diff --git a/core/Cargo.toml b/core/Cargo.toml
index c2b85f01..4f039c35 100644
--- a/core/Cargo.toml
+++ b/core/Cargo.toml
@@ -48,10 +48,8 @@ libp2p-mplex = { version = "0.12.0", path = "../muxers/mplex" }
 libp2p-secio = { version = "0.12.0", path = "../protocols/secio" }
 rand = "0.6"
 quickcheck = "0.8"
-tokio = "0.1"
-wasm-timer = "0.1"
+wasm-timer = "0.2"
 assert_matches = "1.3"
-tokio-mock-task = "0.1"
 
 [features]
 default = ["secp256k1"]
diff --git a/core/src/nodes/listeners.rs b/core/src/nodes/listeners.rs
index b9c8ebbf..861f3e75 100644
--- a/core/src/nodes/listeners.rs
+++ b/core/src/nodes/listeners.rs
@@ -51,32 +51,30 @@ use std::{collections::VecDeque, fmt, pin::Pin};
 /// listeners.listen_on("/ip4/0.0.0.0/tcp/0".parse().unwrap()).unwrap();
 ///
 /// // The `listeners` will now generate events when polled.
-/// let future = listeners.for_each(move |event| {
-///     match event {
-///         ListenersEvent::NewAddress { listener_id, listen_addr } => {
-///             println!("Listener {:?} is listening at address {}", listener_id, listen_addr);
-///         },
-///         ListenersEvent::AddressExpired { listener_id, listen_addr } => {
-///             println!("Listener {:?} is no longer listening at address {}", listener_id, listen_addr);
-///         },
-///         ListenersEvent::Closed { listener_id, .. } => {
-///             println!("Listener {:?} has been closed", listener_id);
-///         },
-///         ListenersEvent::Error { listener_id, error } => {
-///             println!("Listener {:?} has experienced an error: {}", listener_id, error);
-///         },
-///         ListenersEvent::Incoming { listener_id, upgrade, local_addr, .. } => {
-///             println!("Listener {:?} has a new connection on {}", listener_id, local_addr);
-///             // We don't do anything with the newly-opened connection, but in a real-life
-///             // program you probably want to use it!
-///             drop(upgrade);
-///         },
-///     };
-///
-///     Ok(())
-/// });
-///
-/// tokio::run(future.map_err(|_| ()));
+/// futures::executor::block_on(async move {
+///     while let Some(event) = listeners.next().await {
+///         match event {
+///             ListenersEvent::NewAddress { listener_id, listen_addr } => {
+///                 println!("Listener {:?} is listening at address {}", listener_id, listen_addr);
+///             },
+///             ListenersEvent::AddressExpired { listener_id, listen_addr } => {
+///                 println!("Listener {:?} is no longer listening at address {}", listener_id, listen_addr);
+///             },
+///             ListenersEvent::Closed { listener_id, .. } => {
+///                 println!("Listener {:?} has been closed", listener_id);
+///             },
+///             ListenersEvent::Error { listener_id, error } => {
+///                 println!("Listener {:?} has experienced an error: {}", listener_id, error);
+///             },
+///             ListenersEvent::Incoming { listener_id, upgrade, local_addr, .. } => {
+///                 println!("Listener {:?} has a new connection on {}", listener_id, local_addr);
+///                 // We don't do anything with the newly-opened connection, but in a real-life
+///                 // program you probably want to use it!
+///                 drop(upgrade);
+///             },
+///         }
+///     }
+/// })
 /// # }
 /// ```
 pub struct ListenersStream<TTrans>
@@ -358,7 +356,6 @@ mod tests {
     use super::*;
     use crate::transport::{self, ListenerEvent};
     use assert_matches::assert_matches;
-    use tokio::runtime::current_thread::Runtime;
     use std::{io, iter::FromIterator};
     use futures::{future::{self}, stream};
     use crate::PeerId;
diff --git a/core/src/transport/memory.rs b/core/src/transport/memory.rs
index e53a1f2b..ad3312e6 100644
--- a/core/src/transport/memory.rs
+++ b/core/src/transport/memory.rs
@@ -19,7 +19,7 @@
 // DEALINGS IN THE SOFTWARE.
 
