diff --git a/src/Cargo.lock b/src/Cargo.lock
index 1cd121c..645216a 100644
--- a/src/Cargo.lock
+++ b/src/Cargo.lock
@@ -229,7 +229,6 @@ name = "io"
 version = "0.0.0"
 dependencies = [
  "byteorder",
- "core_io",
  "libsupport_zynq",
 ]
 
@@ -239,7 +238,6 @@ version = "0.1.0"
 dependencies = [
  "build_zynq",
  "byteorder",
- "core_io",
  "cslice",
  "dwarf",
  "dyld",
@@ -278,7 +276,6 @@ name = "libboard_artiq"
 version = "0.0.0"
 dependencies = [
  "build_zynq",
- "core_io",
  "crc",
  "embedded-hal",
  "io",
@@ -519,7 +516,6 @@ dependencies = [
  "async-recursion",
  "build_zynq",
  "byteorder",
- "core_io",
  "cslice",
  "dwarf",
  "dyld",
@@ -560,7 +556,6 @@ version = "0.0.0"
 dependencies = [
  "build_zynq",
  "byteorder",
- "core_io",
  "crc",
  "cslice",
  "embedded-hal",
diff --git a/src/libboard_artiq/Cargo.toml.tpl b/src/libboard_artiq/Cargo.toml.tpl
index ab8270f..7e3b963 100644
--- a/src/libboard_artiq/Cargo.toml.tpl
+++ b/src/libboard_artiq/Cargo.toml.tpl
@@ -20,7 +20,6 @@ build_zynq = { path = "../libbuild_zynq" }
 log = "0.4"
 log_buffer = { version = "1.2" }
 crc = { version = "1.7", default-features = false }
-core_io = { version = "0.1", features = ["collections"] }
 embedded-hal = "0.2"
 nb = "1.0"
 void = { version = "1", default-features = false }
diff --git a/src/libboard_artiq/src/drtioaux.rs b/src/libboard_artiq/src/drtioaux.rs
index 9e27ac9..4bb12cc 100644
--- a/src/libboard_artiq/src/drtioaux.rs
+++ b/src/libboard_artiq/src/drtioaux.rs
@@ -1,9 +1,8 @@
 use core::slice;
 
-use core_io::{Error as IoError, ErrorKind as IoErrorKind};
 use crc;
 use io::{proto::{ProtoRead, ProtoWrite},
-         Cursor};
+         Cursor, Error as IoError};
 use libboard_zynq::{time::Milliseconds, timer::GlobalTimer};
 
 pub use crate::drtioaux_proto::Packet;
@@ -80,7 +79,7 @@ pub fn recv(linkno: u8) -> Result<Option<Packet>, Error> {
 
     receive(linkno, |buffer| {
         if buffer.len() < 8 {
-            return Err(IoError::new(IoErrorKind::UnexpectedEof, "Unexpected end").into());
+            return Err(IoError::UnexpectedEnd).into());
         }
 
         let mut reader = Cursor::new(buffer);
diff --git a/src/libboard_artiq/src/drtioaux_async.rs b/src/libboard_artiq/src/drtioaux_async.rs
index 08f18cf..3244432 100644
--- a/src/libboard_artiq/src/drtioaux_async.rs
+++ b/src/libboard_artiq/src/drtioaux_async.rs
@@ -1,9 +1,8 @@
 use core::slice;
 
-use core_io::{Error as IoError, ErrorKind as IoErrorKind};
 use crc;
 use io::{proto::{ProtoRead, ProtoWrite},
-         Cursor};
+         Cursor, Error as IoError};
 use libasync::{block_async, task};
 use libboard_zynq::{time::Milliseconds, timer::GlobalTimer};
 use nb;
@@ -58,7 +57,7 @@ pub async fn recv(linkno: u8) -> Result<Option<Packet>, Error> {
 
     receive(linkno, |buffer| {
         if buffer.len() < 8 {
-            return Err(IoError::new(IoErrorKind::UnexpectedEof, "Unexpected end").into());
+            return Err(IoError::UnexpectedEnd).into());
         }
 
         let mut reader = Cursor::new(buffer);
diff --git a/src/libboard_artiq/src/drtioaux_proto.rs b/src/libboard_artiq/src/drtioaux_proto.rs
index d00cf96..370d288 100644
--- a/src/libboard_artiq/src/drtioaux_proto.rs
+++ b/src/libboard_artiq/src/drtioaux_proto.rs
@@ -1,4 +1,4 @@
-use core_io::{Error as IoError, Read, Write};
+use io::{Error as IoError, Read, Write};
 use io::proto::{ProtoRead, ProtoWrite};
 
 const MAX_PACKET: usize = 1024;
@@ -10,13 +10,13 @@ pub const SAT_PAYLOAD_MAX_SIZE: usize  = /*max size*/MAX_PACKET - /*CRC*/4 - /*p
 pub const MASTER_PAYLOAD_MAX_SIZE: usize = SAT_PAYLOAD_MAX_SIZE - /*source*/1 - /*destination*/1 - /*ID*/4;
 
