diff --git a/CHANGELOG b/CHANGELOG
deleted file mode 100644
--- a/CHANGELOG
+++ /dev/null
@@ -1,40 +0,0 @@
-2012-07-26
-0.1.1.0: Lots of documentation updates, some runtime fixes, some more examples, tail-call optimization prototype.
-
-cf6b848 Add analytics to .cabal.
-13b8d0e Fix types for ghc.
-4a021a3 Use continue (for now) for TCO (refs #19).
-b43220c Tail recursive optimization prototype (refs #19).
-137a702 Tail recursive example doc.
-6ec356b Ref example.
-e10023c fromInteger/fromRational in the runtime (closes #20).
-7527aaa Add missing operators to Prelude and built-ins list (closes #16).
-9ce6915 Throw error about unsupported `where' (closes #17).
-406067c Fix silly enumFromTo mistake.
-8c37842 A test-case that tail-recursive functions run iteratively.
-1791e68 Optimize constant patterns slightly, shaves off some time.
-f016d01 Add Fay.Show (preliminary implementation).
-66cf298 Add data/show example.
-486c4f3 Add note about generating docs.
-15fd56c Add note that you need nodejs installed to run the tests.
-ae207b7 Include google analytics in docs and generate index.html rather than home.html.
-07f7f4a Updated dom example with onload handler.
-e702218 Remove max-width to fix firefox.
-aa5dc2b Mention minifying slightly in docs.
-e53addc Remove language-javascript dependency.
-f976ff6 Remove non-ascii character in runtime.js
-2abd59d Don't print counts in fay-tests.
-c0127c3 Add small note about livescript.
-0d35867 Added fork on github for docs.
-f6a0d62 Use === instead of == for jseq (closes #6).
-7d1a382 Some word break on the pre's.
-37e3d53 Rename modules from Main to X (closes #5).
-6734221 Ignore more stuff.
-4479709 Toggle examples.
-3ddf795 Put examples side-by-side (closes #3).
-5ae7cca s/strict/proper to avoid confusion.
-a482a5b Convert from function expression assignments to function definitions
-
-2012-07-21
-0.1.0.0: First version.
-
diff --git a/docs/home.hs b/docs/home.hs
--- a/docs/home.hs
+++ b/docs/home.hs
@@ -25,16 +25,6 @@
     indentAndHighlight
     setupExpanders
     setupTableOfContents
-    body <- query ".subheadline"
-    addClassWith (\i f -> do alert (show i)
-                             alert f
-                             return f)
-                 body
-    return ()
-
-addClassWith :: (Double -> String -> Fay String) -> JQuery -> Fay JQuery
-addClassWith = ffi "%2.addClass(function(x,i){ return %1(x,Fay$$list(i)); })" FayNone
-
 
 -- | Setup highlighting/code re-indenting.
 indentAndHighlight :: Fay ()
diff --git a/examples/alert.hs b/examples/alert.hs
--- a/examples/alert.hs
+++ b/examples/alert.hs
@@ -9,5 +9,5 @@
 main = alert "Hello, World!"
 
 -- | Alert using window.alert.
-alert :: Foreign a => a -> Fay ()
-alert = ffi "window.alert(%1)" FayNone
+alert :: String -> Fay ()
+alert = ffi "window.alert(%1)"
diff --git a/examples/canvaswater.hs b/examples/canvaswater.hs
--- a/examples/canvaswater.hs
+++ b/examples/canvaswater.hs
@@ -55,11 +55,11 @@
 
 -- | Add an event listener to an element.
 addEventListener :: (Foreign a,Eventable a) => a -> String -> Fay () -> Bool -> Fay ()
-addEventListener = ffi "%1['addEventListener'](%2,%3,%4)" FayNone
+addEventListener = ffi "%1['addEventListener'](%2,%3,%4)"
 
 -- | Get an element by its ID.
 getElementById :: String -> Fay Element
-getElementById = ffi "document['getElementById'](%1)" FayNone
+getElementById = ffi "document['getElementById'](%1)"
 
 --------------------------------------------------------------------------------
 -- Images
@@ -70,11 +70,11 @@
 
 -- | Make a new image.
 newImage :: Fay Image
-newImage = ffi "new Image()" FayNone
+newImage = ffi "new Image()"
 
 -- | Make a new image.
 setSrc :: Image -> String -> Fay ()
-setSrc = ffi "%1['src'] = %2" FayNone
+setSrc = ffi "%1['src'] = %2"
 
 --------------------------------------------------------------------------------
 -- Canvas
@@ -85,11 +85,11 @@
 
 -- | Get an element by its ID.
 getContext :: Element -> String -> Fay Context
-getContext = ffi "%1['getContext'](%2)" FayNone
+getContext = ffi "%1['getContext'](%2)"
 
 -- | Draw an image onto a canvas rendering context.
 drawImage :: Context -> Image -> Double -> Double -> Fay ()
-drawImage = ffi "%1['drawImage'](%2,%3,%4)" FayNone
+drawImage = ffi "%1['drawImage'](%2,%3,%4)"
 
 -- | Draw an image onto a canvas rendering context.
 --
@@ -101,15 +101,15 @@
 drawImageSpecific :: Context -> Image
                   -> Double -> Double -> Double -> Double -> Double -> Double -> Double -> Double
                   -> Fay ()
-drawImageSpecific = ffi "%1['drawImage'](%2,%3,%4,%5,%6,%7,%8,%9,%10)" FayNone
+drawImageSpecific = ffi "%1['drawImage'](%2,%3,%4,%5,%6,%7,%8,%9,%10)"
 
 -- | Set the fill style.
 setFillStyle :: Context -> String -> Fay ()
-setFillStyle = ffi "%1['fillStyle']=%2" FayNone
+setFillStyle = ffi "%1['fillStyle']=%2"
 
 -- | Set the fill style.
 setFillRect :: Context -> Double -> Double -> Double -> Double -> Fay ()
-setFillRect = ffi "%1['fillRect'](%2,%3,%4,%5)" FayNone
+setFillRect = ffi "%1['fillRect'](%2,%3,%4,%5)"
 
 --------------------------------------------------------------------------------
 -- Ref
@@ -120,35 +120,35 @@
 
