diff --git a/libp2p/muxers/mplex/mplex.nim b/libp2p/muxers/mplex/mplex.nim
index 5f27acc80..e16913d54 100644
--- a/libp2p/muxers/mplex/mplex.nim
+++ b/libp2p/muxers/mplex/mplex.nim
@@ -7,12 +7,14 @@
 ## This file may not be copied, modified, or distributed except according to
 ## those terms.
 
-## TODO: I have to be carefull to clean up channels correctly
+## TODO: I have to be carefull to clean up channels correctly,
 ## both by removing them from the internal tables as well as
-## cleaning up when the channel is completelly finished, this
-## is complicated because half closed makes it non-deterministic.
-## This still needs to be implemented properly - I'm leaving it here
-## to not forget that this needs to be fixed ASAP.
+## cleaning up when the channel is completelly finished. This
+## is complicated because half-closed streams makes closing 
+## channels non non-deterministic. 
+## 
+## This still needs to be implemented properly - I'm leaving it 
+## here to not forget that this needs to be fixed ASAP.
 
 import tables, sequtils
 import chronos
@@ -28,7 +30,6 @@ type
     local*: Table[int, Channel]
     currentId*: int
     maxChannels*: uint
-    streamHandler*: StreamHandler
 
 proc newMplexUnknownMsgError(): ref MplexUnknownMsgError =
   result = newException(MplexUnknownMsgError, "Unknown mplex message type")
@@ -59,7 +60,8 @@ method handle*(m: Mplex): Future[void] {.async, gcsafe.} =
       case msgType:
         of MessageType.New:
           let channel = await m.newStreamInternal(false, id.int)
-          channel.handlerFuture = m.streamHandler(newConnection(channel))
+          if not isNil(m.streamHandler):
+            channel.handlerFuture = m.streamHandler(newConnection(channel))
         of MessageType.MsgIn, MessageType.MsgOut:
           let channel = m.getChannelList(initiator)[id.int]
           let msg = await m.connection.readLp()
@@ -79,12 +81,10 @@ method handle*(m: Mplex): Future[void] {.async, gcsafe.} =
     await m.connection.close()
 
 proc newMplex*(conn: Connection, 
-               streamHandler: StreamHandler, 
                maxChanns: uint = MaxChannels): Mplex =
   new result
   result.connection = conn
   result.maxChannels = maxChanns
-  result.streamHandler = streamHandler
   result.remote = initTable[int, Channel]()
   result.local = initTable[int, Channel]()
 
diff --git a/libp2p/muxers/mplex/types.nim b/libp2p/muxers/mplex/types.nim
index fe29a82ae..f83bb37a7 100644
--- a/libp2p/muxers/mplex/types.nim
+++ b/libp2p/muxers/mplex/types.nim
@@ -25,5 +25,3 @@ type
     CloseOut,
     ResetIn,
     ResetOut
-
-  StreamHandler* = proc(conn: Connection): Future[void] {.gcsafe.}
diff --git a/libp2p/muxers/muxer.nim b/libp2p/muxers/muxer.nim
index 5623169a2..03d5dcfce 100644
--- a/libp2p/muxers/muxer.nim
+++ b/libp2p/muxers/muxer.nim
@@ -11,7 +11,10 @@ import chronos
 import ../protocol, ../connection
 
 type
+  StreamHandler* = proc(conn: Connection): Future[void] {.gcsafe.}
+
   Muxer* = ref object of RootObj
+    streamHandler*: StreamHandler
     connection*: Connection
 
   MuxerCreator* = proc(conn: Connection): Muxer {.gcsafe, closure.}
@@ -33,3 +36,6 @@ method init(c: MuxerProvider) =
 method newStream*(m: Muxer): Future[Connection] {.base, async, gcsafe.} = discard
 method close*(m: Muxer) {.base, async, gcsafe.} = discard
 method handle*(m: Muxer): Future[void] {.base, async, gcsafe.} = discard
+
+method `=streamHandler`*(m: Muxer, handler: StreamHandler) {.base, gcsafe.} = 
+  m.streamHandler = handler
diff --git a/tests/testmplex.nim b/tests/testmplex.nim
index 6a2fbe922..56de312fe 100644
--- a/tests/testmplex.nim
+++ b/tests/testmplex.nim
@@ -79,7 +79,8 @@ suite "Mplex":
           await stream.writeLp("Hello from stream!")
           await stream.close()
 
-        let mplexListen = newMplex(conn, handleMplexListen)
+        let mplexListen = newMplex(conn)
+        mplexListen.streamHandler = handleMplexListen
         await mplexListen.handle()
 
       let transport1: TcpTransport = newTransport(TcpTransport)
@@ -88,8 +89,7 @@ suite "Mplex":
       let transport2: TcpTransport = newTransport(TcpTransport)
       let conn = await transport2.dial(ma)
 
-      proc handleDial(stream: Connection) {.async, gcsafe.} = discard
-      let mplexDial = newMplex(conn, handleDial)
+      let mplexDial = newMplex(conn)
       let dialFut = mplexDial.handle()
       let stream  = await mplexDial.newStream()
       check cast[string](await stream.readLp()) == "Hello from stream!"
@@ -110,7 +110,8 @@ suite "Mplex":
           check cast[string](msg) == "Hello from stream!"
           await stream.close()
 
-        let mplexListen = newMplex(conn, handleMplexListen)
+        let mplexListen = newMplex(conn)
+        mplexListen.streamHandler = handleMplexListen
         await mplexListen.handle()
 
       let transport1: TcpTransport = newTransport(TcpTransport)
@@ -119,8 +120,7 @@ suite "Mplex":
       let transport2: TcpTransport = newTransport(TcpTransport)
       let conn = await transport2.dial(ma)
 
-      proc handleDial(stream: Connection) {.async, gcsafe.} = discard
-      let mplexDial = newMplex(conn, handleDial)
+      let mplexDial = newMplex(conn)
       let dialFut = mplexDial.handle()
       let stream  = await mplexDial.newStream()
       await stream.writeLp("Hello from stream!")