 #[derive(Debug)]
-pub enum Error {
+pub enum Error<T> {
     UnknownPacket(u8),
-    Io(IoError),
+    Io(IoError<T>),
 }
 
-impl From<IoError> for Error {
-    fn from(value: IoError) -> Error {
+impl<T> From<IoError<T>> for Error<T> {
+    fn from(value: IoError<T>) -> Error<T> {
         Error::Io(value)
     }
 }
@@ -362,7 +362,7 @@ pub enum Packet {
 }
 
 impl Packet {
-    pub fn read_from<R>(reader: &mut R) -> Result<Self, Error>
+    pub fn read_from<R>(reader: &mut R) -> Result<Self, Error<R::ReadError>>
     where R: Read + ?Sized {
         Ok(match reader.read_u8()? {
             0x00 => Packet::EchoRequest,
@@ -749,7 +749,7 @@ impl Packet {
         })
     }
 
-    pub fn write_to<W>(&self, writer: &mut W) -> Result<(), IoError>
+    pub fn write_to<W>(&self, writer: &mut W) -> Result<(), IoError<W::WriteError>>
     where W: Write + ?Sized {
         match *self {
             Packet::EchoRequest => writer.write_u8(0x00)?,
diff --git a/src/libboard_artiq/src/lib.rs b/src/libboard_artiq/src/lib.rs
index 70c4cb6..b70ec4d 100644
--- a/src/libboard_artiq/src/lib.rs
+++ b/src/libboard_artiq/src/lib.rs
@@ -3,7 +3,6 @@
 #![feature(naked_functions)]
 #![feature(asm)]
 
-extern crate core_io;
 extern crate crc;
 extern crate embedded_hal;
 extern crate io;
diff --git a/src/libio/Cargo.toml.tpl b/src/libio/Cargo.toml.tpl
index f6bd041..e5a08d3 100644
--- a/src/libio/Cargo.toml.tpl
+++ b/src/libio/Cargo.toml.tpl
@@ -8,7 +8,6 @@ name = "io"
 path = "lib.rs"
 
 [dependencies]
-core_io = { version = "0.1", features = ["collections"] }
 byteorder = { version = "1.0", default-features = false, optional = true }
 
 libsupport_zynq = { path = "@@ZYNQ_RS@@/libsupport_zynq", default-features = false, features = ["alloc_core"] }
diff --git a/src/libio/cursor.rs b/src/libio/cursor.rs
index bd397ac..b07ed4d 100644
--- a/src/libio/cursor.rs
+++ b/src/libio/cursor.rs
@@ -1,7 +1,7 @@
 #[cfg(feature = "alloc")]
 use alloc::vec::Vec;
 
-use core_io::{Error as IoError, Read, Write};
+use crate::{Read, Write};
 
 #[derive(Debug, Clone)]
 pub struct Cursor<T> {
@@ -42,7 +42,9 @@ impl<T> Cursor<T> {
 }
 
 impl<T: AsRef<[u8]>> Read for Cursor<T> {
-    fn read(&mut self, buf: &mut [u8]) -> Result<usize, IoError> {
+    type ReadError = !;
+
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize, Self::ReadError> {
         let data = &self.inner.as_ref()[self.pos..];
         let len = buf.len().min(data.len());
         // ``copy_from_slice`` generates AXI bursts, use a regular loop instead
@@ -55,7 +57,10 @@ impl<T: AsRef<[u8]>> Read for Cursor<T> {
 }
 
 impl Write for Cursor<&mut [u8]> {
-    fn write(&mut self, buf: &[u8]) -> Result<usize, IoError> {
+    type WriteError = !;
+    type FlushError = !;
+
+    fn write(&mut self, buf: &[u8]) -> Result<usize, Self::WriteError> {
         let data = &mut self.inner[self.pos..];
         let len = buf.len().min(data.len());
         for i in 0..len {
@@ -66,20 +71,23 @@ impl Write for Cursor<&mut [u8]> {
     }
 