 -- | Make a new mutable reference.
 newRef :: Foreign a => a -> Fay (Ref a)
-newRef = ffi "new Fay$$Ref(%1)" FayNone
+newRef = ffi "new Fay$$Ref(%1)"
 
 -- | Replace the value in the mutable reference.
 writeRef :: Foreign a => Ref a -> a -> Fay ()
-writeRef = ffi "Fay$$writeRef(%1,%2)" FayNone
+writeRef = ffi "Fay$$writeRef(%1,%2)"
 
 -- | Get the referred value from the mutable value.
 readRef :: Foreign a => Ref a -> Fay a
-readRef = ffi "Fay$$readRef(%1)" FayNone
+readRef = ffi "Fay$$readRef(%1)"
 
 --------------------------------------------------------------------------------
 -- Misc
 
 -- | Alert using window.alert.
 alert :: Foreign a => a -> Fay ()
-alert = ffi "window['alert'](%1)" FayNone
+alert = ffi "window['alert'](%1)"
 
 -- | Alert using window.alert.
 print :: Double -> Fay ()
-print = ffi "console['log'](%1)" FayNone
+print = ffi "console['log'](%1)"
 
 -- | Alert using window.alert.
 log :: String -> Fay ()
-log = ffi "console['log'](%1)" FayNone
+log = ffi "console['log'](%1)"
 
 -- | Alert using window.alert.
 sin :: Double -> Double
-sin = ffi "window.Math['sin'](%1)" FayNone
+sin = ffi "window.Math['sin'](%1)"
 
 -- | Alert using window.alert.
 setInterval :: Fay () -> Double -> Fay ()
-setInterval = ffi "window['setInterval'](%1,%2)" FayNone
+setInterval = ffi "window['setInterval'](%1,%2)"
diff --git a/examples/console.hs b/examples/console.hs
--- a/examples/console.hs
+++ b/examples/console.hs
@@ -8,5 +8,5 @@
 main = print "Hello, World!"
 
 -- | Print using console.log.
-print :: Foreign a => a -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print :: String -> Fay ()
+print = ffi "console.log(%1)"
diff --git a/examples/data.hs b/examples/data.hs
--- a/examples/data.hs
+++ b/examples/data.hs
@@ -18,4 +18,4 @@
 main = print (show (Foo 123 "abc" Bar))
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/examples/dom.hs b/examples/dom.hs
--- a/examples/dom.hs
+++ b/examples/dom.hs
@@ -12,16 +12,16 @@
 printBody :: Fay ()
 printBody = do
   result <- documentGetElements "body"
-  print result
+  print (show result)
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
 
 data Element
 instance Foreign Element
 
 documentGetElements :: String -> Fay [Element]
-documentGetElements = ffi "document.getElementsByTagName(%1)" FayArray
+documentGetElements = ffi "document.getElementsByTagName(%1)"
 
 addEventListener :: String -> Fay () -> Bool -> Fay ()
-addEventListener = ffi "window['addEventListener'](%1,%2,%3)" FayNone
+addEventListener = ffi "window['addEventListener'](%1,%2,%3)"
diff --git a/examples/ref.hs b/examples/ref.hs
--- a/examples/ref.hs
+++ b/examples/ref.hs
@@ -20,13 +20,13 @@
 instance Foreign a => Foreign (Ref a)
 
 newRef :: Foreign a => a -> Fay (Ref a)
-newRef = ffi "new Fay$$Ref(%1)" FayNone
+newRef = ffi "new Fay$$Ref(%1)"
 
 writeRef :: Foreign a => Ref a -> a -> Fay ()
-writeRef = ffi "Fay$$writeRef(%1,%2)" FayNone
+writeRef = ffi "Fay$$writeRef(%1,%2)"
 
 readRef :: Foreign a => Ref a -> Fay a
-readRef = ffi "Fay$$readRef(%1)" FayNone
+readRef = ffi "Fay$$readRef(%1)"
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/examples/tailrecursive.hs b/examples/tailrecursive.hs
--- a/examples/tailrecursive.hs
+++ b/examples/tailrecursive.hs
@@ -28,10 +28,10 @@
 sum n acc = sum (n - 1) (acc + n)
 
 getSeconds :: Fay Double
-getSeconds = foreignFay "new Date" FayNone
+getSeconds = ffi "new Date()"
 
 printD :: Double -> Fay ()
-printD = foreignFay "console.log" FayNone
+printD = ffi "console.log(%1)"
 
 printS :: String -> Fay ()
-printS = foreignFay "console.log" FayNone
+printS = ffi "console.log(%1)"
diff --git a/fay.cabal b/fay.cabal
--- a/fay.cabal
+++ b/fay.cabal
@@ -1,5 +1,5 @@
 name:                fay
-version:             0.4.0.4
+version:             0.5.0.0
 synopsis:            A compiler for Fay, a Haskell subset that compiles to JavaScript.
 description:         Fay is a proper subset of Haskell which can be compiled (type-checked)
                      with GHC, and compiled to JavaScript. It is lazy, pure, with a Fay monad,
@@ -22,7 +22,7 @@
                      .
                      /Release Notes/
                      .
-                     * Added help to the fay compiler executable.
+                     * MAJOR FFI RESTRUCTURING. Please see commit d6c346c320245762432928bc83aa8ca98a426138.
                      .
                      See full history at: <https://github.com/chrisdone/fay/commits>
 homepage:            http://fay-lang.org/
@@ -48,7 +48,8 @@
                      tests/23 tests/23.hs tests/24 tests/24.hs tests/25.hs tests/26 tests/26.hs
                      tests/2.hs tests/3 tests/3.hs tests/4 tests/4.hs tests/5 tests/5.hs tests/6
                      tests/6.hs tests/7 tests/7.hs tests/8 tests/8.hs tests/9 tests/9.hs tests/27
-                     tests/27.hs tests/28 tests/28.hs
+                     tests/27.hs tests/28 tests/28.hs tests/30.hs tests/29 tests/30 tests/29.hs
+                     tests/31.hs tests/31
                      -- Documentation files
                      docs/beautify.js docs/highlight.pack.js docs/home.css docs/home.js docs/jquery.js
                      docs/analytics.js
@@ -64,8 +65,6 @@
                      docs/snippets/patterns.hs
                      docs/snippets/tail.hs
                      docs/home.hs
-                     -- Misc
-                     CHANGELOG
 
 library
   hs-source-dirs:    src
diff --git a/hs/stdlib.hs b/hs/stdlib.hs
--- a/hs/stdlib.hs
+++ b/hs/stdlib.hs
@@ -1,19 +1,9 @@
-data ArgType
-  = DateType
-  | FunctionType
-  | JsType
-  | StringType
-  | DoubleType
-  | ListType
-  | BoolType
-  | UnknownType
-
 data Maybe a
   = Just a
   | Nothing
 
 show :: (Foreign a,Show a) => a -> String
-show = ffi "Fay$$encodeShow(%1)" FayString
+show = ffi "Fay$$encodeShow(%1)"
 
