diff --git a/chronos/unittest2/asynctests.nim b/chronos/unittest2/asynctests.nim
index bc703b7..758e0a6 100644
--- a/chronos/unittest2/asynctests.nim
+++ b/chronos/unittest2/asynctests.nim
@@ -21,9 +21,9 @@ template asyncTest*(name: string, body: untyped): untyped =
 
 template checkLeaks*(name: string): untyped =
   let counter = getTrackerCounter(name)
-  if counter.opened != counter.closed:
-    echo "[" & name & "] opened = ", counter.opened,
-         ", closed = ", counter.closed
+  checkpoint:
+    "[" & name & "] opened = " & $counter.opened &
+         ", closed = " & $ counter.closed
   check counter.opened == counter.closed
 
 template checkLeaks*(): untyped =
diff --git a/tests/testserver.nim b/tests/testserver.nim
index e7e834e..a63c9df 100644
--- a/tests/testserver.nim
+++ b/tests/testserver.nim
@@ -5,8 +5,8 @@
 #              Licensed under either of
 #  Apache License, version 2.0, (LICENSE-APACHEv2)
 #              MIT license (LICENSE-MIT)
-import unittest2
-import ../chronos
+
+import ../chronos/unittest2/asynctests
 
 {.used.}
 
@@ -23,6 +23,9 @@ suite "Server's test suite":
     CustomData = ref object
       test: string
 
+  teardown:
+    checkLeaks()
+
   proc serveStreamClient(server: StreamServer,
                          transp: StreamTransport) {.async.} =
     discard
@@ -54,37 +57,47 @@ suite "Server's test suite":
     transp.test = "CUSTOM"
     result = cast[StreamTransport](transp)
 
-  proc test1(): bool =
+  asyncTest "Stream Server start/stop test":
     var ta = initTAddress("127.0.0.1:31354")
     var server1 = createStreamServer(ta, serveStreamClient, {ReuseAddr})
     server1.start()
     server1.stop()
     server1.close()
-    waitFor server1.join()
+    await server1.join()
+
     var server2 = createStreamServer(ta, serveStreamClient, {ReuseAddr})
     server2.start()
     server2.stop()
     server2.close()
-    waitFor server2.join()
-    result = true
+    await server2.join()
 
-  proc test5(): bool =
-    var ta = initTAddress("127.0.0.1:31354")
+  asyncTest "Stream Server stop without start test":
+    var ta = initTAddress("127.0.0.1:0")
     var server1 = createStreamServer(ta, serveStreamClient, {ReuseAddr})
+    ta = server1.localAddress()
     server1.stop()
     server1.close()
-    waitFor server1.join()
+
+    await server1.join()
     var server2 = createStreamServer(ta, serveStreamClient, {ReuseAddr})
     server2.stop()
     server2.close()
-    waitFor server2.join()
-    result = true
+    await server2.join()
+
+  asyncTest "Stream Server inherited object test":
+    var server = CustomServer()
+    server.test1 = "TEST"
+    var ta = initTAddress("127.0.0.1:0")
+    var pserver = createStreamServer(ta, serveCustomStreamClient, {ReuseAddr},
+                                     child = server,
+                                     init = customServerTransport)
+    check:
+      pserver == server
 
-  proc client1(server: CustomServer, ta: TransportAddress) {.async.} =
     var transp = CustomTransport()
     transp.test = "CLIENT"
     server.start()
-    var ptransp = await connect(ta, child = transp)
+    var ptransp = await connect(server.localAddress(), child = transp)
     var etransp = cast[CustomTransport](ptransp)
     doAssert(etransp.test == "CLIENT")
     var msg = "TEST\r\n"
@@ -96,44 +109,48 @@ suite "Server's test suite":
     server.close()
     await server.join()
 
-  proc client2(server: StreamServer,
-               ta: TransportAddress): Future[bool] {.async.} =
+    check:
+      server.test1 == "CONNECTION"
+      server.test2 == "CUSTOM"
+
+  asyncTest "StreamServer[T] test":
+    var co = CustomData()
+    co.test = "CUSTOMDATA"
+    var ta = initTAddress("127.0.0.1:0")
+    var server = createStreamServer(ta, serveUdataStreamClient, {ReuseAddr},
+                                    udata = co)
+
     server.start()
-    var transp = await connect(ta)
+    var transp = await connect(server.localAddress())
     var msg = "TEST\r\n"
     discard await transp.write(msg)
     var line = await transp.readLine()
-    result = (line == "TESTCUSTOMDATA")
+    check:
+      line == "TESTCUSTOMDATA"
     transp.close()
     server.stop()
     server.close()
     await server.join()
 
-  proc test3(): bool =
-    var server = CustomServer()
-    server.test1 = "TEST"
-    var ta = initTAddress("127.0.0.1:31354")
-    var pserver = createStreamServer(ta, serveCustomStreamClient, {ReuseAddr},
-                                     child = cast[StreamServer](server),
-                                     init = customServerTransport)
-    doAssert(not isNil(pserver))
-    waitFor client1(server, ta)
-    result = (server.test1 == "CONNECTION") and (server.test2 == "CUSTOM")
+  asyncTest "Backlog and connect cancellation":
+    var ta = initTAddress("127.0.0.1:0")
+    var server1 = createStreamServer(ta, serveStreamClient, {ReuseAddr}, backlog = 1)
+    ta = server1.localAddress()
 
-  proc test4(): bool =
-    var co = CustomData()
-    co.test = "CUSTOMDATA"
-    var ta = initTAddress("127.0.0.1:31354")
-    var server = createStreamServer(ta, serveUdataStreamClient, {ReuseAddr},
-                                    udata = co)
-    result = waitFor client2(server, ta)
+    var clients: seq[Future[StreamTransport]]
+    for i in 0..<10:
+      clients.add(connect(server1.localAddress))
 
+    # Check for leaks in cancellation / connect when server is not accepting
+    for c in clients:
+      if not c.finished:
+        await c.cancelAndWait()
+      else:
+        # The backlog connection "should" end up here
+        try:
+          await c.read().closeWait()
+        except CatchableError:
+          discard
 
-  test "Stream Server start/stop test":
-    check test1() == true
-  test "Stream Server stop without start test":
-    check test5() == true
-  test "Stream Server inherited object test":
-    check test3() == true
-  test "StreamServer[T] test":
-    check test4() == true
+    server1.close()
+    await server1.join()