diff --git a/.gitignore b/.gitignore
index 63d1ee48..c4dfc9b3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -16,3 +16,6 @@ db.sql
 # Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
 # More information here http://doc.crates.io/guide.html#cargotoml-vs-cargolock
 Cargo.lock
+
+# Scratch list of items that need to get done.
+_TODO
diff --git a/Cargo.toml b/Cargo.toml
index c4bf6de3..c3f47965 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,5 +1,8 @@
 [workspace]
 members = [
+  "lib/",
+  "codegen/",
+  "contrib/",
   "examples/cookies",
   "examples/errors",
   "examples/extended_validation",
@@ -18,4 +21,8 @@ members = [
   "examples/testing",
   "examples/from_request",
   "examples/stream",
+  "examples/json",
 ]
+
+[replace]
+"aster:0.26.1" = { git = "https://github.com/jchlapinski/aster" }
diff --git a/contrib/Cargo.toml b/contrib/Cargo.toml
new file mode 100644
index 00000000..b8a1308b
--- /dev/null
+++ b/contrib/Cargo.toml
@@ -0,0 +1,16 @@
+[package]
+name = "rocket_contrib"
+version = "0.0.8"
+authors = ["Sergio Benitez <sb@sergio.bz>"]
+
+[features]
+default = ["json"]
+json = ["serde", "serde_json"]
+
+[dependencies]
+rocket = { path = "../lib/" }
+log = "*"
+
+# JSON module dependencies
+serde = { version = "*", optional = true }
+serde_json = { version = "*", optional = true }
diff --git a/contrib/src/json/mod.rs b/contrib/src/json/mod.rs
new file mode 100644
index 00000000..67cd4f7c
--- /dev/null
+++ b/contrib/src/json/mod.rs
@@ -0,0 +1,131 @@
+extern crate serde;
+extern crate serde_json;
+
+use std::ops::{Deref, DerefMut};
+
+use rocket::request::{Request, FromRequest};
+use rocket::response::{header, Responder, Outcome, FreshHyperResponse};
+use rocket::response::mime::{Mime, TopLevel, SubLevel};
+
+use self::serde::{Serialize, Deserialize};
+use self::serde_json::Error as JSONError;
+
+/// The JSON datatype, which implements both `FromRequest` and `Responder`. This
+/// type allows you to trivially consume and respond with JSON in your Rocket
+/// application.
+///
+/// If you're receiving JSON data, simple add a `JSON<T>` type to your function
+/// signature where `T` is some type you'd like to parse from JSON. `T` must
+/// implement `Deserialize` from [Serde](https://github.com/serde-rs/json). The
+/// data is parsed from the HTTP request body.
+///
+/// ```rust,ignore
+/// #[post("/users/", format = "application/json")]
+/// fn new_user(user: JSON<User>) {
+///     ...
+/// }
+/// ```
+/// You don't _need_ to use `format = "application/json"`, but it _may_ be what
+/// you want. Using `format = application/json` means that any request that
+/// doesn't specify "application/json" as its first `Accept:` header parameter
+/// will not be routed to this handler.
+///
+/// If you're responding with JSON data, return a `JSON<T>` type, where `T`
+/// implements implements `Serialize` from
+/// [Serde](https://github.com/serde-rs/json). The content type is set to
+/// `application/json` automatically.
+///
+/// ```rust,ignore
+/// #[get("/users/<id>")]
+/// fn user(id: usize) -> JSON<User> {
+///     let user_from_id = User::from(id);
+///     ...
+///     JSON(user_from_id)
+/// }
+/// ```
+///
+pub struct JSON<T>(pub T);
+
+impl<T> JSON<T> {
+    /// Consumes the JSON wrapper and returns the wrapped item.
+    ///
+    /// # Example
+    /// ```rust
+    /// # use rocket_contrib::JSON;
+    /// let string = "Hello".to_string();
+    /// let my_json = JSON(string);
+    /// assert_eq!(my_json.unwrap(), "Hello".to_string());
+    /// ```
+    pub fn unwrap(self) -> T {
+        self.0
+    }
+}
+
+impl<'r, 'c, T: Deserialize> FromRequest<'r, 'c> for JSON<T> {
+    type Error = JSONError;
+    fn from_request(request: &'r Request<'c>) -> Result<Self, Self::Error> {
+        Ok(JSON(serde_json::from_slice(request.data.as_slice())?))