     #[inline]
-    fn flush(&mut self) -> Result<(), IoError> {
+    fn flush(&mut self) -> Result<(), Self::FlushError> {
         Ok(())
     }
 }
 
 #[cfg(feature = "alloc")]
 impl Write for Cursor<Vec<u8>> {
-    fn write(&mut self, buf: &[u8]) -> Result<usize, IoError> {
+    type WriteError = !;
+    type FlushError = !;
+
+    fn write(&mut self, buf: &[u8]) -> Result<usize, Self::WriteError> {
         self.inner.extend_from_slice(buf);
         Ok(buf.len())
     }
 
     #[inline]
-    fn flush(&mut self) -> Result<(), IoError> {
+    fn flush(&mut self) -> Result<(), Self::FlushError> {
         Ok(())
     }
 }
diff --git a/src/libio/lib.rs b/src/libio/lib.rs
index 7abe5c1..ed115ac 100644
--- a/src/libio/lib.rs
+++ b/src/libio/lib.rs
@@ -3,7 +3,6 @@
 
 #[cfg(feature = "alloc")]
 extern crate alloc;
-extern crate core_io;
 
 #[cfg(feature = "byteorder")]
 extern crate byteorder;
@@ -12,8 +11,142 @@ pub mod cursor;
 #[cfg(feature = "byteorder")]
 pub mod proto;
 
+use core::fmt::{Display, Formatter};
+
 pub use cursor::Cursor;
 #[cfg(all(feature = "byteorder", feature = "alloc"))]
 pub use proto::ReadStringError;
 #[cfg(feature = "byteorder")]
 pub use proto::{ProtoRead, ProtoWrite};
+
+#[derive(Debug, Clone, PartialEq)]
+pub enum Error<T> {
+    UnexpectedEnd,
+    Other(T),
+}
+
+impl<T> From<T> for Error<T> {
+    fn from(value: T) -> Error<T> {
+        Error::Other(value)
+    }
+}
+
+impl<T: Display> Display for Error<T> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), core::fmt::Error> {
+        match self {
+            Error::UnexpectedEnd => write!(f, "unexpected end of stream"),
+            Error::Other(other) => write!(f, "other IO error: {}", other),
+        }
+    }
+}
+
+pub trait Read {
+    type ReadError;
+
+    /// Pull some bytes from this source into the specified buffer, returning
+    /// how many bytes were read.
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize, Self::ReadError>;
+
+    /// Read the exact number of bytes required to fill `buf`.
+    fn read_exact(&mut self, mut buf: &mut [u8]) -> Result<(), Error<Self::ReadError>> {
+        while !buf.is_empty() {
+            let read_bytes = self.read(buf)?;
+            if read_bytes == 0 {
+                return Err(Error::UnexpectedEnd);
+            }
+
+            buf = &mut { buf }[read_bytes..];
+        }
+
+        Ok(())
+    }
+}
+
+impl<'a, T: Read> Read for &'a mut T {
+    type ReadError = T::ReadError;
+
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize, Self::ReadError> {
+        T::read(self, buf)
+    }
+}
+
+pub trait Write {
+    type WriteError;
+    type FlushError;
+
+    /// Write a buffer into this object, returning how many bytes were written.
+    fn write(&mut self, buf: &[u8]) -> Result<usize, Self::WriteError>;
+
+    /// Flush this output stream, ensuring that all intermediately buffered contents
+    /// reach their destination.
+    fn flush(&mut self) -> Result<(), Self::FlushError>;
+
+    /// Attempts to write an entire buffer into `self`.
+    fn write_all(&mut self, mut buf: &[u8]) -> Result<(), Error<Self::WriteError>> {
+        while buf.len() > 0 {
+            let written_bytes = self.write(buf)?;
+            if written_bytes == 0 {
+                return Err(Error::UnexpectedEnd);
+            }
+
+            buf = &buf[written_bytes..];
+        }
+
+        Ok(())
+    }
+
+    /// Hints the writer how much bytes will be written after call to this function.
+    ///
+    /// At least `min` bytes should be written after the call to this function and
+    /// if `max` is `Some(x)` than at most `x` bytes should be written.
+    fn size_hint(&mut self, _min: usize, _max: Option<usize>) {}
+}
+
+impl<'a, T: Write> Write for &'a mut T {
+    type WriteError = T::WriteError;
+    type FlushError = T::FlushError;
+
+    fn write(&mut self, buf: &[u8]) -> Result<usize, Self::WriteError> {
+        T::write(self, buf)
+    }
+
+    fn flush(&mut self) -> Result<(), Self::FlushError> {
+        T::flush(self)
+    }
+
+    fn size_hint(&mut self, min: usize, max: Option<usize>) {
+        T::size_hint(self, min, max)
+    }
+}
+
+impl<'a> Write for &'a mut [u8] {
+    type WriteError = !;
+    type FlushError = !;
+
+    fn write(&mut self, buf: &[u8]) -> Result<usize, Self::WriteError> {
+        let len = buf.len().min(self.len());
+        self[..len].copy_from_slice(&buf[..len]);
+        Ok(len)
+    }
+
+    #[inline]
+    fn flush(&mut self) -> Result<(), Self::FlushError> {
+        Ok(())
+    }
+}
+
+#[cfg(feature = "alloc")]
+impl<'a> Write for alloc::vec::Vec<u8> {
+    type WriteError = !;
+    type FlushError = !;
+
+    fn write(&mut self, buf: &[u8]) -> Result<usize, Self::WriteError> {
+        self.extend_from_slice(buf);
+        Ok(buf.len())
+    }
+
+    #[inline]
+    fn flush(&mut self) -> Result<(), Self::FlushError> {
+        Ok(())
+    }
+}
diff --git a/src/libio/proto.rs b/src/libio/proto.rs
index a7c36b6..c4ba6dc 100644
--- a/src/libio/proto.rs
+++ b/src/libio/proto.rs
@@ -3,7 +3,9 @@ use alloc::{string::String, vec};
 use core::str::Utf8Error;
 
