[void] {.async, gcsafe.} =
   ## start the transport
   await procCall Transport(t).close() # call base
 
@@ -43,7 +43,7 @@ method close*(t: TcpTransport): Future[void] {.async.} =
 
 method listen*(t: TcpTransport,
                ma: MultiAddress,
-               handler: ConnHandler): Future[void] {.async.} =
+               handler: ConnHandler): Future[void] {.async, gcsafe.} =
   await procCall Transport(t).listen(ma, handler) # call base
 
   ## listen on the transport
@@ -56,9 +56,9 @@ method listen*(t: TcpTransport,
   listenFuture.complete()
 
 method dial*(t: TcpTransport,
-             address: MultiAddress): Future[Connection] {.async.} =
+             address: MultiAddress): Future[Connection] {.async, gcsafe.} =
   ## dial a peer
   let client: StreamTransport = await connect(address)
   result = await t.connHandler(t.server, client)
 
-method handles*(t: Transport, address: MultiAddress): bool = true
+method handles*(t: Transport, address: MultiAddress): bool {.gcsafe.} = true
diff --git a/libp2p/transport.nim b/libp2p/transport.nim
index 1b595e31c..abc523429 100644
--- a/libp2p/transport.nim
+++ b/libp2p/transport.nim
@@ -23,15 +23,15 @@ type
     handler*: ConnHandler
     multicodec*: MultiCodec
 
-method init*(t: Transport) {.base.} =
+method init*(t: Transport) {.base, gcsafe.} =
   ## perform protocol initialization
   discard
 
-proc newTransport*(t: typedesc[Transport]): t =
+proc newTransport*(t: typedesc[Transport]): t {.gcsafe.} =
   new result
   result.init()
 
-method close*(t: Transport) {.base, async.} =
+method close*(t: Transport) {.base, async, gcsafe.} =
   ## stop and cleanup the transport
   ## including all outstanding connections
   for c in t.connections:
@@ -39,17 +39,18 @@ method close*(t: Transport) {.base, async.} =
 
 method listen*(t: Transport,
                ma: MultiAddress,
-               handler: ConnHandler) {.base, async.} =
+               handler: ConnHandler) {.base, async, gcsafe.} =
   ## listen for incoming connections
   t.ma = ma
   t.handler = handler
 
 method dial*(t: Transport,
-             address: MultiAddress): Future[Connection] {.base, async.} =
+             address: MultiAddress): 
+             Future[Connection] {.base, async, gcsafe.} =
   ## dial a peer
   discard
 
-method handles*(t: Transport, address: MultiAddress): bool {.base.} =
+method handles*(t: Transport, address: MultiAddress): bool {.base, gcsafe.} =
   ## check if transport supportes the multiaddress
   # TODO: this should implement generic logic that would use the multicodec 
   # declared in the multicodec field and set by each individual transport
diff --git a/tests/testidentify.nim b/tests/testidentify.nim
index eb3345be0..78208e6f7 100644
--- a/tests/testidentify.nim
+++ b/tests/testidentify.nim
@@ -1,9 +1,11 @@
 import unittest
 import chronos, strutils, sequtils
 import ../libp2p/identify, ../libp2p/multiaddress, 
-       ../libp2p/peerinfo, ../libp2p/peer, ../libp2p/connection, 
-       ../libp2p/identify, ../libp2p/multistream, ../libp2p/transport,
-       ../libp2p/tcptransport, ../libp2p/protocol, ../libp2p/crypto/crypto
+       ../libp2p/peerinfo, ../libp2p/peer, 
+       ../libp2p/connection, ../libp2p/identify, 
+       ../libp2p/multistream, ../libp2p/transport,
+       ../libp2p/tcptransport, ../libp2p/protocol, 
+       ../libp2p/crypto/crypto
 
 suite "Identify":
   test "handle identify message6":
diff --git a/tests/testtransport.nim b/tests/testtransport.nim
index c54133c77..1084975ba 100644
--- a/tests/testtransport.nim
+++ b/tests/testtransport.nim
@@ -5,7 +5,7 @@ import ../libp2p/connection, ../libp2p/transport, ../libp2p/tcptransport,
 
 suite "TCP transport suite":
   test "test listener: handle write":
-    proc testListener(): Future[bool] {.async.} =
+    proc testListener(): Future[bool] {.async, gcsafe.} =
       let ma: MultiAddress = Multiaddress.init("/ip4/127.0.0.1/tcp/53335")
       proc connHandler(conn: Connection): Future[void] {.async, gcsafe.} =
         result = conn.write(cstring("Hello!"), 6)
@@ -41,7 +41,7 @@ suite "TCP transport suite":
   test "test dialer: handle write":
     proc testDialer(address: TransportAddress): Future[bool] {.async.} =
       proc serveClient(server: StreamServer,
-                       transp: StreamTransport) {.async.} =
+                       transp: StreamTransport) {.async, gcsafe.} =
         var wstream = newAsyncStreamWriter(transp)
         await wstream.write("Hello!")
         await wstream.finish()
@@ -65,9 +65,9 @@ suite "TCP transport suite":
     check waitFor(testDialer(initTAddress("127.0.0.1:53337"))) == true
 
   test "test dialer: handle write":
-    proc testDialer(address: TransportAddress): Future[bool] {.async.} =
+    proc testDialer(address: TransportAddress): Future[bool] {.async, gcsafe.} =
       proc serveClient(server: StreamServer,
-                        transp: StreamTransport) {.async.} =
+                        transp: StreamTransport) {.async, gcsafe.} =
         var rstream = newAsyncStreamReader(transp)
         let msg = await rstream.read(6)
         check cast[string](msg) == "Hello!"