diff --git a/Cargo.toml b/Cargo.toml
index a5b5c4f0..e748953d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -24,6 +24,7 @@ rustdoc-args = ["--cfg", "feature=\"docs\""]
 [features]
 default = [
   "std",
+  "async-io",
   "async-task",
   "kv-log-macro",
   "log",
@@ -77,6 +78,7 @@ futures-timer = { version = "3.0.2", optional = true }
 surf = { version = "1.0.3", optional = true }
 
 [target.'cfg(not(target_os = "unknown"))'.dependencies]
+async-io = { version = "0.1.5", optional = true }
 smol = { version = "0.1.17", optional = true }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
diff --git a/src/net/tcp/listener.rs b/src/net/tcp/listener.rs
index 09f5812f..8c87fc5f 100644
--- a/src/net/tcp/listener.rs
+++ b/src/net/tcp/listener.rs
@@ -2,7 +2,7 @@ use std::future::Future;
 use std::net::SocketAddr;
 use std::pin::Pin;
 
-use smol::Async;
+use async_io::Async;
 
 use crate::io;
 use crate::net::{TcpStream, ToSocketAddrs};
@@ -81,7 +81,7 @@ impl TcpListener {
         let addrs = addrs.to_socket_addrs().await?;
 
         for addr in addrs {
-            match Async::<std::net::TcpListener>::bind(&addr) {
+            match Async::<std::net::TcpListener>::bind(addr) {
                 Ok(listener) => {
                     return Ok(TcpListener { watcher: listener });
                 }
@@ -227,7 +227,7 @@ cfg_unix! {
 
     impl IntoRawFd for TcpListener {
         fn into_raw_fd(self) -> RawFd {
-            self.watcher.into_raw_fd()
+            self.watcher.into_inner().unwrap().into_raw_fd()
         }
     }
 }
@@ -251,7 +251,7 @@ cfg_windows! {
 
     impl IntoRawSocket for TcpListener {
         fn into_raw_socket(self) -> RawSocket {
-            self.watcher.into_raw_socket()
+            self.watcher.into_inner().unwrap().into_raw_socket()
         }
     }
 }
diff --git a/src/net/tcp/stream.rs b/src/net/tcp/stream.rs
index 63232fa3..f7bd5c91 100644
--- a/src/net/tcp/stream.rs
+++ b/src/net/tcp/stream.rs
@@ -2,7 +2,7 @@ use std::io::{IoSlice, IoSliceMut};
 use std::net::SocketAddr;
 use std::pin::Pin;
 
-use smol::Async;
+use async_io::Async;
 
 use crate::io::{self, Read, Write};
 use crate::net::ToSocketAddrs;
@@ -77,7 +77,7 @@ impl TcpStream {
         let addrs = addrs.to_socket_addrs().await?;
 
         for addr in addrs {
-            match Async::<std::net::TcpStream>::connect(&addr).await {
+            match Async::<std::net::TcpStream>::connect(addr).await {
                 Ok(stream) => {
                     return Ok(TcpStream {
                         watcher: Arc::new(stream),
diff --git a/src/net/udp/mod.rs b/src/net/udp/mod.rs
index d361a6fc..dd47e058 100644
--- a/src/net/udp/mod.rs
+++ b/src/net/udp/mod.rs
@@ -2,7 +2,7 @@ use std::io;
 use std::net::SocketAddr;
 use std::net::{Ipv4Addr, Ipv6Addr};
 