 use byteorder::{ByteOrder, NativeEndian};
-use core_io::{Error as IoError, Read, Write};
+use Error as IoError;
+use Read;
+use Write;
 
 #[allow(dead_code)]
 #[derive(Debug, Clone, PartialEq)]
@@ -147,7 +149,7 @@ pub trait ProtoWrite {
 impl<T> ProtoRead for T
 where T: Read + ?Sized
 {
-    type ReadError = IoError;
+    type ReadError = IoError<T::ReadError>;
 
     fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Self::ReadError> {
         T::read_exact(self, buf)
@@ -157,7 +159,7 @@ where T: Read + ?Sized
 impl<T> ProtoWrite for T
 where T: Write + ?Sized
 {
-    type WriteError = IoError;
+    type WriteError = IoError<T::WriteError>;
 
     fn write_all(&mut self, buf: &[u8]) -> Result<(), Self::WriteError> {
         T::write_all(self, buf)
diff --git a/src/libksupport/Cargo.toml.tpl b/src/libksupport/Cargo.toml.tpl
index 65f9e94..e06c1c9 100644
--- a/src/libksupport/Cargo.toml.tpl
+++ b/src/libksupport/Cargo.toml.tpl
@@ -12,7 +12,6 @@ build_zynq = { path = "../libbuild_zynq" }
 cslice = "0.3"
 log = "0.4"
 nb = "0.1"
-core_io = { version = "0.1", features = ["collections"] }
 byteorder = { version = "1.3", default-features = false }
 void = { version = "1", default-features = false }
 log_buffer = { version = "1.2" }
diff --git a/src/libksupport/src/eh_artiq.rs b/src/libksupport/src/eh_artiq.rs
index 70b27a3..4741c5e 100644
--- a/src/libksupport/src/eh_artiq.rs
+++ b/src/libksupport/src/eh_artiq.rs
@@ -14,10 +14,9 @@
 
 use core::mem;
 
-use core_io::Error as ReadError;
 use cslice::{AsCSlice, CSlice};
 use dwarf::eh::{self, EHAction, EHContext};
-use io::{Cursor, ProtoRead};
+use io::{Cursor, Error as ReadError, ProtoRead, Read};
 use libc::{c_int, c_void, uintptr_t};
 use log::{error, trace};
 use unwind as uw;
@@ -295,7 +294,9 @@ pub unsafe extern "C" fn raise(exception: *const Exception) -> ! {
     unreachable!();
 }
 