+    }
+}
+
+impl<T: Serialize> Responder for JSON<T> {
+    fn respond<'a>(&mut self, mut res: FreshHyperResponse<'a>) -> Outcome<'a> {
+        let mime = Mime(TopLevel::Application, SubLevel::Json, vec![]);
+        res.headers_mut().set(header::ContentType(mime));
+        match serde_json::to_string(&self.0) {
+            Ok(mut json_string) => json_string.respond(res),
+            Err(e) => {
+                error_!("JSON failed to serialize: {:?}", e);
+                Outcome::FailStop
+            }
+        }
+    }
+}
+
+impl<T> Deref for JSON<T> {
+    type Target = T;
+
+    fn deref<'a>(&'a self) -> &'a T {
+        &self.0
+    }
+}
+
+impl<T> DerefMut for JSON<T> {
+    fn deref_mut<'a>(&'a mut self) -> &'a mut T {
+        &mut self.0
+    }
+}
+
+/// A nice little macro to create simple HashMaps. Really convenient for
+/// returning ad-hoc JSON messages.
+///
+/// # Examples
+///
+/// ```
+/// # #[macro_use] extern crate rocket_contrib;
+/// use std::collections::HashMap;
+/// # fn main() {
+/// let map: HashMap<&str, usize> = map! {
+///     "status" => 0,
+///     "count" => 100
+/// };
+///
+/// assert_eq!(map.len(), 2);
+/// assert_eq!(map.get("status"), Some(&0));
+/// assert_eq!(map.get("count"), Some(&100));
+/// # }
+/// ```
+#[macro_export]
+macro_rules! map {
+    ($($key:expr => $value:expr),+) => ({
+        use std::collections::HashMap;
+        let mut map = HashMap::new();
+        $(map.insert($key, $value);)+
+        map
+    });
+
+    ($($key:expr => $value:expr),+,) => {
+        map!($($key => $value),+)
+    };
+}
+
diff --git a/contrib/src/lib.rs b/contrib/src/lib.rs
new file mode 100644
index 00000000..923b261b
--- /dev/null
+++ b/contrib/src/lib.rs
@@ -0,0 +1,40 @@
+#![feature(question_mark)]
+
+//! This crate contains officially sanctioned contributor libraries that provide
+//! functionality commonly used by Rocket applications.
+//!
+//! These libraries are always kept in-sync with the core Rocket library. They
+//! provide common, but not fundamental, abstractions to be used by Rocket
+//! applications. In particular, contributor libraries typically export types
+//! that implement the `FromRequest` trait, `Responder` trait, or both.
+//!
+//! Each module in this library is held behind a feature flag, with the most
+//! common modules exposed by default. The present feature list is below, with
+//! an asterisk next to the features that are enabled by default:
+//!
+//! * json*
+//!
+//! The recommend way to include features from this crate via Cargo in your
+//! project is by adding a `[dependencies.rocket_contrib]` section to your
+//! `Cargo.toml` file, setting `default-features` to false, and specifying
+//! features manually. For example, to use the JSON module, you would add:
+//!
+//! ```rust,ignore
+//! [dependencies.rocket_contrib]
+//! version = "*"
+//! default-features = false
+//! features = ["json"]
+//! ```
+//!
+//! This crate is expected to grow with time, bringing in outside crates to be
+//! officially supported by Rocket.
+
+#[macro_use] extern crate log;
+#[macro_use] extern crate rocket;
+
+#[cfg_attr(feature = "json", macro_use)]
+#[cfg(feature = "json")]
+mod json;
+
+#[cfg(feature = "json")]
+pub use json::JSON;
diff --git a/examples/json/Cargo.toml b/examples/json/Cargo.toml
new file mode 100644
index 00000000..bdfefb7d
--- /dev/null
+++ b/examples/json/Cargo.toml
@@ -0,0 +1,18 @@
+[package]
+name = "json"
+version = "0.0.1"
+authors = ["Sergio Benitez <sb@sergio.bz>"]
+workspace = "../../"
+
+[dependencies]
+rocket = { path = "../../lib" }
+rocket_codegen = { path = "../../codegen" }
+serde = "*"
+serde_json = "*"
+serde_macros = "*"
+lazy_static = "*"
+
+[dependencies.rocket_contrib]
+path = "../../contrib"
+default-features = false
+features = ["json"]
diff --git a/examples/json/src/main.rs b/examples/json/src/main.rs
new file mode 100644
index 00000000..3b9483d3
--- /dev/null
+++ b/examples/json/src/main.rs
@@ -0,0 +1,92 @@
+#![feature(plugin, custom_derive)]
+#![plugin(rocket_codegen, serde_macros)]
+
+#[macro_use] extern crate lazy_static;
+#[macro_use] extern crate rocket_contrib;
+extern crate rocket;
+extern crate serde_json;
+
+use rocket::{Rocket, Request, Error};
+use rocket_contrib::JSON;
+use std::collections::HashMap;
+use std::sync::Mutex;
+
+// The type to represent the ID of a message.
