diff --git a/Cargo.toml b/Cargo.toml
index 62d5ee3..f1ca09e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,7 +11,7 @@ repository = "https://github.com/sunfishcode/char-device"
 exclude = ["/.github"]
 
 [dependencies]
-async-std = { version = "1.10.0", optional = true }
+async-std = { version = "1.10.0", optional = true, features = ["io_safety"] }
 tokio = { version = "1.8.1", optional = true, features = ["fs"] }
 io-extras = "0.18.0"
 io-lifetimes = { version = "2.0.0", default-features = false }
@@ -23,7 +23,7 @@ rustix = { version = "1.0.0", features = ["fs"] }
 winx = "0.36.0"
 
 [dev-dependencies]
-async-std = { version = "1.10.0", features = ["attributes"] }
+async-std = { version = "1.13.0", features = ["attributes"] }
 tokio = { version = "1.6.0", features = ["io-util", "macros", "rt"] }
 
 [features]
diff --git a/README.md b/README.md
index 6ad4533..444c164 100644
--- a/README.md
+++ b/README.md
@@ -15,7 +15,4 @@
 This crate defines the [`CharDevice`] struct, a simple wrapper around
 `std::fs::File` for character devices.
 
-Support for async-std and tokio is temporarily disabled until those crates
-contain the needed implementations of the I/O safety traits.
-
 [`CharDevice`]: https://docs.rs/char-device/latest/char_device/struct.CharDevice.html
diff --git a/src/async_std.rs b/src/async_std.rs
index b01bbb1..bd7d9ab 100644
--- a/src/async_std.rs
+++ b/src/async_std.rs
@@ -9,8 +9,8 @@ use {
     ::async_std::os::windows::io::{AsRawHandle, IntoRawHandle, RawHandle},
     io_extras::os::windows::{
         AsHandleOrSocket, AsRawHandleOrSocket, AsRawReadWriteHandleOrSocket,
-        AsReadWriteHandleOrSocket, BorrowedHandleOrSocket,
-        IntoRawHandleOrSocket, OwnedHandleOrSocket, RawHandleOrSocket,
+        AsReadWriteHandleOrSocket, BorrowedHandleOrSocket, IntoRawHandleOrSocket,
+        OwnedHandleOrSocket, RawHandleOrSocket,
     },
     io_lifetimes::{AsFilelike, AsHandle, BorrowedHandle, OwnedHandle},
 };
@@ -57,7 +57,8 @@ impl AsyncStdCharDevice {
 
         #[cfg(windows)]
         {
-            let file_type = winx::winapi_util::file::typ(&*file.as_filelike_view::<std::fs::File>())?;
+            let file_type =
+                winx::winapi_util::file::typ(&*file.as_filelike_view::<std::fs::File>())?;
             if !file_type.is_char() {
                 return Err(io::Error::new(
                     io::ErrorKind::Other,
@@ -257,7 +258,7 @@ impl IntoRawHandleOrSocket for AsyncStdCharDevice {
 }
 
 #[cfg(windows)]
-impl From<AsyncStdCharDevice> for OwnedHandleOrSocket  {
+impl From<AsyncStdCharDevice> for OwnedHandleOrSocket {
     #[inline]
     fn from(char_device: AsyncStdCharDevice) -> Self {
         char_device.0.into()
diff --git a/src/lib.rs b/src/lib.rs
index 33508f2..131e3fd 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -4,22 +4,14 @@
 #![cfg_attr(can_vector, feature(can_vector))]
 #![cfg_attr(write_all_vectored, feature(write_all_vectored))]
 
-/*
 #[cfg(feature = "async-std")]
 mod async_std;
-*/
 mod char_device;
-/*
 #[cfg(feature = "tokio")]
 mod tokio;
-*/
 
-/*
 #[cfg(feature = "async-std")]
 pub use crate::async_std::AsyncStdCharDevice;
-*/
 pub use crate::char_device::CharDevice;
-/*
 #[cfg(feature = "tokio")]
 pub use crate::tokio::TokioCharDevice;
-*/
diff --git a/src/tokio.rs b/src/tokio.rs
index de4ac36..2546f28 100644
--- a/src/tokio.rs
+++ b/src/tokio.rs
@@ -1,4 +1,4 @@
-use io_lifetimes::{FromFilelike, IntoFilelike};
+use io_lifetimes::IntoFilelike;
 use std::io::IoSlice;
 use std::path::Path;
 use std::pin::Pin;
@@ -40,7 +40,8 @@ impl TokioCharDevice {
     pub async fn new<Filelike: IntoFilelike + AsyncRead + AsyncWrite>(
         filelike: Filelike,
     ) -> io::Result<Self> {
-        Self::_new(File::from_into_filelike(filelike)).await
+        let std_file = std::fs::File::from(filelike.into_filelike());
+        Self::_new(File::from_std(std_file)).await
     }
 
     async fn _new(file: File) -> io::Result<Self> {
@@ -57,7 +58,8 @@ impl TokioCharDevice {
 
         #[cfg(windows)]
         {
-            let file_type = winx::winapi_util::file::typ(&*file.as_filelike_view::<std::fs::File>())?;
+            let file_type =
+                winx::winapi_util::file::typ(&*file.as_filelike_view::<std::fs::File>())?;
             if !file_type.is_char() {
                 return Err(io::Error::new(
                     io::ErrorKind::Other,
@@ -84,7 +86,8 @@ impl TokioCharDevice {
     /// Doesn't check that the handle is valid or a character device.
     #[inline]
     pub unsafe fn new_unchecked<Filelike: IntoFilelike>(filelike: Filelike) -> Self {
-        Self(File::from_into_filelike(filelike))
+        let std_file = std::fs::File::from(filelike.into_filelike());
+        Self(File::from_std(std_file))
     }
 
     /// Construct a new `CharDevice` which discards writes and reads nothing.
diff --git a/tests/null.rs b/tests/null.rs
index cf51aac..112f9e8 100644
--- a/tests/null.rs
+++ b/tests/null.rs
@@ -1,12 +1,8 @@
-/*
 #[cfg(feature = "async-std")]
 use char_device::AsyncStdCharDevice;
-*/
 use char_device::CharDevice;
-/*
 #[cfg(feature = "tokio")]
 use char_device::TokioCharDevice;
-*/
 
 #[test]
 fn null() {
@@ -19,7 +15,6 @@ fn null() {
     assert_eq!(char_device.read(&mut buf).unwrap(), 0);
 }
 
-/*
 #[cfg(feature = "async-std")]
 #[async_std::test]
 async fn async_std_null() {
@@ -43,4 +38,3 @@ async fn tokio_null() {
     let mut buf = vec![0_u8; 32];
     assert_eq!(char_device.read(&mut buf).await.unwrap(), 0);
 }
-*/
diff --git a/tests/tty.rs b/tests/tty.rs
index ee6ec45..f9e7595 100644
--- a/tests/tty.rs
+++ b/tests/tty.rs
@@ -1,14 +1,10 @@
 #![cfg(unix)]
 
-/*
 #[cfg(feature = "async-std")]
 use char_device::AsyncStdCharDevice;
-*/
 use char_device::CharDevice;
-/*
 #[cfg(feature = "tokio")]
 use char_device::TokioCharDevice;
-*/
 
 #[test]
 fn tty() {
@@ -25,7 +21,6 @@ fn tty() {
     };
 }
 
-/*
 #[cfg(feature = "async-std")]
 #[async_std::test]
 async fn async_std_tty() {
@@ -57,4 +52,3 @@ async fn tokio_tty() {
         },
     };
 }
-*/