diff --git a/src/accountant.rs b/src/accountant.rs
index bdad3cf6bf..9d6602e57d 100644
--- a/src/accountant.rs
+++ b/src/accountant.rs
@@ -2,20 +2,20 @@
 //! event log to record transactions. Its users can deposit funds and
 //! transfer funds to other users.
 
-use hash::Hash;
+use chrono::prelude::*;
 use entry::Entry;
 use event::Event;
-use plan::{Plan, Witness};
-use transaction::Transaction;
-use signature::{KeyPair, PublicKey, Signature};
-use mint::Mint;
+use hash::Hash;
 use historian::Historian;
+use mint::Mint;
+use plan::{Plan, Witness};
 use recorder::Signal;
-use std::sync::mpsc::SendError;
-use std::collections::{HashMap, HashSet};
+use signature::{KeyPair, PublicKey, Signature};
 use std::collections::hash_map::Entry::Occupied;
+use std::collections::{HashMap, HashSet};
 use std::result;
-use chrono::prelude::*;
+use std::sync::mpsc::SendError;
+use transaction::Transaction;
 
 #[derive(Debug, PartialEq, Eq)]
 pub enum AccountingError {
@@ -223,8 +223,8 @@ impl Accountant {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use signature::KeyPairUtil;
     use recorder::ExitReason;
+    use signature::KeyPairUtil;
 
     #[test]
     fn test_accountant() {
diff --git a/src/accountant_skel.rs b/src/accountant_skel.rs
index 2f82f6441c..d4c175edbc 100644
--- a/src/accountant_skel.rs
+++ b/src/accountant_skel.rs
@@ -1,24 +1,26 @@
 use accountant::Accountant;
-use transaction::Transaction;
-use signature::PublicKey;
-use hash::Hash;
-use entry::Entry;
-use std::net::UdpSocket;
 use bincode::{deserialize, serialize};
+use entry::Entry;
+use hash::Hash;
 use result::Result;
-use streamer;
-use std::sync::{Arc, Mutex};
-use std::time::Duration;
+use serde_json;
+use signature::PublicKey;
+use std::default::Default;
+use std::io::Write;
+use std::net::UdpSocket;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::mpsc::channel;
+use std::sync::{Arc, Mutex};
 use std::thread::{spawn, JoinHandle};
-use std::default::Default;
-use serde_json;
+use std::time::Duration;
+use streamer;
+use transaction::Transaction;
 
-pub struct AccountantSkel {
+pub struct AccountantSkel<W: Write + Send + 'static> {
     pub acc: Accountant,
     pub last_id: Hash,
     pub ledger: Vec<Entry>,
+    writer: W,
 }
 
 #[cfg_attr(feature = "cargo-clippy", allow(large_enum_variant))]
@@ -37,20 +39,21 @@ pub enum Response {
     Id { id: Hash, is_last: bool },
 }
 
-impl AccountantSkel {
-    pub fn new(acc: Accountant) -> Self {
+impl<W: Write + Send + 'static> AccountantSkel<W> {
+    pub fn new(acc: Accountant, w: W) -> Self {
         let last_id = acc.first_id;
         AccountantSkel {
             acc,
             last_id,
             ledger: vec![],
+            writer: w,
         }
     }
 
-    pub fn sync(self: &mut Self) -> Hash {
+    pub fn sync(&mut self) -> Hash {
         while let Ok(entry) = self.acc.historian.receiver.try_recv() {
             self.last_id = entry.id;
-            println!("{}", serde_json::to_string(&entry).unwrap());
+            write!(self.writer, "{}", serde_json::to_string(&entry).unwrap()).unwrap();
             self.ledger.push(entry);
         }
         self.last_id
@@ -131,7 +134,7 @@ impl AccountantSkel {
 
     /// UDP Server that forwards messages to Accountant methods.
     pub fn serve(
-        obj: Arc<Mutex<AccountantSkel>>,
+        obj: Arc<Mutex<AccountantSkel<W>>>,
         addr: &str,
         exit: Arc<AtomicBool>,
     ) -> Result<Vec<JoinHandle<()>>> {
diff --git a/src/accountant_stub.rs b/src/accountant_stub.rs
index 8bed5a20c5..4336cdd0f4 100644
--- a/src/accountant_stub.rs
+++ b/src/accountant_stub.rs
@@ -2,14 +2,14 @@
 //! event log to record transactions. Its users can deposit funds and
 //! transfer funds to other users.
 
