diff --git a/src/ser.rs b/src/ser/impls.rs
similarity index 69%
rename from src/ser.rs
rename to src/ser/impls.rs
index 26fc91cf..babfa5ea 100644
--- a/src/ser.rs
+++ b/src/ser/impls.rs
@@ -3,188 +3,14 @@ use std::collections::{BTreeMap, BTreeSet, HashMap, HashSet, VecMap};
 use std::hash::Hash;
 use std::path;
 use std::rc::Rc;
-use std::str;
 use std::sync::Arc;
 
-///////////////////////////////////////////////////////////////////////////////
-
-pub trait Serialize {
-    fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error>
-        where S: Serializer;
-}
-
-///////////////////////////////////////////////////////////////////////////////
-
-pub trait Serializer {
-    type Error;
-
-    fn visit_bool(&mut self, v: bool) -> Result<(), Self::Error>;
-
-    #[inline]
-    fn visit_isize(&mut self, v: isize) -> Result<(), Self::Error> {
-        self.visit_i64(v as i64)
-    }
-
-    #[inline]
-    fn visit_i8(&mut self, v: i8) -> Result<(), Self::Error> {
-        self.visit_i64(v as i64)
-    }
-
-    #[inline]
-    fn visit_i16(&mut self, v: i16) -> Result<(), Self::Error> {
-        self.visit_i64(v as i64)
-    }
-
-    #[inline]
-    fn visit_i32(&mut self, v: i32) -> Result<(), Self::Error> {
-        self.visit_i64(v as i64)
-    }
-
-    #[inline]
-    fn visit_i64(&mut self, v: i64) -> Result<(), Self::Error>;
-
-    #[inline]
-    fn visit_usize(&mut self, v: usize) -> Result<(), Self::Error> {
-        self.visit_u64(v as u64)
-    }
-
-    #[inline]
-    fn visit_u8(&mut self, v: u8) -> Result<(), Self::Error> {
-        self.visit_u64(v as u64)
-    }
-
-    #[inline]
-    fn visit_u16(&mut self, v: u16) -> Result<(), Self::Error> {
-        self.visit_u64(v as u64)
-    }
-
-    #[inline]
-    fn visit_u32(&mut self, v: u32) -> Result<(), Self::Error> {
-        self.visit_u64(v as u64)
-    }
-
-    #[inline]
-    fn visit_u64(&mut self, v: u64) -> Result<(), Self::Error>;
-
-    #[inline]
-    fn visit_f32(&mut self, v: f32) -> Result<(), Self::Error> {
-        self.visit_f64(v as f64)
-    }
-
-    fn visit_f64(&mut self, v: f64) -> Result<(), Self::Error>;
-
-    /// `visit_char` serializes a character. By default it serializes it as a `&str` containing a
-    /// single character.
-    #[inline]
-    fn visit_char(&mut self, v: char) -> Result<(), Self::Error> {
-        // The unwraps in here should be safe.
-        let mut s = &mut [0; 4];
-        let len = v.encode_utf8(s).unwrap();
-        self.visit_str(str::from_utf8(&s[..len]).unwrap())
-    }
-
-    /// `visit_str` serializes a `&str`.
-    fn visit_str(&mut self, value: &str) -> Result<(), Self::Error>;
-
-    /// `visit_bytes` is a hook that enables those serialization formats that support serializing
-    /// byte slices separately from generic arrays. By default it serializes as a regular array. 