 -- There is only Double in JS.
 fromInteger x = x
diff --git a/js/runtime.js b/js/runtime.js
--- a/js/runtime.js
+++ b/js/runtime.js
@@ -2,15 +2,15 @@
 var False = false;
 
 /*******************************************************************************
-* Thunks.
-*/
+ * Thunks.
+ */
 
 // Force a thunk (if it is a thunk) until WHNF.
 function _(thunkish,nocache){
-  while (thunkish instanceof $) {
-    thunkish = thunkish.force(nocache);
-  }
-  return thunkish;
+    while (thunkish instanceof $) {
+        thunkish = thunkish.force(nocache);
+    }
+    return thunkish;
 }
 
 // Apply a function to arguments (see method2 in Fay.hs).
@@ -24,339 +24,410 @@
 
 // Thunk object.
 function $(value){
-  this.forced = false;
-  this.value = value;
+    this.forced = false;
+    this.value = value;
 }
 
 // Force the thunk.
 $.prototype.force = function(nocache){
-  return nocache
-    ? this.value()
-    : this.forced
-    ? this.value
-    : (this.forced = true, this.value = this.value());
+    return nocache
+        ? this.value()
+        : this.forced
+        ? this.value
+        : (this.forced = true, this.value = this.value());
 };
 
 /*******************************************************************************
-* Constructors.
-*/
+ * Constructors.
+ */
 
 // A constructor.
 function Fay$$Constructor(){
-  this.name = arguments[0];
-  this.fields = Array.prototype.slice.call(arguments,1);
+    this.name = arguments[0];
+    this.fields = Array.prototype.slice.call(arguments,1);
 }
 
 // Eval in the context of the Haskell bindings.
 function Fay$$eval(str){
-  return eval(str);
+    return eval(str);
 }
 
 /*******************************************************************************
-* Monad.
-*/
+ * Monad.
+ */
 
 function Fay$$Monad(value){
-  this.value = value;
+    this.value = value;
 }
 
 // >>
 function Fay$$then(a){
-  return function(b){
-    return new $(function(){
-      _(a,true);
-      return b;
-    });
-  };
+    return function(b){
+        return new $(function(){
+            _(a,true);
+            return b;
+        });
+    };
 }
 
 // >>=
 function Fay$$bind(m){
-  return function(f){
-    return new $(function(){
-      var monad = _(m,true);
-      return f(monad.value);
-    });
-  };
+    return function(f){
+        return new $(function(){
+            var monad = _(m,true);
+            return f(monad.value);
+        });
+    };
 }
 
 var Fay$$unit = null;
 
 // return
 function Fay$$return(a){
-  return new Fay$$Monad(a);
+    return new Fay$$Monad(a);
 }
 
 /*******************************************************************************
-* FFI.
-*/
+ * FFI.
+ */
 
 // Serialize a Fay object to JS.
-function Fay$$serialize(type,obj){
-  type = _(type);
-  if(type) type = type[0].name;
-  if(type == "JsType"){
-    return function(){
-      return _(obj,true).value;
-    };
-  } else {
-    obj = _(obj);
-    if(type == "StringType" ||
-       (obj instanceof Fay$$Cons && typeof obj.car == 'string')){
-      var str = "";
-      while(obj instanceof Fay$$Cons) {
-        str += obj.car;
-        obj = _(obj.cdr);
-      }
-      return str;
-    } else if(type == "FunctionType" || typeof obj == 'function'){
-      return function(){
-        var out = obj;
-        for (var len = arguments.length, i = 0; i < len; i++){
-          if(typeof out != 'function') {
-            throw "Wrong number of arguments for callback: " + arguments.toString();
-          }
-          out = out(arguments[i]);
+function Fay$$serialize(type,fayObj){
+    var base = type[0];
+    var args = type[1];
+    var jsObj;
+    switch(base){
+    case "action": {
+        // A nullary monadic action. Should become a nullary JS function.
+        // Fay () -> function(){ return ... }
+        jsObj = function(){
+            return Fay$$serialize(args[0],_(fayObj,true).value);
+        };
+        break;
+    }
+    case "function": {
+        // A proper function.
+        jsObj = function(){
+            var return_type = args[args.length-1];
+            var len = args.length;
+            // If some arguments.
+            if (len > 1) {
+                // Apply to all the arguments.
+                fayObj = _(fayObj,true);
+                for (var i = 0, len = len; i < len - 1; i++) {
+                    // Unserialize the JS values to Fay for the Fay callback.
+                    fayObj = _(fayObj(Fay$$unserialize(args[i],arguments[i])),true);
+                }
+                // Finally, serialize the Fay return value back to JS.
+                var return_base = return_type[0];
+                var return_args = return_type[1];
+                // If it's a monadic return value, get the value instead.
+                if(return_base == "action") {
+                    return Fay$$serialize(return_args[0],fayObj.value);
+                }
+                // Otherwise just serialize the value direct.
+                else {
+                    return Fay$$serialize(return_type,fayObj);
+                }
+            } else {
+                throw new Error("Nullary function?");
+            }
+        };
+        break;
+    }
+    case "string": {
+        // Serialize Fay string to JavaScript string.
+        var str = "";
+        fayObj = _(fayObj);
+        while(fayObj instanceof Fay$$Cons) {
+            str += fayObj.car;
+            fayObj = _(fayObj.cdr);
         }
-        return _(out,true);
-      };
-    } else if(type == "ListType" || (obj instanceof Fay$$Cons)){
-      var arr = [];
-      while(obj instanceof Fay$$Cons) {
-        arr.push(Fay$$serialize(null,obj.car));
-        obj = _(obj.cdr);
-      }
-      return arr;
-    } // else if(type == "BoolType || obj == _(True) || obj == _(False)) {
-    //   return obj == _(True);
-    // }
-    else {
-      return obj;
+        jsObj = str;
+        break;
     }
-  }
+    case "list": {
+        // Serialize Fay list to JavaScript array.
+        var arr = [];
+        fayObj = _(fayObj);
+        while(fayObj instanceof Fay$$Cons) {
+            arr.push(Fay$$serialize(args[0],fayObj.car));
+            fayObj = _(fayObj.cdr);
+        }
+        jsObj = arr;
+        break;
+    }
+    case "double": {
+        // Serialize double, just force the argument. Doubles are unboxed.
+        jsObj = _(fayObj);
+        break;
+    }
+    case "unknown": {
+        // Just force unknown values to WHNF.
+        jsObj = _(fayObj);
+        break;
+    }
+    case "bool": {
+        // Bools are unboxed.
+        jsObj = fayObj;
+        break;
+    }
+    default: throw new Error("Unhandled serialize type: " + base);
+    }
+    return jsObj;
 }
 
