diff --git a/Cargo.lock b/Cargo.lock
index ac52685..f8980cc 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -19,6 +19,7 @@ dependencies = [
  "regex 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_urlencoded 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "tokio-io 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "tokio-proto 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -572,6 +573,17 @@ dependencies = [
  "synom 0.11.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "serde_json"
+version = "1.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "dtoa 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "itoa 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-traits 0.1.40 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.11 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "serde_urlencoded"
 version = "0.5.1"
@@ -893,6 +905,7 @@ dependencies = [
 "checksum serde 1.0.11 (registry+https://github.com/rust-lang/crates.io-index)" = "f7726f29ddf9731b17ff113c461e362c381d9d69433f79de4f3dd572488823e9"
 "checksum serde_derive 1.0.11 (registry+https://github.com/rust-lang/crates.io-index)" = "cf823e706be268e73e7747b147aa31c8f633ab4ba31f115efb57e5047c3a76dd"
 "checksum serde_derive_internals 0.15.1 (registry+https://github.com/rust-lang/crates.io-index)" = "37aee4e0da52d801acfbc0cc219eb1eda7142112339726e427926a6f6ee65d3a"
+"checksum serde_json 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "d243424e06f9f9c39e3cd36147470fd340db785825e367625f79298a6ac6b7ac"
 "checksum serde_urlencoded 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ce0fd303af908732989354c6f02e05e2e6d597152870f2c6990efb0577137480"
 "checksum slab 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "17b4fcaed89ab08ef143da37bc52adbcc04d4a69014f4c1208d6b51f0c47bc23"
 "checksum smallvec 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "4c8cbcd6df1e117c2210e13ab5109635ad68a929fcbb8964dc965b76cb5ee013"
diff --git a/Cargo.toml b/Cargo.toml
index 8316462..8a662ba 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,6 +12,7 @@ tokio-service = "0.1"
 serde_derive = "1.0.0"
 serde = "1.0.0"
 serde_urlencoded = "0.5.0"
+serde_json = "1.0"
 r2d2 = "0.7"
 r2d2-diesel = "0.16"
 regex = "0.2"
diff --git a/src/main.rs b/src/main.rs
index 3cc266c..b948e69 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -11,6 +11,7 @@ extern crate hyper;
 extern crate pulldown_cmark;
 extern crate r2d2;
 extern crate r2d2_diesel;
+extern crate serde_json;
 extern crate serde_urlencoded;
 
 use std::net::SocketAddr;
diff --git a/src/site.rs b/src/site.rs
index e7e5b0f..3beb245 100644
--- a/src/site.rs
+++ b/src/site.rs
@@ -5,6 +5,8 @@ use hyper;
 use hyper::header::ContentType;
 use hyper::mime;
 use hyper::server::*;
+use serde_json;
+use serde_urlencoded;
 
 use models;
 use state::State;
@@ -47,6 +49,7 @@ fn render_markdown(src: &str) -> String {
 
 lazy_static! {
     static ref TEXT_HTML: mime::Mime = "text/html;charset=utf-8".parse().unwrap();
+    static ref APPLICATION_JSON: mime::Mime = "application/json".parse().unwrap();
 }
 
 #[derive(BartDisplay)]
@@ -70,7 +73,7 @@ struct WikiLookup {
 
 impl Lookup for WikiLookup {
     type Resource = ArticleResource;
-    type Error = Box<::std::error::Error + Send>;
+    type Error = Box<::std::error::Error + Send + Sync>;
     type Future = futures::future::FutureResult<Option<Self::Resource>, Self::Error>;
 
     fn lookup(&self, path: &str, _query: Option<&str>, _fragment: Option<&str>) -> Self::Future {
@@ -85,7 +88,7 @@ impl Lookup for WikiLookup {
         if let Ok(article_id) = slug.parse() {
             match self.state.get_article_revision_by_id(article_id) {
                 Ok(Some(article)) => {
-                    futures::finished(Some(ArticleResource::new(article)))
+                    futures::finished(Some(ArticleResource::new(self.state.clone(), article)))
                 },
                 Ok(None) => futures::finished(None),
                 Err(err) => futures::failed(err),
@@ -97,14 +100,13 @@ impl Lookup for WikiLookup {
 }
 
 struct ArticleResource {
+    state: State,
     data: models::ArticleRevision,
 }
 
 impl ArticleResource {
-    fn new(data: models::ArticleRevision) -> Self {
-        Self {
-            data
-        }
+    fn new(state: State, data: models::ArticleRevision) -> Self {
+        Self { state, data }
     }
 }
 
@@ -114,14 +116,14 @@ impl Resource for ArticleResource {
         vec![Options, Head, Get, Put]
     }
 
-    fn head(&self) -> futures::BoxFuture<Response, Box<::std::error::Error + Send>> {
+    fn head(&self) -> futures::BoxFuture<Response, Box<::std::error::Error + Send + Sync>> {
         futures::finished(Response::new()
             .with_status(hyper::StatusCode::Ok)
             .with_header(ContentType(TEXT_HTML.clone()))
         ).boxed()
     }
 
