diff --git a/README.md b/README.md
index ab1f7110e4..d8edbb4019 100644
--- a/README.md
+++ b/README.md
@@ -338,10 +338,12 @@ TODO
 
  - [x] Change `context` to `contexts`.
  - [x] Change `contexts` to `context`....
- - [] Figure out what a `Context` will be
+ - [x] Figure out what a `Context` will be
  - [x] Implement hack to make `global` inherit from `self`
  - [x] Define on `self.registerModel(factory: (c) => Model)` protocol
  - [x] Describe `contexts`
+ - [x] Implement loading a model from a file.
+ - [ ] Document `suggestions`
  - [ ] make simple `index.html` that demos a dummy model
  - [ ] make an `error` initialization message.
  - [ ] TypeScript!
diff --git a/index.js b/index.js
index d82af000c3..174b7208e5 100644
--- a/index.js
+++ b/index.js
@@ -21,7 +21,7 @@ class LMLayer {
   /**
    * [async] Waits for the model's initialization.
    */
-  initialize(_acceptConfiguration) {
+  initialize({model, configuration }) {
     if (this._configuration) {
       return Promise.resolve(this._configuration);
     }
@@ -30,9 +30,11 @@ class LMLayer {
     // _onMessage() will resolve this Promise.
     return new Promise((resolve, _reject) => {
       this._cast('initialize', {
+        model, 
         configuration: {
           maxLeftContextCodeUnits: 32,
           supportsRightContexts: false,
+          ...configuration
         }
       });
       this._resolveInitialized = resolve;
diff --git a/lmlayer.js b/lmlayer.js
index aa327dc169..04bd2f2307 100644
--- a/lmlayer.js
+++ b/lmlayer.js
@@ -52,7 +52,7 @@ function onMessageWhenUninitialized(event) {
   }
 
   // Import the model.
-  let model = loadModel(configuration.path, configuration);
+  let model = loadModel(event.data.model, configuration);
   transitionToReadyState(model);
 
   // Ready! Send desired configuration.
@@ -69,7 +69,7 @@ function transitionToReadyState(model) {
    * Responds to `predict` messages with a `suggestions` message.
    */
   onMessage = function onMessageWhenReady(event) {
-    const {message, token} = event.data;
+    const {message, token, transform, context} = event.data;
 
     if (message !== 'predict') {
       throw new Error('invalid message');
@@ -82,10 +82,9 @@ function transitionToReadyState(model) {
       return;
     }
 
-    // TODO: rip contexts out of message.
-    let rawSuggestions = model.predict();
+    let rawSuggestions = model.predict(context, transform);
 
-    // Sort in-place according to weight.
+    // Sort in-place according to weight, ascending.
     rawSuggestions.sort((a, b) => a.weight - b.weight);
 
     // Convert the internal suggestion format to the one required by the keyboard.
@@ -114,8 +113,8 @@ function cast(message, parameters) {
 /**
  * Loads the model from a separate file.
  */
-function loadModel(_path /* : string */, configuration /* : Configuration */) {
-  importScripts('./models/en-x-test-derek.js');
+function loadModel(path /* : string */, configuration /* : Configuration */) {
+  importScripts(path);
   /**
    * The model MUST call registerModel() which ultimately defines
    * createModel() to a function.
diff --git a/models/en-x-test-teapot.js b/models/en-x-test-teapot.js
new file mode 100644
index 0000000000..a8f9bfac4e
--- /dev/null
+++ b/models/en-x-test-teapot.js
@@ -0,0 +1,33 @@
+/**
+ * This is a test model that simply returns "teapot" when given the context of
+ * «I'm a little ».
+ */
+registerModel(function () {
+  return {
+    predict(context, transform) {
+      return [
+        {
+          transform: {
+            insert: 'teapot',
+            deleteLeft: transform.insert.length,
+            deleteRight: 0,
+          },
+          displayAs: '🍵',
+          weight: 0.00,
+        }
+      ];
+
+      /* TODO:
+      if (context.wordsLeft === ["I'm", "a", "little"] &&
+        transform.insert === 't') {
+      }
+
+      return [];
+      */
+    },
+
+    configuration: {
+    }
+  };
+});
+/*global registerModel*/
diff --git a/test.js b/test.js
index c5ad72026f..8a8a18d6fe 100644
--- a/test.js
+++ b/test.js
@@ -11,7 +11,7 @@ test('It provide context to LMLayer', async t => {
   const lm = new LMLayer;
 
   // Wait for the language model to initialize and declare its configuration.
-  let configuration = await lm.initialize({ model: 'en-x-derek' });
+  let configuration = await lm.initialize({ model: './models/en-x-test-derek.js' });
   // The model should as for 32 code units of context to the left of the
   // cursor.
   t.is(configuration.leftContextCodeUnits, 32);
@@ -46,7 +46,7 @@ test('It should reject when predictions crash', async t => {
   t.plan(1);
 
   const lm = new LMLayer;
-  await lm.initialize({ model: 'en-x-derek' });
+  await lm.initialize({ model: './models/en-x-test-derek.js' });
 
   try {
     await lm.predict({