 use crate::{Transport, transport::{TransportError, ListenerEvent}};
-use bytes::{Bytes, IntoBuf};
+use bytes::IntoBuf;
 use fnv::FnvHashMap;
 use futures::{future::{self, Ready}, prelude::*, channel::mpsc, task::Context, task::Poll};
 use lazy_static::lazy_static;
@@ -29,7 +29,7 @@ use rw_stream_sink::RwStreamSink;
 use std::{collections::hash_map::Entry, error, fmt, io, num::NonZeroU64, pin::Pin};
 
 lazy_static! {
-    static ref HUB: Mutex<FnvHashMap<NonZeroU64, mpsc::Sender<Channel<Bytes>>>> =
+    static ref HUB: Mutex<FnvHashMap<NonZeroU64, mpsc::Sender<Channel<Vec<u8>>>>> =
         Mutex::new(FnvHashMap::default());
 }
 
@@ -39,13 +39,13 @@ pub struct MemoryTransport;
 
 /// Connection to a `MemoryTransport` currently being opened.
 pub struct DialFuture {
-    sender: mpsc::Sender<Channel<Bytes>>,
-    channel_to_send: Option<Channel<Bytes>>,
-    channel_to_return: Option<Channel<Bytes>>,
+    sender: mpsc::Sender<Channel<Vec<u8>>>,
+    channel_to_send: Option<Channel<Vec<u8>>>,
+    channel_to_return: Option<Channel<Vec<u8>>>,
 }
 
 impl Future for DialFuture {
-    type Output = Result<Channel<Bytes>, MemoryTransportError>;
+    type Output = Result<Channel<Vec<u8>>, MemoryTransportError>;
 
     fn poll(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> {
         match self.sender.poll_ready(cx) {
@@ -67,7 +67,7 @@ impl Future for DialFuture {
 }
 
 impl Transport for MemoryTransport {
-    type Output = Channel<Bytes>;
+    type Output = Channel<Vec<u8>>;
     type Error = MemoryTransportError;
     type Listener = Listener;
     type ListenerUpgrade = Ready<Result<Self::Output, Self::Error>>;
@@ -168,13 +168,13 @@ pub struct Listener {
     /// The address we are listening on.
     addr: Multiaddr,
     /// Receives incoming connections.
-    receiver: mpsc::Receiver<Channel<Bytes>>,
+    receiver: mpsc::Receiver<Channel<Vec<u8>>>,
     /// Generate `ListenerEvent::NewAddress` to inform about our listen address.
     tell_listen_addr: bool
 }
 
 impl Stream for Listener {
-    type Item = Result<ListenerEvent<Ready<Result<Channel<Bytes>, MemoryTransportError>>>, MemoryTransportError>;
+    type Item = Result<ListenerEvent<Ready<Result<Channel<Vec<u8>>, MemoryTransportError>>>, MemoryTransportError>;
 
     fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<Option<Self::Item>> {
         if self.tell_listen_addr {
@@ -230,7 +230,7 @@ pub type Channel<T> = RwStreamSink<Chan<T>>;
 /// A channel represents an established, in-memory, logical connection between two endpoints.
 ///
 /// Implements `Sink` and `Stream`.
-pub struct Chan<T = Bytes> {
+pub struct Chan<T = Vec<u8>> {
     incoming: mpsc::Receiver<T>,
     outgoing: mpsc::Sender<T>,
 }
diff --git a/core/tests/network_dial_error.rs b/core/tests/network_dial_error.rs
index e6ff2d2b..976ec980 100644
--- a/core/tests/network_dial_error.rs
+++ b/core/tests/network_dial_error.rs
@@ -34,7 +34,7 @@ use libp2p_swarm::{
     protocols_handler::NodeHandlerWrapperBuilder
 };
 use rand::seq::SliceRandom;
-use std::io;
+use std::{io, task::Context, task::Poll};
 
 // TODO: replace with DummyProtocolsHandler after https://github.com/servo/rust-smallvec/issues/139 ?
 struct TestHandler<TSubstream>(std::marker::PhantomData<TSubstream>);
@@ -47,7 +47,7 @@ impl<TSubstream> Default for TestHandler<TSubstream> {
 
 impl<TSubstream> ProtocolsHandler for TestHandler<TSubstream>
 where
-    TSubstream: futures::PollRead + futures::PollWrite
+    TSubstream: AsyncRead + AsyncWrite + Unpin + Send + 'static
 {
     type InEvent = ();      // TODO: cannot be Void (https://github.com/servo/rust-smallvec/issues/139)
     type OutEvent = ();      // TODO: cannot be Void (https://github.com/servo/rust-smallvec/issues/139)
@@ -82,7 +82,7 @@ where
 