-    #[inline]
-    fn visit_bytes(&mut self, value: &[u8]) -> Result<(), Self::Error> {
-        self.visit_seq(SeqIteratorVisitor::new(value.iter(), Some(value.len())))
-    }
-
-    fn visit_unit(&mut self) -> Result<(), Self::Error>;
-
-    #[inline]
-    fn visit_named_unit(&mut self, _name: &str) -> Result<(), Self::Error> {
-        self.visit_unit()
-    }
-
-    #[inline]
-    fn visit_enum_unit(&mut self,
-                       _name: &str,
-                       _variant: &str) -> Result<(), Self::Error> {
-        self.visit_unit()
-    }
-
-    fn visit_none(&mut self) -> Result<(), Self::Error>;
-
-    fn visit_some<V>(&mut self, value: V) -> Result<(), Self::Error>
-        where V: Serialize;
-
-    fn visit_seq<V>(&mut self, visitor: V) -> Result<(), Self::Error>
-        where V: SeqVisitor;
-
-    #[inline]
-    fn visit_named_seq<V>(&mut self,
-                          _name: &'static str,
-                          visitor: V) -> Result<(), Self::Error>
-        where V: SeqVisitor,
-    {
-        self.visit_seq(visitor)
-    }
-
-    #[inline]
-    fn visit_enum_seq<V>(&mut self,
-                         _name: &'static str,
-                         _variant: &'static str,
-                         visitor: V) -> Result<(), Self::Error>
-        where V: SeqVisitor,
-    {
-        self.visit_seq(visitor)
-    }
-
-    fn visit_seq_elt<T>(&mut self, value: T) -> Result<(), Self::Error>
-        where T: Serialize;
-
-    fn visit_map<V>(&mut self, visitor: V) -> Result<(), Self::Error>
-        where V: MapVisitor;
-
-    #[inline]
-    fn visit_named_map<V>(&mut self,
-                          _name: &'static str,
-                          visitor: V) -> Result<(), Self::Error>
-        where V: MapVisitor,
-    {
-        self.visit_map(visitor)
-    }
-
-    #[inline]
-    fn visit_enum_map<V>(&mut self,
-                          _name: &'static str,
-                          _variant: &'static str,
-                          visitor: V) -> Result<(), Self::Error>
-        where V: MapVisitor,
-    {
-        self.visit_map(visitor)
-    }
-
-    fn visit_map_elt<K, V>(&mut self, key: K, value: V) -> Result<(), Self::Error>
-        where K: Serialize,
-              V: Serialize;
-}
-
-pub trait SeqVisitor {
-    fn visit<S>(&mut self, serializer: &mut S) -> Result<Option<()>, S::Error>
-        where S: Serializer;
-
-    /// Return the length of the sequence if known.
-    #[inline]
-    fn len(&self) -> Option<usize> {
-        None
-    }
-}
-
-pub trait MapVisitor {
-    fn visit<S>(&mut self, serializer: &mut S) -> Result<Option<()>, S::Error>
-        where S: Serializer;
-
-    /// Return the length of the map if known.
-    #[inline]
-    fn len(&self) -> Option<usize> {
-        None
-    }
-}
+use super::{
+    Serialize,
+    Serializer,
+    SeqVisitor,
+    MapVisitor,
+};
 
 ///////////////////////////////////////////////////////////////////////////////
 
diff --git a/src/ser/mod.rs b/src/ser/mod.rs
new file mode 100644
index 00000000..3c0e79eb
--- /dev/null
+++ b/src/ser/mod.rs
@@ -0,0 +1,183 @@
+use std::str;
+
+pub mod impls;
+
+///////////////////////////////////////////////////////////////////////////////
+
+pub trait Serialize {
+    fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error>
+        where S: Serializer;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+pub trait Serializer {
+    type Error;
+
+    fn visit_bool(&mut self, v: bool) -> Result<(), Self::Error>;
+
+    #[inline]
+    fn visit_isize(&mut self, v: isize) -> Result<(), Self::Error> {
+        self.visit_i64(v as i64)
+    }
+
+    #[inline]
+    fn visit_i8(&mut self, v: i8) -> Result<(), Self::Error> {
+        self.visit_i64(v as i64)
+    }
+
+    #[inline]
+    fn visit_i16(&mut self, v: i16) -> Result<(), Self::Error> {
+        self.visit_i64(v as i64)
+    }
+
+    #[inline]
+    fn visit_i32(&mut self, v: i32) -> Result<(), Self::Error> {
+        self.visit_i64(v as i64)
+    }
+
+    #[inline]
+    fn visit_i64(&mut self, v: i64) -> Result<(), Self::Error>;
+
+    #[inline]
+    fn visit_usize(&mut self, v: usize) -> Result<(), Self::Error> {
+        self.visit_u64(v as u64)
+    }
+
+    #[inline]
+    fn visit_u8(&mut self, v: u8) -> Result<(), Self::Error> {
+        self.visit_u64(v as u64)
+    }
+
+    #[inline]
+    fn visit_u16(&mut self, v: u16) -> Result<(), Self::Error> {
+        self.visit_u64(v as u64)
+    }
+
+    #[inline]
+    fn visit_u32(&mut self, v: u32) -> Result<(), Self::Error> {
+        self.visit_u64(v as u64)
+    }
+
+    #[inline]
+    fn visit_u64(&mut self, v: u64) -> Result<(), Self::Error>;
+
+    #[inline]
+    fn visit_f32(&mut self, v: f32) -> Result<(), Self::Error> {
+        self.visit_f64(v as f64)
+    }
+
+    fn visit_f64(&mut self, v: f64) -> Result<(), Self::Error>;
+
+    /// `visit_char` serializes a character. By default it serializes it as a `&str` containing a
+    /// single character.