+// Unserialize an object from JS to Fay.
+function Fay$$unserialize(type,jsObj){
+    var base = type[0];
+    var args = type[1];
+    var fayObj;
+    switch(base){
+    case "action": {
+        // Unserialize a "monadic" JavaScript return value into a monadic value.
+        fayObj = Fay$$return(Fay$$unserialize(args[0],jsObj));
+        break;
+    }
+    case "string": {
+        // Unserialize a JS string into Fay list (String).
+        fayObj = Fay$$list(jsObj);
+        break;
+    }
+    case "list": {
+        // Unserialize a JS array into a Fay list ([a]).
+        var serializedList = [];
+        for (var i = 0, len = jsObj.length; i < len; i++) {
+            // Unserialize each JS value into a Fay value, too.
+            serializedList.push(Fay$$unserialize(args[0],jsObj[i]));
+        }
+        // Pop it all in a Fay list.
+        fayObj = Fay$$list(serializedList);
+        break;
+    }
+    case "double": {
+        // Doubles are unboxed, so there's nothing to do.
+        fayObj = jsObj;
+        break;
+    }
+    case "unknown": {
+        // Any unknown values can be left as-is.
+        fayObj = jsObj;
+        break;
+    }
+    default: throw new Error("Unhandled unserialize type: " + base);
+    }
+    return fayObj;
+}
+
 // Encode a value to a Show representation
 function Fay$$encodeShow(x){
-  if (x instanceof $) x = _(x);
-  if (x instanceof Array) {
-    if (x.length == 0) {
-      return "[]";
-    } else {
-      if (x[0] instanceof Fay$$Constructor) {
-        if(x[0].fields.length > 0) {
-          var args = x.slice(1);
-          var fieldNames = x[0].fields;
-          return "(" + x[0].name + " { " + args.map(function(x,i){
-            return fieldNames[i] + ' = ' + Fay$$encodeShow(x);
-          }).join(", ") + " })";
+    if (x instanceof $) x = _(x);
+    if (x instanceof Array) {
+        if (x.length == 0) {
+            return "[]";
         } else {
-          var args = x.slice(1);
-          return "(" + [x[0].name].concat(args.map(Fay$$encodeShow)).join(" ") + ")";
+            if (x[0] instanceof Fay$$Constructor) {
+                if(x[0].fields.length > 0) {
+                    var args = x.slice(1);
+                    var fieldNames = x[0].fields;
+                    return "(" + x[0].name + " { " + args.map(function(x,i){
+                        return fieldNames[i] + ' = ' + Fay$$encodeShow(x);
+                    }).join(", ") + " })";
+                } else {
+                    var args = x.slice(1);
+                    return "(" + [x[0].name].concat(args.map(Fay$$encodeShow)).join(" ") + ")";
+                }
+            } else {
+                return "[" + x.map(Fay$$encodeShow).join(",") + "]";
+            }
         }
-      } else {
-        return "[" + x.map(Fay$$encodeShow).join(",") + "]";
-      }
+    } else if (typeof x == 'string') {
+        return JSON.stringify(x);
+    } else if(x instanceof Fay$$Cons) {
+        return Fay$$encodeShow(Fay$$serialize(["list",[["unknown"]]],x));
+    } else if(x == null) {
+        return '[]';
+    } else {
+        return x.toString();
     }
-  } else if (typeof x == 'string') {
-    return JSON.stringify(x);
-  } else if(x instanceof Fay$$Cons) {
-    return Fay$$encodeShow(Fay$$serialize(ListType,x));
-  } else if(x == null) {
-    return '[]';
-  } else {
-    return x.toString();
-  }
 }
 
-// Unserialize an object from JS to Fay.
-function Fay$$unserialize(typ,obj){
-  if(typ == 'string' || typ == 'array' || typ == 'list')
-    return Fay$$list(obj);
-  else if(typ == 'bool')
-    return obj? True : False;
-  else if(typ == 'data') {
-    alert('Time to unserialize a data record!');
-  }
-  else return obj;
-}
-
 /*******************************************************************************
-* Lists.
-*/
+ * Lists.
+ */
 
 // Cons object.
 function Fay$$Cons(car,cdr){
-  this.car = car;
-  this.cdr = cdr;
+    this.car = car;
+    this.cdr = cdr;
 }
 
 // Make a list.
 function Fay$$list(xs){
-  var out = null;
-  for(var i=xs.length-1; i>=0;i--)
-    out = new Fay$$Cons(xs[i],out);
-  return out;
+    var out = null;
+    for(var i=xs.length-1; i>=0;i--)
+        out = new Fay$$Cons(xs[i],out);
+    return out;
 }
 
 // Built-in list cons.
 function Fay$$cons(x){
-  return function(y){
-    return new Fay$$Cons(x,y);
-  };
+    return function(y){
+        return new Fay$$Cons(x,y);
+    };
 }
 
 // List index.
 function Fay$$index(index){
-  return function(list){
-    for(var i = 0; i < index; i++) {
-      list = _(list).cdr;
-    }
-    return list.car;
-  };
+    return function(list){
+        for(var i = 0; i < index; i++) {
+            list = _(list).cdr;
+        }
+        return list.car;
+    };
 }
 
