diff --git a/artiq/firmware/Cargo.lock b/artiq/firmware/Cargo.lock
index 3370bc073..673c6e9e0 100644
--- a/artiq/firmware/Cargo.lock
+++ b/artiq/firmware/Cargo.lock
@@ -204,6 +204,8 @@ dependencies = [
  "byteorder 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "cslice 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "dyld 0.0.0",
+ "failure 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "failure_derive 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "io 0.0.0",
  "log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
diff --git a/artiq/firmware/ksupport/lib.rs b/artiq/firmware/ksupport/lib.rs
index 4122e75c7..229e616c2 100644
--- a/artiq/firmware/ksupport/lib.rs
+++ b/artiq/firmware/ksupport/lib.rs
@@ -127,7 +127,7 @@ extern fn rpc_send_async(service: u32, tag: CSlice<u8>, data: *const *const ())
             rpc_proto::send_args(&mut writer, service, tag.as_ref(), data)?;
             writer.position()
         };
-        io::proto::ProtoWrite::write_u32(&mut slice, length as u32)
+        io::ProtoWrite::write_u32(&mut slice, length as u32)
     }).unwrap_or_else(|err| {
         assert!(err == io::Error::UnexpectedEof);
 
diff --git a/artiq/firmware/libio/lib.rs b/artiq/firmware/libio/lib.rs
index 48f07394d..486e4ae7b 100644
--- a/artiq/firmware/libio/lib.rs
+++ b/artiq/firmware/libio/lib.rs
@@ -15,9 +15,11 @@ use core::result;
 
 mod cursor;
 #[cfg(feature = "byteorder")]
-pub mod proto;
+mod proto;
 
 pub use cursor::Cursor;
+#[cfg(feature = "byteorder")]
+pub use proto::{ProtoRead, ProtoWrite};
 
 pub type Result<T, E> = result::Result<T, Error<E>>;
 
diff --git a/artiq/firmware/libproto_artiq/Cargo.toml b/artiq/firmware/libproto_artiq/Cargo.toml
index 19b1884dd..92d5e0d0f 100644
--- a/artiq/firmware/libproto_artiq/Cargo.toml
+++ b/artiq/firmware/libproto_artiq/Cargo.toml
@@ -8,6 +8,8 @@ name = "proto_artiq"
 path = "lib.rs"
 
 [dependencies]
+failure = { version = "0.1", default-features = false }
+failure_derive = { version = "0.1", default-features = false }
 byteorder = { version = "1.0", default-features = false }
 cslice = { version = "0.3" }
 log = { version = "0.4", default-features = false, optional = true }
diff --git a/artiq/firmware/libproto_artiq/analyzer_proto.rs b/artiq/firmware/libproto_artiq/analyzer_proto.rs
index 66c54c753..02f81fce2 100644
--- a/artiq/firmware/libproto_artiq/analyzer_proto.rs
+++ b/artiq/firmware/libproto_artiq/analyzer_proto.rs
@@ -1,5 +1,4 @@
-use io::{Write, Result};
-use io::proto::{ProtoWrite};
+use io::{Write, ProtoWrite, Result};
 
 #[derive(Debug)]
 pub struct Header {
diff --git a/artiq/firmware/libproto_artiq/drtioaux_proto.rs b/artiq/firmware/libproto_artiq/drtioaux_proto.rs
index 1899f0787..1bd4eabb7 100644
--- a/artiq/firmware/libproto_artiq/drtioaux_proto.rs
+++ b/artiq/firmware/libproto_artiq/drtioaux_proto.rs
@@ -1,5 +1,4 @@
-use io::{Read, Write, Error, Result};
-use io::proto::{ProtoRead, ProtoWrite};
+use io::{Read, ProtoRead, Write, ProtoWrite, Error, Result};
 
 #[derive(Debug)]
 pub enum Packet {
diff --git a/artiq/firmware/libproto_artiq/mgmt_proto.rs b/artiq/firmware/libproto_artiq/mgmt_proto.rs
index 490be2e5d..d7c2cb8be 100644
--- a/artiq/firmware/libproto_artiq/mgmt_proto.rs
+++ b/artiq/firmware/libproto_artiq/mgmt_proto.rs
@@ -2,8 +2,7 @@ use alloc::Vec;
 #[cfg(feature = "log")]
 use log;
 
-use io::{Read, Write, Error, Result};
-use io::proto::{ProtoRead, ProtoWrite};
+use io::{Read, ProtoRead, Write, ProtoWrite, Error, Result};
 
 #[derive(Debug)]
 pub enum Request {
diff --git a/artiq/firmware/libproto_artiq/moninj_proto.rs b/artiq/firmware/libproto_artiq/moninj_proto.rs
index b440fab14..d40dc40dc 100644
--- a/artiq/firmware/libproto_artiq/moninj_proto.rs
+++ b/artiq/firmware/libproto_artiq/moninj_proto.rs
@@ -1,5 +1,4 @@
-use io::{Read, Write, Error, Result};
-use io::proto::{ProtoRead, ProtoWrite};
+use io::{Read, ProtoRead, Write, ProtoWrite, Error, Result};
 
 #[derive(Debug)]
 pub enum HostMessage {
diff --git a/artiq/firmware/libproto_artiq/rpc_proto.rs b/artiq/firmware/libproto_artiq/rpc_proto.rs
index 226cb47b6..3e0b6594d 100644
--- a/artiq/firmware/libproto_artiq/rpc_proto.rs
+++ b/artiq/firmware/libproto_artiq/rpc_proto.rs
@@ -1,9 +1,7 @@
 use core::str;
 use cslice::{CSlice, CMutSlice};
 
-use io::{Read, Write, Result};
-use io::proto::{ProtoRead, ProtoWrite};
-
+use io::{ProtoRead, Read, Write, ProtoWrite, Result};
 use self::tag::{Tag, TagIterator, split_tag};
 
 unsafe fn recv_value<T>(reader: &mut T, tag: Tag, data: &mut *mut (),
diff --git a/artiq/firmware/libproto_artiq/session_proto.rs b/artiq/firmware/libproto_artiq/session_proto.rs
index 6e4e91cd4..0253c8e8c 100644
--- a/artiq/firmware/libproto_artiq/session_proto.rs
+++ b/artiq/firmware/libproto_artiq/session_proto.rs
@@ -1,7 +1,6 @@
 use alloc::{Vec, String};
 
-use io::{Read, Write, Error, Result};
-use io::proto::{ProtoRead, ProtoWrite};
+use io::{Read, ProtoRead, Write, ProtoWrite, Error, Result};
 
 fn read_sync<T: Read + ?Sized>(reader: &mut T) -> Result<(), T::ReadError> {
     let mut sync = [0; 4];
diff --git a/artiq/firmware/runtime/mgmt.rs b/artiq/firmware/runtime/mgmt.rs
index d1ae97260..574f55df8 100644
--- a/artiq/firmware/runtime/mgmt.rs
+++ b/artiq/firmware/runtime/mgmt.rs
@@ -1,6 +1,6 @@
 use log::{self, LevelFilter};
 
-use io::{self, Read, Write, proto::ProtoWrite};
+use io::{self, Read, Write, ProtoWrite};
 use board_misoc::boot;
 use logger_artiq::BufferLogger;
 use sched::Io;