-use std::net::UdpSocket;
-use std::io;
-use bincode::{deserialize, serialize};
-use transaction::Transaction;
-use signature::{KeyPair, PublicKey, Signature};
-use hash::Hash;
-use entry::Entry;
 use accountant_skel::{Request, Response};
+use bincode::{deserialize, serialize};
+use entry::Entry;
+use hash::Hash;
+use signature::{KeyPair, PublicKey, Signature};
+use std::io;
+use std::net::UdpSocket;
+use transaction::Transaction;
 
 pub struct AccountantStub {
     pub addr: String,
@@ -122,12 +122,13 @@ mod tests {
     use super::*;
     use accountant::Accountant;
     use accountant_skel::AccountantSkel;
-    use std::thread::sleep;
-    use std::time::Duration;
     use mint::Mint;
     use signature::{KeyPair, KeyPairUtil};
-    use std::sync::{Arc, Mutex};
+    use std::io::sink;
     use std::sync::atomic::{AtomicBool, Ordering};
+    use std::sync::{Arc, Mutex};
+    use std::thread::sleep;
+    use std::time::Duration;
 
     #[test]
     fn test_accountant_stub() {
@@ -137,9 +138,9 @@ mod tests {
         let acc = Accountant::new(&alice, Some(30));
         let bob_pubkey = KeyPair::new().pubkey();
         let exit = Arc::new(AtomicBool::new(false));
-        let acc = Arc::new(Mutex::new(AccountantSkel::new(acc)));
+        let acc = Arc::new(Mutex::new(AccountantSkel::new(acc, sink())));
         let threads = AccountantSkel::serve(acc, addr, exit.clone()).unwrap();
-        sleep(Duration::from_millis(30));
+        sleep(Duration::from_millis(300));
 
         let socket = UdpSocket::bind(send_addr).unwrap();
         let mut acc = AccountantStub::new(addr, socket);
diff --git a/src/bin/client-demo.rs b/src/bin/client-demo.rs
index eec97db87c..42916f84d6 100644
--- a/src/bin/client-demo.rs
+++ b/src/bin/client-demo.rs
@@ -2,12 +2,12 @@ extern crate serde_json;
 extern crate silk;
 
 use silk::accountant_stub::AccountantStub;
+use silk::mint::Mint;
 use silk::signature::{KeyPair, KeyPairUtil};
 use silk::transaction::Transaction;
-use silk::mint::Mint;
-use std::time::Instant;
-use std::net::UdpSocket;
 use std::io::stdin;
+use std::net::UdpSocket;
+use std::time::Instant;
 
 fn main() {
     let addr = "127.0.0.1:8000";
diff --git a/src/bin/genesis-demo.rs b/src/bin/genesis-demo.rs
index c5fddfead3..2c8f6e9ff1 100644
--- a/src/bin/genesis-demo.rs
+++ b/src/bin/genesis-demo.rs
@@ -1,12 +1,12 @@
 extern crate serde_json;
 extern crate silk;
 
-use silk::mint::Mint;
-use silk::event::Event;
-use silk::transaction::Transaction;
 use silk::entry::create_entry;
-use silk::signature::{KeyPair, KeyPairUtil, PublicKey};
+use silk::event::Event;
 use silk::hash::Hash;
+use silk::mint::Mint;
+use silk::signature::{KeyPair, KeyPairUtil, PublicKey};
+use silk::transaction::Transaction;
 use std::io::stdin;
 
 fn transfer(from: &KeyPair, (to, tokens): (PublicKey, i64), last_id: Hash) -> Event {
diff --git a/src/bin/historian-demo.rs b/src/bin/historian-demo.rs
index 19c3db536b..1652c79431 100644
--- a/src/bin/historian-demo.rs
+++ b/src/bin/historian-demo.rs
@@ -1,16 +1,16 @@
 extern crate silk;
 