     fn connection_keep_alive(&self) -> KeepAlive { KeepAlive::No }
 
-    fn poll(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<ProtocolsHandlerEvent<Self::OutboundProtocol, Self::OutboundOpenInfo, Self::OutEvent, Self::Error>, Self::Error> {
+    fn poll(&mut self, _: &mut Context) -> Poll<ProtocolsHandlerEvent<Self::OutboundProtocol, Self::OutboundOpenInfo, Self::OutEvent, Self::Error>> {
         Poll::Pending
     }
 }
@@ -113,26 +113,27 @@ fn deny_incoming_connec() {
 
     swarm1.listen_on("/ip4/127.0.0.1/tcp/0".parse().unwrap()).unwrap();
 
-    let address =
-        if let Poll::Ready(NetworkEvent::NewListenerAddress { listen_addr, .. }) = swarm1.poll() {
-            listen_addr
+    let address = futures::executor::block_on(future::poll_fn(|cx| {
+        if let Poll::Ready(NetworkEvent::NewListenerAddress { listen_addr, .. }) = swarm1.poll(cx) {
+            Poll::Ready(listen_addr)
         } else {
             panic!("Was expecting the listen address to be reported")
-        };
+        }
+    }));
 
     swarm2
         .peer(swarm1.local_peer_id().clone())
         .into_not_connected().unwrap()
         .connect(address.clone(), TestHandler::default().into_node_handler_builder());
 
-    let future = future::poll_fn(|| -> Poll<Result<(), io::Error>> {
-        match swarm1.poll() {
+    futures::executor::block_on(future::poll_fn(|cx| -> Poll<Result<(), io::Error>> {
+        match swarm1.poll(cx) {
             Poll::Ready(NetworkEvent::IncomingConnection(inc)) => drop(inc),
             Poll::Ready(_) => unreachable!(),
             Poll::Pending => (),
         }
 
-        match swarm2.poll() {
+        match swarm2.poll(cx) {
             Poll::Ready(NetworkEvent::DialError {
                 new_state: PeerState::NotConnected,
                 peer_id,
@@ -148,9 +149,7 @@ fn deny_incoming_connec() {
         }
 
         Poll::Pending
-    });
-
-    tokio::runtime::current_thread::Runtime::new().unwrap().block_on(future).unwrap();
+    })).unwrap();
 }
 
 #[test]
@@ -176,31 +175,30 @@ fn dial_self() {
             .and_then(|(peer, mplex), _| {
                 // Gracefully close the connection to allow protocol
                 // negotiation to complete.
-                util::CloseMuxer::new(mplex).map(move |mplex| (peer, mplex))
+                util::CloseMuxer::new(mplex).map_ok(move |mplex| (peer, mplex))
             });
         Network::new(transport, local_public_key.into())
     };
 
     swarm.listen_on("/ip4/127.0.0.1/tcp/0".parse().unwrap()).unwrap();
 
-    let (address, mut swarm) =
-        future::lazy(move || {
-            if let Poll::Ready(NetworkEvent::NewListenerAddress { listen_addr, .. }) = swarm.poll() {
+    let (address, mut swarm) = futures::executor::block_on(
+        future::lazy(move |cx| {
+            if let Poll::Ready(NetworkEvent::NewListenerAddress { listen_addr, .. }) = swarm.poll(cx) {
                 Ok::<_, void::Void>((listen_addr, swarm))
             } else {
                 panic!("Was expecting the listen address to be reported")
             }
-        })
-        .wait()
+        }))
         .unwrap();
 
     swarm.dial(address.clone(), TestHandler::default().into_node_handler_builder()).unwrap();
 