 /*******************************************************************************
-* Numbers.
-*/
+ * Numbers.
+ */
 
 // Built-in *.
 function Fay$$mult(x){
-  return function(y){
-    return _(x) * _(y);
-  };
+    return function(y){
+        return _(x) * _(y);
+    };
 }
 
 // Built-in +.
 function Fay$$add(x){
-  return function(y){
-    return _(x) + _(y);
-  };
+    return function(y){
+        return _(x) + _(y);
+    };
 }
 
 // Built-in -.
 function Fay$$sub(x){
-  return function(y){
-    return _(x) - _(y);
-  };
+    return function(y){
+        return _(x) - _(y);
+    };
 }
 
 // Built-in /.
 function Fay$$div(x){
-  return function(y){
-    return _(x) / _(y);
-  };
+    return function(y){
+        return _(x) / _(y);
+    };
 }
 
 /*******************************************************************************
-* Booleans.
-*/
+ * Booleans.
+ */
 
 // Are two values equal?
 function Fay$$equal(lit1,lit2){
-  // Simple case
-  lit1 = _(lit1);
-  lit2 = _(lit2);
-  if(lit1 === lit2) {
-    return true;
-  }
-  // General case
-  if(lit1 instanceof Array) {
-    if(lit1.length!=lit2.length) return false;
-    for(var len = lit1.length, i = 0; i < len; i++) {
-      if(!Fay$$equal(lit1[i],lit2[i]))
-        return false;
+    // Simple case
+    lit1 = _(lit1);
+    lit2 = _(lit2);
+    if(lit1 === lit2) {
+        return true;
     }
-    return true;
-  } else if (lit1 instanceof Fay$$Cons) {
-    while(lit1 instanceof Fay$$Cons && lit2 instanceof Fay$$Cons && Fay$$equal(lit1.car,lit2.car))
-      lit1 = lit1.cdr, lit2 = lit2.cdr;
-    return (lit1 === null && lit2 === null);
-  } else return false;
+    // General case
+    if(lit1 instanceof Array) {
+        if(lit1.length!=lit2.length) return false;
+        for(var len = lit1.length, i = 0; i < len; i++) {
+            if(!Fay$$equal(lit1[i],lit2[i]))
+                return false;
+        }
+        return true;
+    } else if (lit1 instanceof Fay$$Cons) {
+        while(lit1 instanceof Fay$$Cons && lit2 instanceof Fay$$Cons && Fay$$equal(lit1.car,lit2.car))
+            lit1 = lit1.cdr, lit2 = lit2.cdr;
+        return (lit1 === null && lit2 === null);
+    } else return false;
 }
 
 // Built-in ==.
 function Fay$$eq(x){
-  return function(y){
-    return Fay$$equal(x,y);
-  };
+    return function(y){
+        return Fay$$equal(x,y);
+    };
 }
 
 // Built-in /=.
 function Fay$$neq(x){
-  return function(y){
-    return !(Fay$$equal(x,y));
-  };
+    return function(y){
+        return !(Fay$$equal(x,y));
+    };
 }
 
 // Built-in >.
 function Fay$$gt(x){
-  return function(y){
-    return _(x) > _(y);
-  };
+    return function(y){
+        return _(x) > _(y);
+    };
 }
 
 // Built-in <.
 function Fay$$lt(x){
-  return function(y){
-    return _(x) < _(y);
-  };
+    return function(y){
+        return _(x) < _(y);
+    };
 }
 
 // Built-in >=.
 function Fay$$gte(x){
-  return function(y){
-    return _(x) >= _(y);
-  };
+    return function(y){
+        return _(x) >= _(y);
+    };
 }
 
 // Built-in <=.
 function Fay$$lte(x){
-  return function(y){
-    return _(x) <= _(y);
-  };
+    return function(y){
+        return _(x) <= _(y);
+    };
 }
 
 // Built-in &&.
 function Fay$$and(x){
-  return function(y){
-    return _(x) && _(y);
-  };
+    return function(y){
+        return _(x) && _(y);
+    };
 }
 
 // Built-in ||.
 function Fay$$or(x){
-  return function(y){
-    return _(x) || _(y);
-  };
+    return function(y){
+        return _(x) || _(y);
+    };
 }
 
 /*******************************************************************************
-* Mutable references.
-*/
+ * Mutable references.
+ */
 
 // Make a new mutable reference.
 function Fay$$Ref(x){
-  this.value = x;
+    this.value = x;
 }
 
 // Write to the ref.
 function Fay$$writeRef(ref,x){
-  ref.value = x;
+    ref.value = x;
 }
 
 // Get the value from the ref.
 function Fay$$readRef(ref,x){
-  return ref.value;
+    return ref.value;
 }
 
 /*******************************************************************************
-* Dates.
-*/
+ * Dates.
+ */
 function Fay$$date(str){
-  return window.Date.parse(str);
+    return window.Date.parse(str);
 }
 
 /*******************************************************************************
-* Application code.
-*/
+ * Application code.
+ */
diff --git a/src/Language/Fay.hs b/src/Language/Fay.hs
--- a/src/Language/Fay.hs
+++ b/src/Language/Fay.hs
@@ -159,26 +159,22 @@
   case pat of
     PatBind _ (PVar ident) Nothing (UnGuardedRhs rhs) (BDecls []) ->
       case ffiExp rhs of
-        Just (formatstr,typ) -> case sig of
-          Just sig -> compileFFI ident formatstr typ sig
+        Just formatstr -> case sig of
+          Just sig -> compileFFI ident formatstr sig
           Nothing  -> throwError (FfiNeedsTypeSig pat)
         _ -> compileNormalPatBind toplevel ident rhs
     _ -> throwError (UnsupportedDeclaration pat)
 
-  where ffiExp (App (App (Var (UnQual (Ident "ffi")))
-                         (Lit (String formatstr)))
-                    (Con (UnQual (Ident (reads -> [(typ,"")])))))
-          = Just (formatstr,typ)
+  where ffiExp (App (Var (UnQual (Ident "ffi"))) (Lit (String formatstr))) = Just formatstr
         ffiExp _ = Nothing
 