+type ID = usize;
+type SimpleMap = HashMap<&'static str, &'static str>;
+
+// We're going to store all of the messages here. No need for a DB.
+lazy_static! {
+    static ref MAP: Mutex<HashMap<ID, String>> = Mutex::new(HashMap::new());
+}
+
+#[derive(Serialize, Deserialize)]
+struct Message {
+    id: Option<ID>,
+    contents: String
+}
+
+// TODO: This example can be improved by using `route` with muliple HTTP verbs.
+// To be precise, put/post could/should look like:
+// #[route(PUT, POST, path = "/<id>", format = "application/json")]
+// fn f(method: Method, id: ID, message: JSON<Message>) -> Option<JSON<SimpleMap>> {
+//     let mut hashmap = MAP.lock().unwrap();
+//     let exists = hashmap.contains_key(&id);
+//     if method == Method::Put && exists || method == Method::Post && !exists {
+//         hashmap.insert(id, message.0.contents);
+//         return Ok(JSON(map!{ "status" => "ok" }))
+//     }
+//
+//     None
+// }
+
+#[post("/<id>", format = "application/json")]
+fn new(id: ID, message: JSON<Message>) -> JSON<SimpleMap> {
+    let mut hashmap = MAP.lock().unwrap();
+    if hashmap.contains_key(&id) {
+        JSON(map!{
+            "status" => "error",
+            "reason" => "ID exists. Try put."
+        })
+    } else {
+        hashmap.insert(id, message.0.contents);
+        JSON(map!{ "status" => "ok" })
+    }
+}
+
+#[put("/<id>", format = "application/json")]
+fn update(id: ID, message: JSON<Message>) -> Option<JSON<SimpleMap>> {
+    let mut hashmap = MAP.lock().unwrap();
+    if hashmap.contains_key(&id) {
+        hashmap.insert(id, message.0.contents);
+        Some(JSON(map!{ "status" => "ok" }))
+    } else {
+        None
+    }
+}
+
+#[get("/<id>", format = "application/json")]
+fn get(id: ID) -> Option<JSON<Message>> {
+    let hashmap = MAP.lock().unwrap();
+    hashmap.get(&id).map(|contents| {
+        JSON(Message {
+            id: Some(id),
+            contents: contents.clone()
+        })
+    })
+}
+
+#[error(404)]
+fn not_found<'r>(_: Error, _: &'r Request<'r>) -> JSON<SimpleMap> {
+    JSON(map! {
+        "status" => "error",
+        "reason" => "Resource was not found."
+    })
+}
+
+fn main() {
+    let mut rocket = Rocket::new("localhost", 8000);
+    rocket.mount("/message", routes![new, update, get]);
+    rocket.catch(errors![not_found]);
+    rocket.launch();
+}
diff --git a/lib/src/response/stream.rs b/lib/src/response/stream.rs
index 20635510..9838bb2c 100644
--- a/lib/src/response/stream.rs
+++ b/lib/src/response/stream.rs
@@ -13,7 +13,7 @@ impl<T: Read> Stream<T> {
 }
 
 impl<T: Read> Responder for Stream<T> {
-    fn respond<'a>(&mut self, mut res: FreshHyperResponse<'a>) -> Outcome<'a> {
+    fn respond<'a>(&mut self, res: FreshHyperResponse<'a>) -> Outcome<'a> {
         let mut stream = res.start().unwrap();
         let mut buffer = [0; CHUNK_SIZE];
         let mut complete = false;
diff --git a/scripts/test.sh b/scripts/test.sh
index 3e7f453c..3b4d4e0a 100755
--- a/scripts/test.sh
+++ b/scripts/test.sh
@@ -4,6 +4,7 @@ set -e
 EXAMPLES_DIR="examples"
 LIB_DIR="lib"
 CODEGEN_DIR="codegen"
+CONTRIB_DIR="contrib"
 
 # Add Cargo to PATH.
 export PATH=${HOME}/.cargo/bin:${PATH}
@@ -26,6 +27,7 @@ function build_and_test() {
 
 build_and_test $LIB_DIR
 build_and_test $CODEGEN_DIR
+build_and_test $CONTRIB_DIR
 
 for file in ${EXAMPLES_DIR}/*; do
   if [ -d "${file}" ]; then