     let mut got_dial_err = false;
     let mut got_inc_err = false;
-    let future = future::poll_fn(|| -> Poll<Result<(), io::Error>> {
+    futures::executor::block_on(future::poll_fn(|cx| -> Poll<Result<(), io::Error>> {
         loop {
-            match swarm.poll() {
+            match swarm.poll(cx) {
                 Poll::Ready(NetworkEvent::UnknownPeerDialError {
                     multiaddr,
                     error: UnknownPeerDialErr::FoundLocalPeerId,
@@ -210,7 +208,7 @@ fn dial_self() {
                     assert!(!got_dial_err);
                     got_dial_err = true;
                     if got_inc_err {
-                        return Ok(Poll::Ready(()));
+                        return Poll::Ready(Ok(()));
                     }
                 },
                 Poll::Ready(NetworkEvent::IncomingConnectionError {
@@ -222,7 +220,7 @@ fn dial_self() {
                     assert!(!got_inc_err);
                     got_inc_err = true;
                     if got_dial_err {
-                        return Ok(Poll::Ready(()));
+                        return Poll::Ready(Ok(()));
                     }
                 },
                 Poll::Ready(NetworkEvent::IncomingConnection(inc)) => {
@@ -235,9 +233,7 @@ fn dial_self() {
                 Poll::Pending => break Poll::Pending,
             }
         }
-    });
-
-    tokio::runtime::current_thread::Runtime::new().unwrap().block_on(future).unwrap();
+    })).unwrap();
 }
 
 #[test]
@@ -288,9 +284,9 @@ fn multiple_addresses_err() {
         .connect_iter(addresses.clone(), TestHandler::default().into_node_handler_builder())
         .unwrap();
 
-    let future = future::poll_fn(|| -> Poll<Result<(), io::Error>> {
+    futures::executor::block_on(future::poll_fn(|cx| -> Poll<Result<(), io::Error>> {
         loop {
-            match swarm.poll() {
+            match swarm.poll(cx) {
                 Poll::Ready(NetworkEvent::DialError {
                     new_state,
                     peer_id,
@@ -302,7 +298,7 @@ fn multiple_addresses_err() {
                     assert_eq!(multiaddr, expected);
                     if addresses.is_empty() {
                         assert_eq!(new_state, PeerState::NotConnected);
-                        return Ok(Poll::Ready(()));
+                        return Poll::Ready(Ok(()));
                     } else {
                         match new_state {
                             PeerState::Dialing { num_pending_addresses } => {
@@ -316,7 +312,5 @@ fn multiple_addresses_err() {
                 Poll::Pending => break Poll::Pending,
             }
         }
-    });
-
-    tokio::runtime::current_thread::Runtime::new().unwrap().block_on(future).unwrap();
+    })).unwrap();
 }
diff --git a/core/tests/network_simult.rs b/core/tests/network_simult.rs
index 612875db..7d7a247a 100644
--- a/core/tests/network_simult.rs
+++ b/core/tests/network_simult.rs
@@ -31,8 +31,8 @@ use libp2p_swarm::{
     ProtocolsHandlerEvent,
     ProtocolsHandlerUpgrErr,
 };
-use std::{io, time::Duration};
-use wasm_timer::{Delay, Instant};
+use std::{io, pin::Pin, task::Context, task::Poll, time::Duration};
+use wasm_timer::Delay;
 
 // TODO: replace with DummyProtocolsHandler after https://github.com/servo/rust-smallvec/issues/139 ?
 struct TestHandler<TSubstream>(std::marker::PhantomData<TSubstream>);
@@ -45,7 +45,7 @@ impl<TSubstream> Default for TestHandler<TSubstream> {
 
 impl<TSubstream> ProtocolsHandler for TestHandler<TSubstream>
 where
-    TSubstream: futures::PollRead + futures::PollWrite
+    TSubstream: AsyncRead + AsyncWrite + Unpin + Send + 'static
 {
     type InEvent = ();      // TODO: cannot be Void (https://github.com/servo/rust-smallvec/issues/139)
     type OutEvent = ();      // TODO: cannot be Void (https://github.com/servo/rust-smallvec/issues/139)
@@ -80,7 +80,7 @@ where
 
