diff --git a/Cargo.toml b/Cargo.toml
index b5ffe4e41..a0f11033b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -21,6 +21,3 @@ slab = "0.2.0"
 
 [dev-dependencies]
 env_logger = "0.3"
-
-[lib]
-test = false
diff --git a/src/lib.rs b/src/lib.rs
index 0967c6ad6..1aac03654 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -24,7 +24,7 @@ mod event_loop;
 mod tcp;
 mod udp;
 mod timeout;
-pub mod timer_wheel;
+mod timer_wheel;
 #[path = "../../src/slot.rs"]
 mod slot;
 #[path = "../../src/lock.rs"]
diff --git a/src/timer_wheel.rs b/src/timer_wheel.rs
index 6f909460d..eb9f15b98 100644
--- a/src/timer_wheel.rs
+++ b/src/timer_wheel.rs
@@ -291,3 +291,143 @@ impl<T> TimerWheel<T> {
         (ticks as usize) & MASK
     }
 }
+
+#[cfg(test)]
+mod tests {
+    extern crate env_logger;
+
+    use std::time::{Instant, Duration};
+
+    use super::TimerWheel;
+
+    fn ms(amt: u64) -> Duration {
+        Duration::from_millis(amt)
+    }
+
+    #[test]
+    fn smoke() {
+        drop(env_logger::init());
+        let mut timer = TimerWheel::<i32>::new();
+        let now = Instant::now();
+
+        assert!(timer.poll(now).is_none());
+        assert!(timer.poll(now).is_none());
+
+        timer.insert(now + ms(200), 3);
+
+        assert!(timer.poll(now).is_none());
+        assert!(timer.poll(now + ms(100)).is_none());
+        let res = timer.poll(now + ms(200));
+        assert!(res.is_some());
+        assert_eq!(res.unwrap(), 3);
+    }
+
+    #[test]
+    fn poll_past_done() {
+        drop(env_logger::init());
+        let mut timer = TimerWheel::<i32>::new();
+        let now = Instant::now();
+
+        timer.insert(now + ms(200), 3);
+        let res = timer.poll(now + ms(300));
+        assert!(res.is_some());
+        assert_eq!(res.unwrap(), 3);
+    }
+
+    #[test]
+    fn multiple_ready() {
+        drop(env_logger::init());
+        let mut timer = TimerWheel::<i32>::new();
+        let now = Instant::now();
+
+        timer.insert(now + ms(200), 3);
+        timer.insert(now + ms(201), 4);
+        timer.insert(now + ms(202), 5);
+        timer.insert(now + ms(300), 6);
+        timer.insert(now + ms(301), 7);
+
+        let mut found = Vec::new();
+        while let Some(i) = timer.poll(now + ms(400)) {
+            found.push(i);
+        }
+        found.sort();
+        assert_eq!(found, [3, 4, 5, 6, 7]);
+    }
+
+    #[test]
+    fn poll_now() {
+        drop(env_logger::init());
+        let mut timer = TimerWheel::<i32>::new();
+        let now = Instant::now();
+
+        timer.insert(now, 3);
+        let res = timer.poll(now + ms(100));
+        assert!(res.is_some());
+        assert_eq!(res.unwrap(), 3);
+    }
+
+    #[test]
+    fn cancel() {
+        drop(env_logger::init());
+        let mut timer = TimerWheel::<i32>::new();
+        let now = Instant::now();
+
+        let timeout = timer.insert(now + ms(800), 3);
+        assert!(timer.poll(now + ms(200)).is_none());
+        assert!(timer.poll(now + ms(400)).is_none());
+        assert_eq!(timer.cancel(&timeout), Some(3));
+        assert!(timer.poll(now + ms(600)).is_none());
+        assert!(timer.poll(now + ms(800)).is_none());
+        assert!(timer.poll(now + ms(1000)).is_none());
+    }
+
+    #[test]
+    fn next_timeout() {
+        drop(env_logger::init());
+        let mut timer = TimerWheel::<i32>::new();
+        let now = Instant::now();
+
+        assert!(timer.next_timeout().is_none());
+        timer.insert(now + ms(400), 3);
+        let timeout = timer.next_timeout().expect("wanted a next_timeout");
+        assert_eq!(timeout, now + ms(400));
+
+        timer.insert(now + ms(1000), 3);
+        let timeout = timer.next_timeout().expect("wanted a next_timeout");
+        assert_eq!(timeout, now + ms(400));
+    }
+
+    #[test]
+    fn around_the_boundary() {
+        drop(env_logger::init());
+        let mut timer = TimerWheel::<i32>::new();
+        let now = Instant::now();
+
+        timer.insert(now + ms(199), 3);
+        timer.insert(now + ms(200), 4);
+        timer.insert(now + ms(201), 5);
+        timer.insert(now + ms(251), 6);
+
+        let mut found = Vec::new();
+        while let Some(i) = timer.poll(now + ms(200)) {
+            found.push(i);
+        }
+        found.sort();
+        assert_eq!(found, [3, 4, 5]);
+