 -- | Compile an FFI call.
-compileFFI :: Name             -- ^ Name of the to-be binding.
-           -> String           -- ^ The format string.
-           -> FayReturnType    -- ^ The return type.
-           -> Type             -- ^ Type signature.
+compileFFI :: Name   -- ^ Name of the to-be binding.
+           -> String -- ^ The format string.
+           -> Type   -- ^ Type signature.
            -> Compile [JsStmt]
-compileFFI name formatstr returnType sig = do
-  inner <- formatFFI formatstr (zip params funcArgTypes)
+compileFFI name formatstr sig = do
+  inner <- formatFFI formatstr (zip params funcFundamentalTypes)
   case JS.parse (printJS (wrapReturn inner)) (prettyPrint name) of
     Left err -> throwError (FfiFormatInvalidJavaScript inner err)
     Right{}  -> fmap return (bindToplevel True (UnQual name) (body inner))
@@ -187,19 +183,18 @@
         wrapParam name inner = JsFun [name] [] (Just inner)
         params = zipWith const uniqueNames [1..typeArity sig]
         wrapReturn inner = thunk $
-          case lastMay funcArgTypes of
-            -- Fay action:
-            Just JsType -> monad (unserialize returnType (JsRawExp inner))
+          case lastMay funcFundamentalTypes of
             -- Returns a “pure” value;
             Just{} -> unserialize returnType (JsRawExp inner)
             -- Base case:
             Nothing -> JsRawExp inner
-        funcArgTypes = functionTypeArgs sig
+        funcFundamentalTypes = functionTypeArgs sig
+        returnType = last funcFundamentalTypes
 
 -- | Format the FFI format string with the given arguments.
-formatFFI :: String              -- ^ The format string.
-          -> [(JsParam,ArgType)] -- ^ Arguments.
-          -> Compile String      -- ^ The JS code.
+formatFFI :: String                      -- ^ The format string.
+          -> [(JsParam,FundamentalType)] -- ^ Arguments.
+          -> Compile String              -- ^ The JS code.
 formatFFI formatstr args = go formatstr where
   go ('%':'*':xs) = do
     these <- mapM inject (zipWith const [1..] args)
@@ -227,15 +222,30 @@
         return (printJS (serialize typ (JsName arg)))
 
 -- | Serialize a value to native JS, if possible.
-serialize :: ArgType -> JsExp -> JsExp
+serialize :: FundamentalType -> JsExp -> JsExp
 serialize typ exp =
   case typ of
 --    UnknownType -> force exp
     _ -> JsApp (JsName (hjIdent "serialize"))
-               [JsName (fromString (show typ)),exp]
+               [typeRep typ,exp]
 
+-- | Get a JS-representation of a fundamental type for encoding/decoding.
+typeRep :: FundamentalType -> JsExp
+typeRep typ =
+  case typ of
+    FunctionType xs -> JsList [JsLit $ JsStr "function",JsList (map typeRep xs)]
+    JsType x        -> JsList [JsLit $ JsStr "action",JsList [typeRep x]]
+    ListType x      -> JsList [JsLit $ JsStr "list",JsList [typeRep x]]
+    typ             -> JsList [JsLit $ JsStr nom]
+      where nom = case typ of
+              StringType -> "string"
+              DoubleType -> "double"
+              BoolType   -> "bool"
+              DateType   -> "date"
+              _          -> "unknown"
+
 -- | Get arg types of a function type.
-functionTypeArgs :: Type -> [ArgType]
+functionTypeArgs :: Type -> [FundamentalType]
 functionTypeArgs t =
   case t of
     TyForall _ _ i -> functionTypeArgs i
@@ -244,15 +254,15 @@
     r              -> [argType r]
 
 -- | Convert a Haskell type to an internal FFI representation.
-argType :: Type -> ArgType
+argType :: Type -> FundamentalType
 argType t =
   case t of
-    TyApp (TyCon "Fay") _ -> JsType
+    TyApp (TyCon "Fay") a -> JsType (argType a)
     TyCon "String"        -> StringType
     TyCon "Double"        -> DoubleType
     TyCon "Bool"          -> BoolType
-    TyFun{}               -> FunctionType
-    TyList _              -> ListType
+    TyFun x xs            -> FunctionType (argType x : functionTypeArgs xs)
+    TyList x              -> ListType (argType x)
     TyParen st            -> argType st
     _                     -> UnknownType
 
@@ -392,8 +402,18 @@
 -- | Compile a right-hand-side expression.
 compileRhs :: Rhs -> Compile JsExp
 compileRhs (UnGuardedRhs exp) = compileExp exp
-compileRhs rhs                = throwError (UnsupportedRhs rhs)
+compileRhs (GuardedRhss rhss) = compileGuards rhss
 
+-- | Compile guards
+compileGuards :: [GuardedRhs] -> Compile JsExp
+compileGuards [] = return . JsThrowExp . JsLit . JsStr $ "Non-exhaustive guards"
+compileGuards ((GuardedRhs _ (Qualifier (Var (UnQual (Ident "otherwise"))):_) exp):_) = compileExp exp
+compileGuards ((GuardedRhs _ (Qualifier guard:_) exp):rest) =
+  JsTernaryIf <$> fmap force (compileExp guard)
+              <*> compileExp exp
+              <*> compileGuards rest
+compileGuards rhss = throwError . UnsupportedRhs . GuardedRhss $ rhss
+
 -- | Compile a pattern match binding.
 compileFunMatch :: Bool -> Match -> Compile [JsStmt]
 compileFunMatch toplevel match =
@@ -496,8 +516,10 @@
 compileList :: [Exp] -> Compile JsExp
 compileList xs = do
   exps <- mapM compileExp xs
-  return (JsApp (JsName (hjIdent "list")) [JsList exps])
+  return (makeList exps)
 
+makeList exps = (JsApp (JsName (hjIdent "list")) [JsList exps])
+
 -- | Compile an if.
 compileIf :: Exp -> Exp -> Exp -> Compile JsExp
 compileIf cond conseq alt =
@@ -773,18 +795,10 @@
 stmtsThunk :: [JsStmt] -> JsExp
 stmtsThunk stmts = JsNew ":thunk" [JsFun [] stmts Nothing]
 
-unserialize :: FayReturnType -> JsExp -> JsExp
+unserialize :: FundamentalType -> JsExp -> JsExp
 unserialize typ exp =
   JsApp (JsName (hjIdent "unserialize"))
-        [JsLit (JsStr (showReturnType typ)),exp]
-
-  where showReturnType typ =
-          case typ of
-            FayArray -> "array"
-            FayList -> "list"
-            FayString -> "string"
-            FayBool -> "bool"
-            FayNone -> ""
+        [typeRep typ,exp]
 