-use silk::historian::Historian;
-use silk::hash::Hash;
 use silk::entry::Entry;
+use silk::event::Event;
+use silk::hash::Hash;
+use silk::historian::Historian;
 use silk::ledger::verify_slice;
 use silk::recorder::Signal;
 use silk::signature::{KeyPair, KeyPairUtil};
 use silk::transaction::Transaction;
-use silk::event::Event;
+use std::sync::mpsc::SendError;
 use std::thread::sleep;
 use std::time::Duration;
-use std::sync::mpsc::SendError;
 
 fn create_ledger(hist: &Historian, seed: &Hash) -> Result<(), SendError<Signal>> {
     sleep(Duration::from_millis(15));
diff --git a/src/bin/testnode.rs b/src/bin/testnode.rs
index 43b397d19f..dce8257a29 100644
--- a/src/bin/testnode.rs
+++ b/src/bin/testnode.rs
@@ -1,11 +1,11 @@
 extern crate serde_json;
 extern crate silk;
 
-use silk::accountant_skel::AccountantSkel;
 use silk::accountant::Accountant;
-use std::io::{self, BufRead};
-use std::sync::{Arc, Mutex};
+use silk::accountant_skel::AccountantSkel;
+use std::io::{self, stdout, BufRead};
 use std::sync::atomic::AtomicBool;
+use std::sync::{Arc, Mutex};
 
 fn main() {
     let addr = "127.0.0.1:8000";
@@ -16,7 +16,7 @@ fn main() {
         .map(|line| serde_json::from_str(&line.unwrap()).unwrap());
     let acc = Accountant::new_from_entries(entries, Some(1000));
     let exit = Arc::new(AtomicBool::new(false));
-    let skel = Arc::new(Mutex::new(AccountantSkel::new(acc)));
+    let skel = Arc::new(Mutex::new(AccountantSkel::new(acc, stdout())));
     eprintln!("Listening on {}", addr);
     let threads = AccountantSkel::serve(skel, addr, exit.clone()).unwrap();
     for t in threads {
diff --git a/src/entry.rs b/src/entry.rs
index 56a612bb49..f69d8d125e 100644
--- a/src/entry.rs
+++ b/src/entry.rs
@@ -1,5 +1,5 @@
-use hash::{extend_and_hash, hash, Hash};
 use event::Event;
+use hash::{extend_and_hash, hash, Hash};
 
 #[derive(Serialize, Deserialize, Debug, PartialEq, Eq, Clone)]
 pub struct Entry {
@@ -87,11 +87,11 @@ pub fn next_tick(start_hash: &Hash, num_hashes: u64) -> Entry {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use entry::create_entry;
+    use event::Event;
     use hash::hash;
     use signature::{KeyPair, KeyPairUtil};
     use transaction::Transaction;
-    use event::Event;
-    use entry::create_entry;
 
     #[test]
     fn test_entry_verify() {
diff --git a/src/event.rs b/src/event.rs
index 8afa18b219..a3933bc36a 100644
--- a/src/event.rs
+++ b/src/event.rs
@@ -1,9 +1,9 @@
 //! The `event` crate provides the data structures for log events.
 
+use bincode::serialize;
+use chrono::prelude::*;
 use signature::{KeyPair, KeyPairUtil, PublicKey, Signature, SignatureUtil};
 use transaction::Transaction;
-use chrono::prelude::*;
-use bincode::serialize;
 
 #[derive(Serialize, Deserialize, Debug, PartialEq, Eq, Clone)]
 pub enum Event {
diff --git a/src/historian.rs b/src/historian.rs
index a35f41d835..04a41703ef 100644
--- a/src/historian.rs
+++ b/src/historian.rs
@@ -1,14 +1,14 @@
 //! The `historian` crate provides a microservice for generating a Proof-of-History.
 //! It manages a thread containing a Proof-of-History Logger.
 