+    #[inline]
+    fn visit_char(&mut self, v: char) -> Result<(), Self::Error> {
+        // The unwraps in here should be safe.
+        let mut s = &mut [0; 4];
+        let len = v.encode_utf8(s).unwrap();
+        self.visit_str(str::from_utf8(&s[..len]).unwrap())
+    }
+
+    /// `visit_str` serializes a `&str`.
+    fn visit_str(&mut self, value: &str) -> Result<(), Self::Error>;
+
+    /// `visit_bytes` is a hook that enables those serialization formats that support serializing
+    /// byte slices separately from generic arrays. By default it serializes as a regular array. 
+    #[inline]
+    fn visit_bytes(&mut self, value: &[u8]) -> Result<(), Self::Error> {
+        self.visit_seq(impls::SeqIteratorVisitor::new(value.iter(), Some(value.len())))
+    }
+
+    fn visit_unit(&mut self) -> Result<(), Self::Error>;
+
+    #[inline]
+    fn visit_named_unit(&mut self, _name: &str) -> Result<(), Self::Error> {
+        self.visit_unit()
+    }
+
+    #[inline]
+    fn visit_enum_unit(&mut self,
+                       _name: &str,
+                       _variant: &str) -> Result<(), Self::Error> {
+        self.visit_unit()
+    }
+
+    fn visit_none(&mut self) -> Result<(), Self::Error>;
+
+    fn visit_some<V>(&mut self, value: V) -> Result<(), Self::Error>
+        where V: Serialize;
+
+    fn visit_seq<V>(&mut self, visitor: V) -> Result<(), Self::Error>
+        where V: SeqVisitor;
+
+    #[inline]
+    fn visit_named_seq<V>(&mut self,
+                          _name: &'static str,
+                          visitor: V) -> Result<(), Self::Error>
+        where V: SeqVisitor,
+    {
+        self.visit_seq(visitor)
+    }
+
+    #[inline]
+    fn visit_enum_seq<V>(&mut self,
+                         _name: &'static str,
+                         _variant: &'static str,
+                         visitor: V) -> Result<(), Self::Error>
+        where V: SeqVisitor,
+    {
+        self.visit_seq(visitor)
+    }
+
+    fn visit_seq_elt<T>(&mut self, value: T) -> Result<(), Self::Error>
+        where T: Serialize;
+
+    fn visit_map<V>(&mut self, visitor: V) -> Result<(), Self::Error>
+        where V: MapVisitor;
+
+    #[inline]
+    fn visit_named_map<V>(&mut self,
+                          _name: &'static str,
+                          visitor: V) -> Result<(), Self::Error>
+        where V: MapVisitor,
+    {
+        self.visit_map(visitor)
+    }
+
+    #[inline]
+    fn visit_enum_map<V>(&mut self,
+                          _name: &'static str,
+                          _variant: &'static str,
+                          visitor: V) -> Result<(), Self::Error>
+        where V: MapVisitor,
+    {
+        self.visit_map(visitor)
+    }
+
+    fn visit_map_elt<K, V>(&mut self, key: K, value: V) -> Result<(), Self::Error>
+        where K: Serialize,
+              V: Serialize;
+}
+
+pub trait SeqVisitor {
+    fn visit<S>(&mut self, serializer: &mut S) -> Result<Option<()>, S::Error>
+        where S: Serializer;
+
+    /// Return the length of the sequence if known.
+    #[inline]
+    fn len(&self) -> Option<usize> {
+        None
+    }
+}
+
+pub trait MapVisitor {
+    fn visit<S>(&mut self, serializer: &mut S) -> Result<Option<()>, S::Error>
+        where S: Serializer;
+
+    /// Return the length of the map if known.
+    #[inline]
+    fn len(&self) -> Option<usize> {
+        None
+    }
+}