-use smol::Async;
+use async_io::Async;
 
 use crate::net::ToSocketAddrs;
 use crate::utils::Context as _;
@@ -74,7 +74,7 @@ impl UdpSocket {
         let addrs = addrs.to_socket_addrs().await?;
 
         for addr in addrs {
-            match Async::<std::net::UdpSocket>::bind(&addr) {
+            match Async::<std::net::UdpSocket>::bind(addr) {
                 Ok(socket) => {
                     return Ok(UdpSocket { watcher: socket });
                 }
@@ -506,7 +506,7 @@ cfg_unix! {
 
     impl IntoRawFd for UdpSocket {
         fn into_raw_fd(self) -> RawFd {
-            self.watcher.into_raw_fd()
+            self.watcher.into_inner().unwrap().into_raw_fd()
         }
     }
 }
@@ -530,7 +530,7 @@ cfg_windows! {
 
     impl IntoRawSocket for UdpSocket {
         fn into_raw_socket(self) -> RawSocket {
-            self.watcher.into_raw_socket()
+            self.watcher.into_inner().unwrap().into_raw_socket()
         }
     }
 }
diff --git a/src/os/unix/net/datagram.rs b/src/os/unix/net/datagram.rs
index 52c6b07f..83ef9fe9 100644
--- a/src/os/unix/net/datagram.rs
+++ b/src/os/unix/net/datagram.rs
@@ -4,7 +4,7 @@ use std::fmt;
 use std::net::Shutdown;
 use std::os::unix::net::UnixDatagram as StdUnixDatagram;
 
-use smol::Async;
+use async_io::Async;
 
 use super::SocketAddr;
 use crate::io;
@@ -335,6 +335,6 @@ impl FromRawFd for UnixDatagram {
 
 impl IntoRawFd for UnixDatagram {
     fn into_raw_fd(self) -> RawFd {
-        self.watcher.into_raw_fd()
+        self.watcher.into_inner().unwrap().into_raw_fd()
     }
 }
diff --git a/src/os/unix/net/listener.rs b/src/os/unix/net/listener.rs
index a63bd4b6..078b780d 100644
--- a/src/os/unix/net/listener.rs
+++ b/src/os/unix/net/listener.rs
@@ -5,7 +5,7 @@ use std::future::Future;
 use std::os::unix::net::UnixListener as StdUnixListener;
 use std::pin::Pin;
 
-use smol::Async;
+use async_io::Async;
 
 use super::SocketAddr;
 use super::UnixStream;
@@ -217,6 +217,6 @@ impl FromRawFd for UnixListener {
 
 impl IntoRawFd for UnixListener {
     fn into_raw_fd(self) -> RawFd {
-        self.watcher.into_raw_fd()
+        self.watcher.into_inner().unwrap().into_raw_fd()
     }
 }
diff --git a/src/os/unix/net/stream.rs b/src/os/unix/net/stream.rs
index 74bd6aef..3b2fe36f 100644
--- a/src/os/unix/net/stream.rs
+++ b/src/os/unix/net/stream.rs
@@ -5,7 +5,7 @@ use std::net::Shutdown;
 use std::os::unix::net::UnixStream as StdUnixStream;
 use std::pin::Pin;
 
-use smol::Async;
+use async_io::Async;
 
 use super::SocketAddr;
 use crate::io::{self, Read, Write};
diff --git a/src/utils.rs b/src/utils.rs
index db916ed6..f3299f63 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -61,7 +61,7 @@ pub(crate) trait Context {
 
 #[cfg(all(not(target_os = "unknown"), feature = "default"))]
 mod timer {
-    pub type Timer = smol::Timer;
+    pub type Timer = async_io::Timer;
 }
 
 #[cfg(any(feature = "unstable", feature = "default"))]
@@ -69,7 +69,7 @@ pub(crate) fn timer_after(dur: std::time::Duration) -> timer::Timer {
     #[cfg(all(not(target_os = "unknown"), feature = "default"))]
     once_cell::sync::Lazy::force(&crate::rt::RUNTIME);
 
-    Timer::after(dur)
+    Timer::new(dur)
 }
 
 #[cfg(any(
@@ -84,7 +84,7 @@ mod timer {
     pub(crate) struct Timer(futures_timer::Delay);
 
     impl Timer {
-        pub(crate) fn after(dur: std::time::Duration) -> Self {
+        pub(crate) fn new(dur: std::time::Duration) -> Self {
             Timer(futures_timer::Delay::new(dur))
         }
     }