 -- | Force an expression in a thunk.
 force :: JsExp -> JsExp
diff --git a/src/Language/Fay/Compiler.hs b/src/Language/Fay/Compiler.hs
--- a/src/Language/Fay/Compiler.hs
+++ b/src/Language/Fay/Compiler.hs
@@ -56,6 +56,7 @@
                                               ,"this.$list       = Fay$$list;"
                                               ,"this.$encodeShow = Fay$$encodeShow;"
                                               ,"this.$eval       = Fay$$eval;"
+                                              ,"this.$serialize  = Fay$$serialize;"
                                               ]
                                  else ""
                              ,"};"
diff --git a/src/Language/Fay/FFI.hs b/src/Language/Fay/FFI.hs
--- a/src/Language/Fay/FFI.hs
+++ b/src/Language/Fay/FFI.hs
@@ -4,7 +4,7 @@
 
 module Language.Fay.FFI where
 
-import           Language.Fay.Types (Fay, FayReturnType(..))
+import           Language.Fay.Types (Fay)
 import           Prelude            (Bool, Char, Double, String, error)
 
 data JsPtr a
@@ -40,6 +40,5 @@
 ffi
   :: Foreign a
   => String        -- ^ The foreign value.
-  -> FayReturnType -- ^ JS return type (if any).
   -> a             -- ^ Bottom.
 ffi = error "Language.Fay.FFI.foreignFay: Used foreign function not in a JS engine context."
diff --git a/src/Language/Fay/Prelude.hs b/src/Language/Fay/Prelude.hs
--- a/src/Language/Fay/Prelude.hs
+++ b/src/Language/Fay/Prelude.hs
@@ -2,7 +2,6 @@
 
 module Language.Fay.Prelude
   (Fay
-  ,FayReturnType(..)
   ,Char
   ,String
   ,Integer
@@ -34,7 +33,7 @@
   where
 
 import           Language.Fay.Stdlib
-import           Language.Fay.Types  (Fay, FayReturnType(..))
+import           Language.Fay.Types  (Fay)
 
 import           GHC.Real            (Ratio)
 import           Prelude             (Bool(..), Char, Double, Integer, Maybe(..), Ord, Read(..),
diff --git a/src/Language/Fay/Types.hs b/src/Language/Fay/Types.hs
--- a/src/Language/Fay/Types.hs
+++ b/src/Language/Fay/Types.hs
@@ -18,8 +18,7 @@
   ,Fay
   ,CompileConfig(..)
   ,CompileState(..)
-  ,FayReturnType(..)
-  ,ArgType(..))
+  ,FundamentalType(..))
   where
 
 import           Control.Applicative
@@ -158,13 +157,21 @@
   | JsBool Bool
   deriving (Show,Eq)
 
-data FayReturnType = FayArray | FayList | FayString | FayBool | FayNone
-  deriving (Read,Show,Eq)
-
 -- | These are the data types that are serializable directly to native
 -- JS data types. Strings, floating points and arrays. The others are:
 -- actiosn in the JS monad, which are thunks that shouldn't be forced
 -- when serialized but wrapped up as JS zero-arg functions, and
 -- unknown types can't be converted but should at least be forced.
-data ArgType = FunctionType | JsType | StringType | DoubleType | ListType | BoolType | UnknownType
-  deriving (Show,Eq)
+data FundamentalType
+   -- Recursive types.
+ = FunctionType [FundamentalType]
+ | JsType FundamentalType
+ | ListType FundamentalType
+ -- Simple types.
+ | DateType
+ | StringType
+ | DoubleType
+ | BoolType
+ -- | Unknown.
+ | UnknownType
+   deriving (Show,Eq)
diff --git a/src/Main.hs b/src/Main.hs
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -37,5 +37,8 @@
   ,"  fay [OPTIONS] <hs-input-file> ... "
   ,""
   ,"OPTIONS"
-  ,"  -autorun    automatically call main in generated JavaScript"
+  ,"  -autorun       automatically call main in generated JavaScript"
+  ,"  -inline-force  inline forcing, adds some speed for numbers, blows up code a bit"
+  ,"  -flatten-apps  flatten function application, can be more readable,"
+  ,"                 no noticeable speed difference"
   ]
diff --git a/tests/10.hs b/tests/10.hs
--- a/tests/10.hs
+++ b/tests/10.hs
@@ -9,4 +9,4 @@
 append []     ys = ys
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/11.hs b/tests/11.hs
--- a/tests/11.hs
+++ b/tests/11.hs
@@ -1,4 +1,4 @@
-main = print (show (take 5 (let ns = 1 : map (\x -> x + 1) ns in ns)))
+main = print (showList (take 5 (let ns = 1 : map (\x -> x + 1) ns in ns)))
 
 take 0 _      = []
 take n (x:xs) = x : take (n - 1) xs
@@ -7,4 +7,7 @@
 map f (x:xs) = f x : map f xs
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
+
+showList :: [Double] -> String
+showList = ffi "JSON.stringify(%1)"
diff --git a/tests/12.hs b/tests/12.hs
--- a/tests/12.hs
+++ b/tests/12.hs
@@ -1,4 +1,4 @@
-main = print (show (take 5 (let ns = 1 : map (foo 123) ns in ns)))
+main = print (showList (take 5 (let ns = 1 : map (foo 123) ns in ns)))
 
 foo x y = x * y / 2
 
@@ -9,7 +9,7 @@
 map f (x:xs) = f x : map f xs
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
 