     fn connection_keep_alive(&self) -> KeepAlive { KeepAlive::Yes }
 
-    fn poll(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<ProtocolsHandlerEvent<Self::OutboundProtocol, Self::OutboundOpenInfo, Self::OutEvent, Self::Error>, Self::Error> {
+    fn poll(&mut self, _: &mut Context) -> Poll<ProtocolsHandlerEvent<Self::OutboundProtocol, Self::OutboundOpenInfo, Self::OutEvent, Self::Error>> {
         Poll::Pending
     }
 }
@@ -116,7 +116,7 @@ fn raw_swarm_simultaneous_connect() {
                 .and_then(|(peer, mplex), _| {
                     // Gracefully close the connection to allow protocol
                     // negotiation to complete.
-                    util::CloseMuxer::new(mplex).map(move |mplex| (peer, mplex))
+                    util::CloseMuxer::new(mplex).map_ok(move |mplex| (peer, mplex))
                 });
             Network::new(transport, local_public_key.into_peer_id())
         };
@@ -131,7 +131,7 @@ fn raw_swarm_simultaneous_connect() {
                 .and_then(|(peer, mplex), _| {
                     // Gracefully close the connection to allow protocol
                     // negotiation to complete.
-                    util::CloseMuxer::new(mplex).map(move |mplex| (peer, mplex))
+                    util::CloseMuxer::new(mplex).map_ok(move |mplex| (peer, mplex))
                 });
             Network::new(transport, local_public_key.into_peer_id())
         };
@@ -139,17 +139,17 @@ fn raw_swarm_simultaneous_connect() {
         swarm1.listen_on("/ip4/127.0.0.1/tcp/0".parse().unwrap()).unwrap();
         swarm2.listen_on("/ip4/127.0.0.1/tcp/0".parse().unwrap()).unwrap();
 
-        let (swarm1_listen_addr, swarm2_listen_addr, mut swarm1, mut swarm2) =
-            future::lazy(move || {
+        let (swarm1_listen_addr, swarm2_listen_addr, mut swarm1, mut swarm2) = futures::executor::block_on(
+            future::lazy(move |cx| {
                 let swarm1_listen_addr =
-                    if let Poll::Ready(NetworkEvent::NewListenerAddress { listen_addr, .. }) = swarm1.poll() {
+                    if let Poll::Ready(NetworkEvent::NewListenerAddress { listen_addr, .. }) = swarm1.poll(cx) {
                         listen_addr
                     } else {
                         panic!("Was expecting the listen address to be reported")
                     };
 
                 let swarm2_listen_addr =
-                    if let Poll::Ready(NetworkEvent::NewListenerAddress { listen_addr, .. }) = swarm2.poll() {
+                    if let Poll::Ready(NetworkEvent::NewListenerAddress { listen_addr, .. }) = swarm2.poll(cx) {
                         listen_addr
                     } else {
                         panic!("Was expecting the listen address to be reported")
@@ -157,19 +157,16 @@ fn raw_swarm_simultaneous_connect() {
 
                 Ok::<_, void::Void>((swarm1_listen_addr, swarm2_listen_addr, swarm1, swarm2))
             })
-            .wait()
-            .unwrap();
-
-        let mut reactor = tokio::runtime::current_thread::Runtime::new().unwrap();
+        ).unwrap();
 
         loop {
             let mut swarm1_step = 0;
             let mut swarm2_step = 0;
 
-            let mut swarm1_dial_start = Delay::new(Instant::now() + Duration::new(0, rand::random::<u32>() % 50_000_000));
-            let mut swarm2_dial_start = Delay::new(Instant::now() + Duration::new(0, rand::random::<u32>() % 50_000_000));
+            let mut swarm1_dial_start = Delay::new(Duration::new(0, rand::random::<u32>() % 50_000_000));
+            let mut swarm2_dial_start = Delay::new(Duration::new(0, rand::random::<u32>() % 50_000_000));
 
-            let future = future::poll_fn(|| -> Poll<bool, io::Error> {
+            let future = future::poll_fn(|cx| -> Poll<bool> {
                 loop {
                     let mut swarm1_not_ready = false;
                     let mut swarm2_not_ready = false;
@@ -178,7 +175,7 @@ fn raw_swarm_simultaneous_connect() {
                     // handle other nodes, which may delay the processing.
 
                     if swarm1_step == 0 {
-                        match swarm1_dial_start.poll().unwrap() {
+                        match Future::poll(Pin::new(&mut swarm1_dial_start), cx) {
                             Poll::Ready(_) => {
                                 let handler = TestHandler::default().into_node_handler_builder();
                                 swarm1.peer(swarm2.local_peer_id().clone())
@@ -192,7 +189,7 @@ fn raw_swarm_simultaneous_connect() {
                     }
 
                     if swarm2_step == 0 {
-                        match swarm2_dial_start.poll().unwrap() {
+                        match Future::poll(Pin::new(&mut swarm2_dial_start), cx) {
                             Poll::Ready(_) => {
                                 let handler = TestHandler::default().into_node_handler_builder();
                                 swarm2.peer(swarm1.local_peer_id().clone())
@@ -206,7 +203,7 @@ fn raw_swarm_simultaneous_connect() {
                     }
 