+        assert_eq!(timer.poll(now + ms(300)), Some(6));
+        assert_eq!(timer.poll(now + ms(300)), None);
+    }
+
+    #[test]
+    fn remove_clears_timeout() {
+        drop(env_logger::init());
+        let mut timer = TimerWheel::<i32>::new();
+        let now = Instant::now();
+
+        timer.insert(now + ms(100), 3);
+        assert_eq!(timer.next_timeout(), Some(now + ms(100)));
+        assert_eq!(timer.poll(now + ms(200)), Some(3));
+        assert_eq!(timer.next_timeout(), None);
+    }
+}
diff --git a/tests/timer-wheel.rs b/tests/timer-wheel.rs
deleted file mode 100644
index 6b3078ef1..000000000
--- a/tests/timer-wheel.rs
+++ /dev/null
@@ -1,137 +0,0 @@
-extern crate env_logger;
-extern crate futures_mio;
-
-use std::time::{Instant, Duration};
-
-use futures_mio::timer_wheel::TimerWheel;
-
-fn ms(amt: u64) -> Duration {
-    Duration::from_millis(amt)
-}
-
-#[test]
-fn smoke() {
-    drop(env_logger::init());
-    let mut timer = TimerWheel::<i32>::new();
-    let now = Instant::now();
-
-    assert!(timer.poll(now).is_none());
-    assert!(timer.poll(now).is_none());
-
-    timer.insert(now + ms(200), 3);
-
-    assert!(timer.poll(now).is_none());
-    assert!(timer.poll(now + ms(100)).is_none());
-    let res = timer.poll(now + ms(200));
-    assert!(res.is_some());
-    assert_eq!(res.unwrap(), 3);
-}
-
-#[test]
-fn poll_past_done() {
-    drop(env_logger::init());
-    let mut timer = TimerWheel::<i32>::new();
-    let now = Instant::now();
-
-    timer.insert(now + ms(200), 3);
-    let res = timer.poll(now + ms(300));
-    assert!(res.is_some());
-    assert_eq!(res.unwrap(), 3);
-}
-
-#[test]
-fn multiple_ready() {
-    drop(env_logger::init());
-    let mut timer = TimerWheel::<i32>::new();
-    let now = Instant::now();
-
-    timer.insert(now + ms(200), 3);
-    timer.insert(now + ms(201), 4);
-    timer.insert(now + ms(202), 5);
-    timer.insert(now + ms(300), 6);
-    timer.insert(now + ms(301), 7);
-
-    let mut found = Vec::new();
-    while let Some(i) = timer.poll(now + ms(400)) {
-        found.push(i);
-    }
-    found.sort();
-    assert_eq!(found, [3, 4, 5, 6, 7]);
-}
-
-#[test]
-fn poll_now() {
-    drop(env_logger::init());
-    let mut timer = TimerWheel::<i32>::new();
-    let now = Instant::now();
-
-    timer.insert(now, 3);
-    let res = timer.poll(now + ms(100));
-    assert!(res.is_some());
-    assert_eq!(res.unwrap(), 3);
-}
-
-#[test]
-fn cancel() {
-    drop(env_logger::init());
-    let mut timer = TimerWheel::<i32>::new();
-    let now = Instant::now();
-
-    let timeout = timer.insert(now + ms(800), 3);
-    assert!(timer.poll(now + ms(200)).is_none());
-    assert!(timer.poll(now + ms(400)).is_none());
-    assert_eq!(timer.cancel(&timeout), Some(3));
-    assert!(timer.poll(now + ms(600)).is_none());
-    assert!(timer.poll(now + ms(800)).is_none());
-    assert!(timer.poll(now + ms(1000)).is_none());
-}
-
-#[test]
-fn next_timeout() {
-    drop(env_logger::init());
-    let mut timer = TimerWheel::<i32>::new();
-    let now = Instant::now();
-
-    assert!(timer.next_timeout().is_none());
-    timer.insert(now + ms(400), 3);
-    let timeout = timer.next_timeout().expect("wanted a next_timeout");
-    assert_eq!(timeout, now + ms(400));
-
-    timer.insert(now + ms(1000), 3);
-    let timeout = timer.next_timeout().expect("wanted a next_timeout");
-    assert_eq!(timeout, now + ms(400));
-}
-
-#[test]
-fn around_the_boundary() {
-    drop(env_logger::init());
-    let mut timer = TimerWheel::<i32>::new();
-    let now = Instant::now();
-
-    timer.insert(now + ms(199), 3);
-    timer.insert(now + ms(200), 4);
-    timer.insert(now + ms(201), 5);
-    timer.insert(now + ms(251), 6);
-
-    let mut found = Vec::new();
-    while let Some(i) = timer.poll(now + ms(200)) {
-        found.push(i);
-    }
-    found.sort();
-    assert_eq!(found, [3, 4, 5]);
-
-    assert_eq!(timer.poll(now + ms(300)), Some(6));
-    assert_eq!(timer.poll(now + ms(300)), None);
-}
-
-#[test]
-fn remove_clears_timeout() {
-    drop(env_logger::init());
-    let mut timer = TimerWheel::<i32>::new();
-    let now = Instant::now();
-
-    timer.insert(now + ms(100), 3);
-    assert_eq!(timer.next_timeout(), Some(now + ms(100)));
-    assert_eq!(timer.poll(now + ms(200)), Some(3));
-    assert_eq!(timer.next_timeout(), None);
-}