diff --git a/phf/src/lib.rs b/phf/src/lib.rs
index 9eccddbb..b8edb76b 100644
--- a/phf/src/lib.rs
+++ b/phf/src/lib.rs
@@ -104,7 +104,7 @@ impl<K, V> PhfMap<K, V> where K: PhfHash+Eq {
 }
 
 impl<K, V> PhfMap<K, V> {
-    fn get_entry<T>(&self, key: &T, check: |&K| -> bool) -> Option<&(K, V)> where T: PhfHash {
+    fn get_entry<Sized? T>(&self, key: &T, check: |&K| -> bool) -> Option<&(K, V)> where T: PhfHash {
         let (g, f1, f2) = key.phf_hash(self.key);
         let (d1, d2) = self.disps[(g % (self.disps.len() as u32)) as uint];
         let entry = &self.entries[(shared::displace(f1, f2, d1, d2) % (self.entries.len() as u32))
@@ -117,13 +117,13 @@ impl<K, V> PhfMap<K, V> {
     }
 
     /// Like `find`, but can operate on any type that is equivalent to a key.
-    pub fn find_equiv<T>(&self, key: &T) -> Option<&V> where T: PhfHash+Equiv<K> {
+    pub fn find_equiv<Sized? T>(&self, key: &T) -> Option<&V> where T: PhfHash+Equiv<K> {
         self.get_entry(key, |k| key.equiv(k)).map(|e| &e.1)
     }
 
     /// Like `find_key`, but can operate on any type that is equivalent to a
     /// key.
-    pub fn find_key_equiv<T>(&self, key: &T) -> Option<&K> where T: PhfHash+Equiv<K> {
+    pub fn find_key_equiv<Sized? T>(&self, key: &T) -> Option<&K> where T: PhfHash+Equiv<K> {
         self.get_entry(key, |k| key.equiv(k)).map(|e| &e.0)
     }
 }
@@ -304,14 +304,14 @@ impl<T> PhfSet<T> {
     /// Like `contains`, but can operate on any type that is equivalent to a
     /// value
     #[inline]
-    pub fn contains_equiv<U>(&self, key: &U) -> bool where U: PhfHash+Equiv<T> {
+    pub fn contains_equiv<Sized? U>(&self, key: &U) -> bool where U: PhfHash+Equiv<T> {
         self.map.find_equiv(key).is_some()
     }
 
     /// Like `find_key`, but can operate on any type that is equivalent to a
     /// value
     #[inline]
-    pub fn find_key_equiv<U>(&self, key: &U) -> Option<&T> where U: PhfHash+Equiv<T> {
+    pub fn find_key_equiv<Sized? U>(&self, key: &U) -> Option<&T> where U: PhfHash+Equiv<T> {
         self.map.find_key_equiv(key)
     }
 }
@@ -438,7 +438,7 @@ impl<K, V> PhfOrderedMap<K, V> where K: PhfHash+Eq {
 }
 
 impl<K, V> PhfOrderedMap<K, V> {
-    fn find_entry<T>(&self, key: &T, check: |&K| -> bool) -> Option<(uint, &(K, V))>
+    fn find_entry<Sized? T>(&self, key: &T, check: |&K| -> bool) -> Option<(uint, &(K, V))>
             where T: PhfHash {
         let (g, f1, f2) = key.phf_hash(self.key);
         let (d1, d2) = self.disps[(g % (self.disps.len() as u32)) as uint];
@@ -453,19 +453,19 @@ impl<K, V> PhfOrderedMap<K, V> {
     }
 
     /// Like `find`, but can operate on any type that is equivalent to a key.
-    pub fn find_equiv<T>(&self, key: &T) -> Option<&V> where T: PhfHash+Equiv<K> {
+    pub fn find_equiv<Sized? T>(&self, key: &T) -> Option<&V> where T: PhfHash+Equiv<K> {
         self.find_entry(key, |k| key.equiv(k)).map(|(_, e)| &e.1)
     }
 
     /// Like `find_key`, but can operate on any type that is equivalent to a
     /// key.
-    pub fn find_key_equiv<T>(&self, key: &T) -> Option<&K> where T: PhfHash+Equiv<K> {
+    pub fn find_key_equiv<Sized? T>(&self, key: &T) -> Option<&K> where T: PhfHash+Equiv<K> {
         self.find_entry(key, |k| key.equiv(k)).map(|(_, e)| &e.0)
     }
 
     /// Like `find_index`, but can operate on any type that is equivalent to a
     /// key.
-    pub fn find_index_equiv<T>(&self, key: &T) -> Option<uint> where T: PhfHash+Equiv<K> {
+    pub fn find_index_equiv<Sized? T>(&self, key: &T) -> Option<uint> where T: PhfHash+Equiv<K> {
         self.find_entry(key, |k| key.equiv(k)).map(|(i, _)| i)
     }
 
@@ -683,20 +683,20 @@ impl<T> PhfOrderedSet<T> {
     /// Like `contains`, but can operate on any type that is equivalent to a
     /// value
     #[inline]
-    pub fn contains_equiv<U>(&self, key: &U) -> bool where U: PhfHash+Equiv<T> {
+    pub fn contains_equiv<Sized? U>(&self, key: &U) -> bool where U: PhfHash+Equiv<T> {
         self.map.find_equiv(key).is_some()
     }
 