                     if rand::random::<f32>() < 0.1 {
-                        match swarm1.poll() {
+                        match swarm1.poll(cx) {
                             Poll::Ready(NetworkEvent::IncomingConnectionError {
                                 error: IncomingError::DeniedLowerPriority, ..
                             }) => {
@@ -218,7 +215,7 @@ fn raw_swarm_simultaneous_connect() {
                                 if swarm1_step == 0 {
                                     // The connection was established before
                                     // swarm1 started dialing; discard the test run.
-                                    return Ok(Poll::Ready(false))
+                                    return Poll::Ready(false)
                                 }
                                 assert_eq!(swarm1_step, 1);
                                 swarm1_step = 2;
@@ -237,7 +234,7 @@ fn raw_swarm_simultaneous_connect() {
                     }
 
                     if rand::random::<f32>() < 0.1 {
-                        match swarm2.poll() {
+                        match swarm2.poll(cx) {
                             Poll::Ready(NetworkEvent::IncomingConnectionError {
                                 error: IncomingError::DeniedLowerPriority, ..
                             }) => {
@@ -249,7 +246,7 @@ fn raw_swarm_simultaneous_connect() {
                                 if swarm2_step == 0 {
                                     // The connection was established before
                                     // swarm2 started dialing; discard the test run.
-                                    return Ok(Poll::Ready(false))
+                                    return Poll::Ready(false)
                                 }
                                 assert_eq!(swarm2_step, 1);
                                 swarm2_step = 2;
@@ -269,7 +266,7 @@ fn raw_swarm_simultaneous_connect() {
 
                     // TODO: make sure that >= 5 is correct
                     if swarm1_step + swarm2_step >= 5 {
-                        return Ok(Poll::Ready(true));
+                        return Poll::Ready(true);
                     }
 
                     if swarm1_not_ready && swarm2_not_ready {
@@ -278,7 +275,7 @@ fn raw_swarm_simultaneous_connect() {
                 }
             });
 
-            if reactor.block_on(future).unwrap() {
+            if futures::executor::block_on(future) {
                 // The test exercised what we wanted to exercise: a simultaneous connect.
                 break
             } else {
diff --git a/core/tests/transport_upgrade.rs b/core/tests/transport_upgrade.rs
index 8ac012da..bee0c8d7 100644
--- a/core/tests/transport_upgrade.rs
+++ b/core/tests/transport_upgrade.rs
@@ -22,13 +22,13 @@ mod util;
 
 use futures::prelude::*;
 use libp2p_core::identity;
-use libp2p_core::transport::{Transport, MemoryTransport, ListenerEvent};
+use libp2p_core::transport::{Transport, MemoryTransport};
 use libp2p_core::upgrade::{self, UpgradeInfo, Negotiated, InboundUpgrade, OutboundUpgrade};
 use libp2p_mplex::MplexConfig;
 use libp2p_secio::SecioConfig;
 use multiaddr::Multiaddr;
 use rand::random;
-use std::io;
+use std::{io, pin::Pin};
 
 #[derive(Clone)]
 struct HelloUpgrade {}
@@ -44,30 +44,36 @@ impl UpgradeInfo for HelloUpgrade {
 
 impl<C> InboundUpgrade<C> for HelloUpgrade
 where
-    C: AsyncRead + AsyncWrite + Send + 'static
+    C: AsyncRead + AsyncWrite + Send + Unpin + 'static
 {
     type Output = Negotiated<C>;
     type Error = io::Error;
-    type Future = Box<dyn Future<Item = Self::Output, Error = Self::Error> + Send>;
+    type Future = Pin<Box<dyn Future<Output = Result<Self::Output, Self::Error>> + Send>>;
 
-    fn upgrade_inbound(self, socket: Negotiated<C>, _: Self::Info) -> Self::Future {
-        Box::new(nio::read_exact(socket, [0u8; 5]).map(|(io, buf)| {
+    fn upgrade_inbound(self, mut socket: Negotiated<C>, _: Self::Info) -> Self::Future {
+        Box::pin(async move {
+            let mut buf = [0u8; 5];
+            socket.read_exact(&mut buf).await.unwrap();
             assert_eq!(&buf[..], "hello".as_bytes());
-            io
-        }))
+            Ok(socket)
+        })
     }
 }
 
 impl<C> OutboundUpgrade<C> for HelloUpgrade
 where
-    C: AsyncWrite + AsyncRead + Send + 'static,
+    C: AsyncWrite + AsyncRead + Send + Unpin + 'static,
 {
     type Output = Negotiated<C>;
     type Error = io::Error;
-    type Future = Box<dyn Future<Item = Self::Output, Error = Self::Error> + Send>;
+    type Future = Pin<Box<dyn Future<Output = Result<Self::Output, Self::Error>> + Send>>;
 