-use std::thread::{spawn, JoinHandle};
-use std::collections::HashSet;
-use std::sync::mpsc::{sync_channel, Receiver, SyncSender};
-use std::time::Instant;
-use hash::Hash;
 use entry::Entry;
+use hash::Hash;
 use recorder::{ExitReason, Recorder, Signal};
 use signature::Signature;
+use std::collections::HashSet;
+use std::sync::mpsc::{sync_channel, Receiver, SyncSender};
+use std::thread::{spawn, JoinHandle};
+use std::time::Instant;
 
 pub struct Historian {
     pub sender: SyncSender<Signal>,
diff --git a/src/ledger.rs b/src/ledger.rs
index d858d91799..5beef93e9c 100644
--- a/src/ledger.rs
+++ b/src/ledger.rs
@@ -1,6 +1,7 @@
 //! The `ledger` crate provides the foundational data structures for Proof-of-History,
 //! an ordered log of events in time.
 
+use entry::{next_tick, Entry};
 /// Each entry contains three pieces of data. The `num_hashes` field is the number
 /// of hashes performed since the previous entry.  The `id` field is the result
 /// of hashing `id` from the previous entry `num_hashes` times.  The `event`
@@ -12,9 +13,7 @@
 /// Though processing power varies across nodes, the network gives priority to the
 /// fastest processor. Duration should therefore be estimated by assuming that the hash
 /// was generated by the fastest processor at the time the entry was recorded.
-
 use hash::Hash;
-use entry::{next_tick, Entry};
 use rayon::prelude::*;
 
 /// Verifies the hashes and counts of a slice of events are all consistent.
diff --git a/src/lib.rs b/src/lib.rs
index b3af5bcd7f..3826a1bba6 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,19 +1,19 @@
 #![cfg_attr(feature = "unstable", feature(test))]
-pub mod signature;
-pub mod hash;
-pub mod plan;
-pub mod transaction;
-pub mod event;
-pub mod entry;
-pub mod ledger;
-pub mod mint;
-pub mod recorder;
-pub mod historian;
-pub mod streamer;
 pub mod accountant;
 pub mod accountant_skel;
 pub mod accountant_stub;
+pub mod entry;
+pub mod event;
+pub mod hash;
+pub mod historian;
+pub mod ledger;
+pub mod mint;
+pub mod plan;
+pub mod recorder;
 pub mod result;
+pub mod signature;
+pub mod streamer;
+pub mod transaction;
 extern crate bincode;
 extern crate chrono;
 extern crate generic_array;
diff --git a/src/mint.rs b/src/mint.rs
index 74339cd690..5799d97910 100644
--- a/src/mint.rs
+++ b/src/mint.rs
@@ -1,12 +1,12 @@
 //! A library for generating the chain's genesis block.
 
-use event::Event;
-use transaction::Transaction;
-use signature::{KeyPair, KeyPairUtil, PublicKey};
 use entry::Entry;
 use entry::create_entry;
+use event::Event;
 use hash::{hash, Hash};
 use ring::rand::SystemRandom;
+use signature::{KeyPair, KeyPairUtil, PublicKey};
+use transaction::Transaction;
 use untrusted::Input;
 
 #[derive(Serialize, Deserialize, Debug)]
diff --git a/src/plan.rs b/src/plan.rs
index f28ccec452..3ef51eed80 100644
--- a/src/plan.rs
+++ b/src/plan.rs
@@ -3,8 +3,8 @@
 //! which it uses to reduce the payment plan. When the plan is reduced to a
 //! `Payment`, the payment is executed.
 
-use signature::PublicKey;
 use chrono::prelude::*;
+use signature::PublicKey;
 use std::mem;
 
 pub enum Witness {
diff --git a/src/recorder.rs b/src/recorder.rs
index a590cd8783..14b6a26348 100644
--- a/src/recorder.rs
+++ b/src/recorder.rs
@@ -5,12 +5,12 @@
 //! Event, the latest hash, and the number of hashes since the last event.
 //! The resulting stream of entries represents ordered events in time.
 