     /// Like `find_key`, but can operate on any type that is equivalent to a
     /// value
     #[inline]
-    pub fn find_key_equiv<U>(&self, key: &U) -> Option<&T> where U: PhfHash+Equiv<T> {
+    pub fn find_key_equiv<Sized? U>(&self, key: &U) -> Option<&T> where U: PhfHash+Equiv<T> {
         self.map.find_key_equiv(key)
     }
 
     /// Like `find_index`, but can operate on any type that is equivalent to a
     /// key.
-    pub fn find_index_equiv<U>(&self, key: &U) -> Option<uint> where U: PhfHash+Equiv<T> {
+    pub fn find_index_equiv<Sized? U>(&self, key: &U) -> Option<uint> where U: PhfHash+Equiv<T> {
         self.map.find_index_equiv(key)
     }
 
diff --git a/phf/tests/test.rs b/phf/tests/test.rs
index 80805a5d..71204252 100644
--- a/phf/tests/test.rs
+++ b/phf/tests/test.rs
@@ -112,7 +112,7 @@ mod map {
         static MAP: PhfMap<&'static str, int> = phf_map!(
             "a" => 0,
         );
-        assert_eq!(Some(&0), MAP.find_equiv(&"a".to_string()[]));
+        assert_eq!(Some(&0), MAP.find_equiv("a".to_string()[]));
     }
 
     #[test]
@@ -248,7 +248,7 @@ mod set {
             "hello",
             "world",
         };
-        assert!(SET.contains_equiv(&"hello".to_string()[]));
+        assert!(SET.contains_equiv("hello".to_string()[]));
     }
 }
 
@@ -289,9 +289,9 @@ mod ordered_map {
         assert_eq!(None, MAP.find_index(&"xyz"));
         assert_eq!(&"baz", MAP.keys().idx(MAP.find_index(&"baz").unwrap()).unwrap());
 
-        assert_eq!(Some(0), MAP.find_index_equiv(&"foo".to_string()[]));
-        assert_eq!(Some(2), MAP.find_index_equiv(&"baz".to_string()[]));
-        assert_eq!(None, MAP.find_index_equiv(&"xyz".to_string()[]));
+        assert_eq!(Some(0), MAP.find_index_equiv("foo".to_string()[]));
+        assert_eq!(Some(2), MAP.find_index_equiv("baz".to_string()[]));
+        assert_eq!(None, MAP.find_index_equiv("xyz".to_string()[]));
     }
 
     #[test]
@@ -349,7 +349,7 @@ mod ordered_map {
         static MAP: PhfOrderedMap<&'static str, int> = phf_ordered_map!(
             "a" => 0,
         );
-        assert_eq!(Some(&0), MAP.find_equiv(&"a".to_string()[]));
+        assert_eq!(Some(&0), MAP.find_equiv("a".to_string()[]));
     }
 }
 
@@ -392,9 +392,9 @@ mod ordered_set {
         assert_eq!(None, SET.find_index(&"xyz"));
         assert_eq!(&"baz", SET.iter().idx(SET.find_index(&"baz").unwrap()).unwrap());
 
-        assert_eq!(Some(0), SET.find_index_equiv(&"foo".to_string()[]));
-        assert_eq!(Some(2), SET.find_index_equiv(&"baz".to_string()[]));
-        assert_eq!(None, SET.find_index_equiv(&"xyz".to_string()[]));
+        assert_eq!(Some(0), SET.find_index_equiv("foo".to_string()[]));
+        assert_eq!(Some(2), SET.find_index_equiv("baz".to_string()[]));
+        assert_eq!(None, SET.find_index_equiv("xyz".to_string()[]));
     }
 
     #[test]
@@ -414,6 +414,6 @@ mod ordered_set {
             "hello",
             "world",
         };
-        assert!(SET.contains_equiv(&"hello".to_string()[]));
+        assert!(SET.contains_equiv("hello".to_string()[]));
     }
 }
diff --git a/shared/mod.rs b/shared/mod.rs
index 5e83c187..d17af213 100644
--- a/shared/mod.rs
+++ b/shared/mod.rs
@@ -1,4 +1,7 @@
 extern crate xxhash;
+extern crate core;
+
+use self::core::kinds::Sized;
 
 #[inline]
 pub fn displace(f1: u32, f2: u32, d1: u32, d2: u32) -> u32 {
@@ -16,7 +19,7 @@ fn split(hash: u64) -> (u32, u32, u32) {
 }
 
 /// A trait implemented by types which can be used in PHF data structures
-pub trait PhfHash {
+pub trait PhfHash for Sized? {
     /// Hashes the value of `self`, factoring in a seed
     fn phf_hash(&self, seed: u64) -> (u32, u32, u32);
 }
@@ -35,6 +38,21 @@ impl<'a> PhfHash for &'a [u8] {
     }
 }
 
+impl PhfHash for str {
+    #[inline]
+    fn phf_hash(&self, seed: u64) -> (u32, u32, u32) {
+        split(xxhash::hash_with_seed(seed, &self))
+    }
+}
+
+impl PhfHash for [u8] {
+    #[inline]
+    fn phf_hash(&self, seed: u64) -> (u32, u32, u32) {
+        split(xxhash::oneshot(self, seed))
+    }
+}
+
+
 macro_rules! sip_impl(
     ($t:ty) => (
         impl PhfHash for $t {