-fn read_exception_string<'a>(reader: &mut Cursor<&[u8]>) -> Result<CSlice<'a, u8>, ReadError> {
+fn read_exception_string<'a, 'b>(
+    reader: &mut Cursor<&'b [u8]>,
+) -> Result<CSlice<'a, u8>, ReadError<<Cursor<&'b [u8]> as Read>::ReadError>> {
     let len = reader.read_u32()? as usize;
     if len == usize::MAX {
         let data = reader.read_u32()?;
@@ -311,7 +312,7 @@ fn read_exception_string<'a>(reader: &mut Cursor<&[u8]>) -> Result<CSlice<'a, u8
     }
 }
 
-fn read_exception(raw_exception: &[u8]) -> Result<Exception, ReadError> {
+fn read_exception(raw_exception: &[u8]) -> Result<Exception, ReadError<<Cursor<&[u8]> as Read>::ReadError>> {
     let mut reader = Cursor::new(raw_exception);
 
     let mut byte = reader.read_u8()?;
diff --git a/src/libksupport/src/rpc.rs b/src/libksupport/src/rpc.rs
index 20e10cf..4bfa425 100644
--- a/src/libksupport/src/rpc.rs
+++ b/src/libksupport/src/rpc.rs
@@ -1,9 +1,8 @@
 use core::str;
 
 use byteorder::{ByteOrder, NativeEndian};
-use core_io::{Error, Read, Write};
 use cslice::{CMutSlice, CSlice};
-use io::{ProtoRead, ProtoWrite};
+use io::{Error, ProtoRead, ProtoWrite, Read, Write};
 use log::trace;
 
 use self::tag::{split_tag, Tag, TagIterator};
@@ -37,16 +36,17 @@ pub unsafe fn align_ptr_mut<T>(ptr: *mut ()) -> *mut T {
 
 // versions for reader rather than TcpStream
 // they will be made into sync for satellite subkernels later
-unsafe fn recv_elements<F, R>(
+unsafe fn recv_elements<F, R, E>(
     reader: &mut R,
     elt_tag: Tag,
     length: usize,
     storage: *mut (),
     alloc: &mut F,
-) -> Result<(), Error>
+) -> Result<(), E>
 where
     F: FnMut(usize) -> *mut (),
     R: Read + ?Sized,
+    E: From<Error<R::ReadError>>,
 {
     match elt_tag {
         Tag::Bool => {
@@ -79,10 +79,11 @@ where
     Ok(())
 }
 
-unsafe fn recv_value<F, R>(reader: &mut R, tag: Tag, data: &mut *mut (), alloc: &mut F) -> Result<(), Error>
+unsafe fn recv_value<F, R, E>(reader: &mut R, tag: Tag, data: &mut *mut (), alloc: &mut F) -> Result<(), E>
 where
     F: FnMut(usize) -> *mut (),
     R: Read + ?Sized,
+    E: From<Error<R::ReadError>>,
 {
     macro_rules! consume_value {
         ($ty:ty, | $ptr:ident | $map:expr) => {{
@@ -175,15 +176,16 @@ where
     }
 }
 
-pub fn recv_return<'a, F, R>(
+pub fn recv_return<'a, F, R, E>(
     reader: &mut R,
     tag_bytes: &'a [u8],
     data: *mut (),
     alloc: &mut F,
-) -> Result<&'a [u8], Error>
+) -> Result<&'a [u8], E>
 where
     F: FnMut(usize) -> *mut (),
     R: Read + ?Sized,
+    E: From<Error<R::ReadError>>,
 {
     let mut it = TagIterator::new(tag_bytes);
     trace!("recv ...->{}", it);
@@ -201,7 +203,7 @@ unsafe fn send_elements<W>(
     length: usize,
     data: *const (),
     write_tags: bool,
-) -> Result<(), Error>
+) -> Result<(), Error<W::WriteError>>
 where
     W: Write + ?Sized,
 {
@@ -233,8 +235,15 @@ where
     Ok(())
 }
 