-use std::sync::mpsc::{Receiver, SyncSender, TryRecvError};
-use std::time::{Duration, Instant};
-use std::mem;
-use hash::{hash, Hash};
 use entry::{create_entry_mut, Entry};
 use event::Event;
+use hash::{hash, Hash};
+use std::mem;
+use std::sync::mpsc::{Receiver, SyncSender, TryRecvError};
+use std::time::{Duration, Instant};
 
 #[cfg_attr(feature = "cargo-clippy", allow(large_enum_variant))]
 pub enum Signal {
diff --git a/src/result.rs b/src/result.rs
index 96f2f7ff49..ea96453175 100644
--- a/src/result.rs
+++ b/src/result.rs
@@ -1,7 +1,7 @@
+use bincode;
 use serde_json;
 use std;
 use std::any::Any;
-use bincode;
 
 #[derive(Debug)]
 pub enum Error {
@@ -62,16 +62,16 @@ impl std::convert::From<std::boxed::Box<bincode::ErrorKind>> for Error {
 
 #[cfg(test)]
 mod tests {
-    use result::Result;
     use result::Error;
+    use result::Result;
+    use serde_json;
+    use std::io;
+    use std::io::Write;
     use std::net::SocketAddr;
     use std::sync::mpsc::RecvError;
     use std::sync::mpsc::RecvTimeoutError;
-    use std::thread;
-    use std::io;
-    use std::io::Write;
-    use serde_json;
     use std::sync::mpsc::channel;
+    use std::thread;
 
     fn addr_parse_error() -> Result<SocketAddr> {
         let r = "12fdfasfsafsadfs".parse()?;
diff --git a/src/streamer.rs b/src/streamer.rs
index fe0b9ed153..3ad270ad8d 100644
--- a/src/streamer.rs
+++ b/src/streamer.rs
@@ -1,11 +1,11 @@
-use std::sync::{Arc, Mutex, RwLock};
+use result::{Error, Result};
+use std::fmt;
+use std::net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr, UdpSocket};
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::mpsc;
-use std::fmt;
-use std::time::Duration;
-use std::net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr, UdpSocket};
+use std::sync::{Arc, Mutex, RwLock};
 use std::thread::{spawn, JoinHandle};
-use result::{Error, Result};
+use std::time::Duration;
 
 const BLOCK_SIZE: usize = 1024 * 8;
 pub const PACKET_SIZE: usize = 256;
@@ -282,15 +282,15 @@ pub fn responder(
 mod bench {
     extern crate test;
     use self::test::Bencher;
-    use std::thread::sleep;
-    use std::sync::{Arc, Mutex};
+    use result::Result;
     use std::net::{SocketAddr, UdpSocket};
+    use std::sync::atomic::{AtomicBool, Ordering};
+    use std::sync::mpsc::channel;
+    use std::sync::{Arc, Mutex};
+    use std::thread::sleep;
+    use std::thread::{spawn, JoinHandle};
     use std::time::Duration;
     use std::time::SystemTime;
-    use std::thread::{spawn, JoinHandle};
-    use std::sync::mpsc::channel;
-    use std::sync::atomic::{AtomicBool, Ordering};
-    use result::Result;
     use streamer::{allocate, receiver, recycle, Packet, PacketRecycler, Receiver, PACKET_SIZE};
 
     fn producer(
@@ -381,13 +381,13 @@ mod bench {
 
 #[cfg(test)]
 mod test {
-    use std::sync::{Arc, Mutex};
+    use std::io;
+    use std::io::Write;
     use std::net::UdpSocket;
-    use std::time::Duration;
     use std::sync::atomic::{AtomicBool, Ordering};
     use std::sync::mpsc::channel;
-    use std::io::Write;
-    use std::io;
+    use std::sync::{Arc, Mutex};
+    use std::time::Duration;
     use streamer::{allocate, receiver, responder, Packet, Packets, Receiver, Response, Responses,
                    PACKET_SIZE};
 
diff --git a/src/transaction.rs b/src/transaction.rs
index 482bdddf57..7e7674c195 100644
--- a/src/transaction.rs
+++ b/src/transaction.rs
@@ -1,10 +1,10 @@
 //! The `transaction` crate provides functionality for creating log transactions.
 
-use signature::{KeyPair, KeyPairUtil, PublicKey, Signature, SignatureUtil};
 use bincode::serialize;
-use hash::Hash;
 use chrono::prelude::*;
+use hash::Hash;
 use plan::{Condition, Payment, Plan};
+use signature::{KeyPair, KeyPairUtil, PublicKey, Signature, SignatureUtil};
 
 #[derive(Serialize, Deserialize, Debug, PartialEq, Eq, Clone)]
 pub struct Transaction {