-    fn get(self) -> futures::BoxFuture<Response, Box<::std::error::Error + Send>> {
+    fn get(self) -> futures::BoxFuture<Response, Box<::std::error::Error + Send + Sync>> {
         use chrono::{self, TimeZone, Local};
 
         #[derive(BartDisplay)]
@@ -152,8 +154,52 @@ impl Resource for ArticleResource {
         ).boxed()
     }
 
-    fn put(self, body: &[u8]) -> futures::BoxFuture<Response, Box<::std::error::Error + Send>> {
-        unimplemented!()
+    fn put<S: 'static + futures::Stream<Item=hyper::Chunk, Error=hyper::Error> + Send + Sync>(self, body: S) -> futures::BoxFuture<Response, Box<::std::error::Error + Send + Sync>> {
+        // TODO Check incoming Content-Type
+
+        use chrono::{TimeZone, Local};
+
+        #[derive(Deserialize)]
+        struct UpdateArticle {
+            base_revision: i32,
+            body: String,
+        }
+
+        #[derive(Serialize)]
+        struct PutResponse<'a> {
+            revision: i32,
+            rendered: &'a str,
+            created: &'a str,
+        }
+
+        body
+            .concat2()
+            .map_err(|x| Box::new(x) as Box<::std::error::Error + Send + Sync>)
+            .and_then(move |body| {
+                let update: UpdateArticle = match serde_urlencoded::from_bytes(&body) {
+                    Ok(x) => x,
+                    Err(err) => return futures::finished(Response::new()
+                        .with_status(hyper::StatusCode::BadRequest)
+                        .with_body(format!("{:#?}", err))
+                    ).boxed()
+                };
+
+                let updated = match self.state.update_article(self.data.article_id, update.base_revision, &update.body) {
+                    Ok(x) => x,
+                    Err(x) => return futures::failed(x).boxed(),
+                };
+
+                futures::finished(Response::new()
+                    .with_status(hyper::StatusCode::Ok)
+                    .with_header(ContentType(APPLICATION_JSON.clone()))
+                    .with_body(serde_json::to_string(&PutResponse {
+                        revision: updated.revision,
+                        rendered: &render_markdown(&updated.body),
+                        created: &Local.from_utc_datetime(&updated.created).to_string(),
+                    }).expect("Should never fail"))
+                ).boxed()
+            })
+            .boxed()
     }
 }
 
@@ -179,7 +225,7 @@ impl Site {
             .with_status(hyper::StatusCode::NotFound)
     }
 
-    fn internal_server_error(err: Box<::std::error::Error + Send>) -> Response {
+    fn internal_server_error(err: Box<::std::error::Error + Send + Sync>) -> Response {
         eprintln!("Internal Server Error:\n{:#?}", err);
 
         Response::new()
@@ -210,14 +256,7 @@ impl Service for Site {
                         Options => futures::finished(resource.options()).boxed(),
                         Head => resource.head(),
                         Get => resource.get(),
-                        Put => {
-                            use futures::Stream;
-                            body
-                                .concat2()
-                                .map_err(|x| Box::new(x) as Box<::std::error::Error + Send>)
-                                .and_then(move |body| resource.put(&body))
-                                .boxed()
-                        },
+                        Put => resource.put(body),
                         _ => futures::finished(resource.method_not_allowed()).boxed()
                     }
                 },
diff --git a/src/state.rs b/src/state.rs
index 7ffeb2e..307f583 100644
--- a/src/state.rs
+++ b/src/state.rs
@@ -1,6 +1,7 @@
 use std;
 
 use chrono;
+use diesel;
 use diesel::sqlite::SqliteConnection;
 use diesel::prelude::*;
 use r2d2::Pool;
@@ -13,12 +14,6 @@ pub struct State {
     connection_pool: Pool<ConnectionManager<SqliteConnection>>
 }
 
-#[derive(Deserialize)]
-pub struct UpdateArticle {
-    base_revision: i32,
-    body: String,
-}
-
 pub type Error = Box<std::error::Error + Send + Sync>;
 