-    fn upgrade_outbound(self, socket: Negotiated<C>, _: Self::Info) -> Self::Future {
-        Box::new(nio::write_all(socket, "hello").map(|(io, _)| io))
+    fn upgrade_outbound(self, mut socket: Negotiated<C>, _: Self::Info) -> Self::Future {
+        Box::pin(async move {
+            socket.write_all(b"hello").await.unwrap();
+            socket.flush().await.unwrap();
+            Ok(socket)
+        })
     }
 }
 
@@ -85,7 +91,7 @@ fn upgrade_pipeline() {
         .and_then(|(peer, mplex), _| {
             // Gracefully close the connection to allow protocol
             // negotiation to complete.
-            util::CloseMuxer::new(mplex).map(move |mplex| (peer, mplex))
+            util::CloseMuxer::new(mplex).map_ok(move |mplex| (peer, mplex))
         });
 
     let dialer_keys = identity::Keypair::generate_ed25519();
@@ -100,27 +106,31 @@ fn upgrade_pipeline() {
         .and_then(|(peer, mplex), _| {
             // Gracefully close the connection to allow protocol
             // negotiation to complete.
-            util::CloseMuxer::new(mplex).map(move |mplex| (peer, mplex))
+            util::CloseMuxer::new(mplex).map_ok(move |mplex| (peer, mplex))
         });
 
     let listen_addr: Multiaddr = format!("/memory/{}", random::<u64>()).parse().unwrap();
-    let listener = listener_transport.listen_on(listen_addr.clone()).unwrap()
-        .filter_map(ListenerEvent::into_upgrade)
-        .for_each(move |(upgrade, _remote_addr)| {
-            let dialer = dialer_id.clone();
-            upgrade.map(move |(peer, _mplex)| {
-                assert_eq!(peer, dialer)
-            })
-        })
-        .map_err(|e| panic!("Listener error: {}", e));
+    
+    async_std::task::spawn({
+        let listen_addr = listen_addr.clone();
+        let dialer_id = dialer_id.clone();
+        async move {
+            let mut listener = listener_transport.listen_on(listen_addr).unwrap();
+            loop {
+                let (upgrade, _remote_addr) = match listener.next().await.unwrap().unwrap().into_upgrade() {
+                    Some(u) => u,
+                    None => continue
+                };
 
-    let dialer = dialer_transport.dial(listen_addr).unwrap()
-        .map(move |(peer, _mplex)| {
-            assert_eq!(peer, listener_id)
-        });
+                let (peer, _mplex) = upgrade.await.unwrap();
+                assert_eq!(peer, dialer_id);
+            }
+        }
+    });
 
-    let mut rt = tokio::runtime::Runtime::new().unwrap();
-    rt.spawn(listener);
-    rt.block_on(dialer).unwrap()
+    async_std::task::block_on(async move {
+        let (peer, _mplex) = dialer_transport.dial(listen_addr).unwrap().await.unwrap();
+        assert_eq!(peer, listener_id);
+    });
 }
 
diff --git a/core/tests/util.rs b/core/tests/util.rs
index 69b1f936..395e0d9c 100644
--- a/core/tests/util.rs
+++ b/core/tests/util.rs
@@ -29,11 +29,11 @@ where
 {
     type Output = Result<M, M::Error>;
 
-    fn poll(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> {
+    fn poll(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> {
         loop {
             match std::mem::replace(&mut self.state, CloseMuxerState::Done) {
                 CloseMuxerState::Close(muxer) => {
-                    if muxer.close()?.is_not_ready() {
+                    if !muxer.close(cx)?.is_ready() {
                         self.state = CloseMuxerState::Close(muxer);
                         return Poll::Pending
                     }
@@ -45,3 +45,5 @@ where
     }
 }
 
+impl<M> Unpin for CloseMuxer<M> {
+}