-unsafe fn send_value<W>(writer: &mut W, tag: Tag, data: &mut *const (), write_tags: bool) -> Result<(), Error>
-where W: Write + ?Sized {
+unsafe fn send_value<W>(
+    writer: &mut W,
+    tag: Tag,
+    data: &mut *const (),
+    write_tags: bool,
+) -> Result<(), Error<W::WriteError>>
+where
+    W: Write + ?Sized,
+{
     macro_rules! consume_value {
         ($ty:ty, | $ptr:ident | $map:expr) => {{
             let $ptr = align_ptr::<$ty>(*data);
@@ -337,7 +346,7 @@ pub fn send_args<W>(
     tag_bytes: &[u8],
     data: *const *const (),
     write_tags: bool,
-) -> Result<(), Error>
+) -> Result<(), Error<W::WriteError>>
 where
     W: Write + ?Sized,
 {
diff --git a/src/runtime/Cargo.toml.tpl b/src/runtime/Cargo.toml.tpl
index e57e63e..240485c 100644
--- a/src/runtime/Cargo.toml.tpl
+++ b/src/runtime/Cargo.toml.tpl
@@ -20,7 +20,6 @@ num-derive = "0.3"
 cslice = "0.3"
 log = "0.4"
 embedded-hal = "0.2"
-core_io = { version = "0.1", features = ["collections"] }
 crc = { version = "1.7", default-features = false }
 byteorder = { version = "1.3", default-features = false }
 void = { version = "1", default-features = false }
@@ -46,4 +45,4 @@ libboard_artiq = { path = "../libboard_artiq" }
 
 [dependencies.tar-no-std]
 git = "https://git.m-labs.hk/M-Labs/tar-no-std"
-rev = "2ab6dc5"
\ No newline at end of file
+rev = "2ab6dc5"
diff --git a/src/runtime/src/comms.rs b/src/runtime/src/comms.rs
index 1f6c773..7b0070e 100644
--- a/src/runtime/src/comms.rs
+++ b/src/runtime/src/comms.rs
@@ -1,12 +1,12 @@
 use alloc::{collections::BTreeMap, rc::Rc, string::String, vec, vec::Vec};
 use core::{cell::RefCell, fmt, slice, str};
 
-use core_io::Error as IoError;
 use cslice::CSlice;
 use dyld::elf;
 use futures::{future::FutureExt, select_biased};
 #[cfg(has_drtio)]
 use io::Cursor;
+use io::Error as IoError;
 #[cfg(has_drtio)]
 use ksupport::rpc;
 use ksupport::{kernel, resolve_channel_name};
@@ -78,8 +78,8 @@ impl From<smoltcp::Error> for Error {
     }
 }
 
-impl From<IoError> for Error {
-    fn from(_error: IoError) -> Self {
+impl<T> From<IoError<T>> for Error {
+    fn from(_error: IoError<T>) -> Self {
         Error::IoError
     }
 }
diff --git a/src/satman/Cargo.toml.tpl b/src/satman/Cargo.toml.tpl
index 38f64e6..654f5a9 100644
--- a/src/satman/Cargo.toml.tpl
+++ b/src/satman/Cargo.toml.tpl
@@ -16,7 +16,6 @@ build_zynq = { path = "../libbuild_zynq" }
 [dependencies]
 log = { version = "0.4", default-features = false }
 byteorder = { version = "1.3", default-features = false }
-core_io = { version = "0.1", features = ["collections"] }
 crc = { version = "1.7", default-features = false }
 cslice = "0.3"
 embedded-hal = "0.2"
diff --git a/src/satman/src/main.rs b/src/satman/src/main.rs
index afff3fd..abf6fe7 100644
--- a/src/satman/src/main.rs
+++ b/src/satman/src/main.rs
@@ -5,7 +5,6 @@
 #[macro_use]
 extern crate log;
 extern crate byteorder;
-extern crate core_io;
 extern crate crc;
 extern crate cslice;
 extern crate embedded_hal;
diff --git a/src/satman/src/subkernel.rs b/src/satman/src/subkernel.rs
index a49e29a..93490eb 100644
--- a/src/satman/src/subkernel.rs
+++ b/src/satman/src/subkernel.rs
@@ -4,11 +4,10 @@ use alloc::{collections::BTreeMap,
             vec::Vec};
 use core::{option::NoneError, slice, str};
 
-use core_io::{Error as IoError, Write};
 use cslice::AsCSlice;
 use dma::{Error as DmaError, Manager as DmaManager};
-use io::{Cursor, ProtoWrite};
-use ksupport::{eh_artiq, kernel, rpc, rtio};
+use io::{Cursor, Error as IoError, ProtoWrite, Write};
+use ksupport::{eh_artiq, kernel, rpc};
 use libboard_artiq::{drtio_routing::RoutingTable,
                      drtioaux,
                      drtioaux_proto::{PayloadStatus, MASTER_PAYLOAD_MAX_SIZE},