 impl State {
@@ -46,4 +41,52 @@ impl State {
             .load::<models::ArticleRevision>(&*self.connection_pool.get()?)?
             .pop())
     }
+
+    pub fn update_article(&self, article_id: i32, base_revision: i32, body: &str) -> Result<models::ArticleRevision, Error> {
+        let conn = self.connection_pool.get()?;
+        conn.transaction(|| {
+            use schema::article_revisions;
+
+            let (latest_revision, title) = article_revisions::table
+                .filter(article_revisions::article_id.eq(article_id))
+                .order(article_revisions::revision.desc())
+                .limit(1)
+                .select((article_revisions::revision, article_revisions::title))
+                .load::<(i32, String)>(&*conn)?
+                .pop()
+                .unwrap_or_else(|| unimplemented!("TODO Missing an error type"));
+
+            if latest_revision != base_revision {
+                // TODO: If it is the same edit repeated, just respond OK
+                // TODO: If there is a conflict, transform the edit to work seamlessly
+                unimplemented!("TODO Missing handling of revision conflicts");
+            }
+            let new_revision = base_revision + 1;
+
+            #[derive(Insertable)]
+            #[table_name="article_revisions"]
+            struct NewRevision<'a> {
+                article_id: i32,
+                revision: i32,
+                title: &'a str,
+                body: &'a str,
+            }
+
+            diesel::insert(&NewRevision {
+                    article_id,
+                    revision: new_revision,
+                    title: &title,
+                    body
+                })
+                .into(article_revisions::table)
+                .execute(&*conn)?;
+
+            Ok(article_revisions::table
+                .filter(article_revisions::article_id.eq(article_id))
+                .filter(article_revisions::revision.eq(new_revision))
+                .load::<models::ArticleRevision>(&*conn)?
+                .pop()
+                .expect("We just inserted this row!"))
+        })
+    }
 }
diff --git a/src/web/resource.rs b/src/web/resource.rs
index 92da2ce..1f15b20 100644
--- a/src/web/resource.rs
+++ b/src/web/resource.rs
@@ -7,13 +7,13 @@ lazy_static! {
     static ref TEXT_PLAIN: mime::Mime = "text/plain;charset=utf-8".parse().unwrap();
 }
 
-type Error = Box<std::error::Error + Send>;
+type Error = Box<std::error::Error + Send + Sync>;
 
 pub trait Resource {
     fn allow(&self) -> Vec<hyper::Method>;
     fn head(&self) -> futures::BoxFuture<server::Response, Error>;
     fn get(self) -> futures::BoxFuture<server::Response, Error>;
-    fn put(self, body: &[u8]) -> futures::BoxFuture<server::Response, Error>;
+    fn put<S: 'static + futures::Stream<Item=hyper::Chunk, Error=hyper::Error> + Send + Sync>(self, body: S) -> futures::BoxFuture<server::Response, Error>;
 
     fn options(&self) -> Response {
         Response::new()
diff --git a/templates/article_revision.html b/templates/article_revision.html
index 6055288..09f9c35 100644
--- a/templates/article_revision.html
+++ b/templates/article_revision.html
@@ -8,7 +8,7 @@
 </div>
 <div class="editor">
     <form action="" method="POST">
-        <input type=hidden name=baseRevision value="{{revision}}">
+        <input type=hidden name=base_revision value="{{revision}}">
         <textarea autocomplete=off name=body>{{raw}}</textarea>
         <textarea autocomplete=off class="shadow-control"></textarea>
         <div class="editor-controls">
@@ -26,10 +26,10 @@
     <dd>{{article_id}}</dd>
 
     <dt>Revision</dt>
-    <dd>{{revision}}</dd>
+    <dd class="revision">{{revision}}</dd>
 
     <dt>Last updated</dt>
-    <dd>{{created}}</dd>
+    <dd class="last-updated">{{created}}</dd>
 </dl>
 </footer>
 
@@ -49,22 +49,29 @@ function queryArgsFromForm(form) {
     return items.join('&');
 }
 
+let hasBeenOpen = false;
 function openEditor() {
     const article = document.querySelector("article");
     const rendered = document.querySelector(".rendered");
     const editor = document.querySelector(".editor");
     const textarea = editor.querySelector('textarea[name="body"]');
     const shadow = editor.querySelector('textarea.shadow-control');
+    const form = editor.querySelector("form");
 
     textarea.style.height = rendered.clientHeight + "px";
 
     article.classList.add('edit');
 
     autosizeTextarea(textarea, shadow);
+
+    textarea.focus();
+
+    if (hasBeenOpen) return;
+    hasBeenOpen = true;
+
     textarea.addEventListener('input', () => autosizeTextarea(textarea, shadow));
     window.addEventListener('resize', () => autosizeTextarea(textarea, shadow));
 
-    const form = editor.querySelector("form");
     form.addEventListener("submit", function (ev) {
         (async function () {
             ev.preventDefault();
@@ -86,6 +93,13 @@ function openEditor() {
 
             if (!response.ok) throw new Error("Unexpected status code (" + response.status + ")");
 
+            const result = await response.json();
+            form.elements.base_revision.value = result.revision;
+            document.querySelector("footer .revision").textContent = result.revision;
+            document.querySelector("footer .last-updated").textContent = result.created;
+            rendered.innerHTML = result.rendered;
+            article.classList.remove('edit');
+
             textarea.disabled = false;
         }()
         .catch(err => {
@@ -94,8 +108,6 @@ function openEditor() {
             alert(err);
         }));
     });
-
-    textarea.focus();
 }
 
 document