-show :: String -> String
-show = ffi "JSON.stringify(%1)" FayString
+showList :: [Double] -> String
+showList = ffi "JSON.stringify(%1)"
diff --git a/tests/13.hs b/tests/13.hs
--- a/tests/13.hs
+++ b/tests/13.hs
@@ -3,4 +3,4 @@
                False -> "Ney!")
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/14.hs b/tests/14.hs
--- a/tests/14.hs
+++ b/tests/14.hs
@@ -3,4 +3,4 @@
                False -> "Ney!")
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/15.hs b/tests/15.hs
--- a/tests/15.hs
+++ b/tests/15.hs
@@ -3,4 +3,4 @@
                _    -> "Ney!")
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/16.hs b/tests/16.hs
--- a/tests/16.hs
+++ b/tests/16.hs
@@ -4,4 +4,4 @@
                 Person "Chris" "Done" 13 -> "Hello!")
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/17.hs b/tests/17.hs
--- a/tests/17.hs
+++ b/tests/17.hs
@@ -5,4 +5,4 @@
                 _ -> "World!")
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/18.hs b/tests/18.hs
--- a/tests/18.hs
+++ b/tests/18.hs
@@ -7,4 +7,4 @@
                 _ -> "World!")
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/19.hs b/tests/19.hs
--- a/tests/19.hs
+++ b/tests/19.hs
@@ -8,4 +8,4 @@
 foo _ = "World!"
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/20.hs b/tests/20.hs
--- a/tests/20.hs
+++ b/tests/20.hs
@@ -1,4 +1,4 @@
 main = print "Hello," >> print "World!"
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/21.hs b/tests/21.hs
--- a/tests/21.hs
+++ b/tests/21.hs
@@ -1,4 +1,4 @@
 main = do print "Hello,"; print "World!"
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/22.hs b/tests/22.hs
--- a/tests/22.hs
+++ b/tests/22.hs
@@ -3,4 +3,4 @@
   print x
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/23.hs b/tests/23.hs
--- a/tests/23.hs
+++ b/tests/23.hs
@@ -3,4 +3,4 @@
   print "OK."
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/24.hs b/tests/24.hs
--- a/tests/24.hs
+++ b/tests/24.hs
@@ -5,4 +5,4 @@
   _           -> "Broken.")
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/25.hs b/tests/25.hs
--- a/tests/25.hs
+++ b/tests/25.hs
@@ -1,4 +1,4 @@
 main = print ((\a 'a' -> "OK.") 0 'b')
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/26.hs b/tests/26.hs
--- a/tests/26.hs
+++ b/tests/26.hs
@@ -1,4 +1,4 @@
 main = print (5 * 3 / 2)
 
 print :: Double -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/27.hs b/tests/27.hs
--- a/tests/27.hs
+++ b/tests/27.hs
@@ -14,7 +14,7 @@
 sum n acc = sum (n - 1) (acc + n)
 
 getSeconds :: Fay Double
-getSeconds = foreignFay "new Date" FayNone
+getSeconds = foreignFay "new Date"
 
 print :: Double -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/28.hs b/tests/28.hs
--- a/tests/28.hs
+++ b/tests/28.hs
@@ -5,7 +5,7 @@
 import           Language.Fay.Prelude
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
 
 main :: Fay ()
 main = print $ show $ fromInteger 5
diff --git a/tests/29 b/tests/29
new file mode 100644
--- /dev/null
+++ b/tests/29
@@ -0,0 +1,3 @@
+[[1,2,3],[1,2,3]]
+[[1,2,3],1,[2,3]]
+[[1,2,3],1,[2,3]]
diff --git a/tests/29.hs b/tests/29.hs
new file mode 100644
--- /dev/null
+++ b/tests/29.hs
@@ -0,0 +1,28 @@
+{-# LANGUAGE NoImplicitPrelude #-}
+module Test where
+
+-- | As pattern matches
+
+import Language.Fay.Prelude
+import Language.Fay.FFI
+
+matchSame :: [a] -> ([a],[a])
+matchSame x@y = (x,y)
+
+matchSplit :: [a] -> ([a],a,[a])
+matchSplit x@(y:z) = (x,y,z)
+
+matchNested :: (a, [b]) -> ([b],b,[b])
+matchNested (a,b@(x:xs)) = (b,x,xs)
+
+print :: String -> Fay ()
+print = ffi "console.log(%1)"
+
+main :: Fay ()
+main = do
+  print $ show $ matchSame [1,2,3]
+  print $ show $ matchSplit [1,2,3]
+  print $ show $ matchNested (1, [1,2,3])
+
+show :: Foreign a => a -> String
+show = ffi "JSON.stringify(%1)"
diff --git a/tests/3.hs b/tests/3.hs
--- a/tests/3.hs
+++ b/tests/3.hs
@@ -1,4 +1,4 @@
 main = print 1
 
 print :: Double -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/30 b/tests/30
new file mode 100644
--- /dev/null
+++ b/tests/30
@@ -0,0 +1,3 @@
+[true,false]
+[2,1,0]
+[true,false]
diff --git a/tests/30.hs b/tests/30.hs
new file mode 100644
--- /dev/null
+++ b/tests/30.hs
@@ -0,0 +1,30 @@
+{-# LANGUAGE NoImplicitPrelude #-}
+module Test where
+
+-- | As pattern matches
+
+import Language.Fay.Prelude
+import Language.Fay.FFI
+
+isPositive :: Double -> Bool
+isPositive x | x > 0 = True
+             | x <= 0 = False
+
+threeConds x | x > 1 = 2
+             | x == 1 = 1
+             | x < 1 = 0
+
+withOtherwise x | x > 1 = True
+                | otherwise = False
+
+-- Not called, throws "non-exhaustive guard"
+nonExhaustive x | x > 1 = True
+
+print :: String -> Fay ()
+print = ffi "console.log(%1)"
+
+main :: Fay ()
+main = do
+  print $ show $ (isPositive 1, isPositive 0)
+  print $ show $ (threeConds 3, threeConds 1, threeConds 0)
+  print $ show $ (withOtherwise 2, withOtherwise 0)
diff --git a/tests/31 b/tests/31
new file mode 100644
--- /dev/null
+++ b/tests/31
@@ -0,0 +1,1 @@
+Hai!
diff --git a/tests/31.hs b/tests/31.hs
new file mode 100644
--- /dev/null
+++ b/tests/31.hs
@@ -0,0 +1,32 @@
+-- | Mutable references.
+
+{-# LANGUAGE EmptyDataDecls    #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+
+module Ref where
+
+import           Language.Fay.FFI
+import           Language.Fay.Prelude
+
+main :: Fay ()
+main = do
+  ref <- newRef "Hello, World!"
+  x <- readRef ref
+  writeRef ref "Hai!"
+  readRef ref >>= print
+
+data Ref a
+instance Show (Ref a)
+instance Foreign a => Foreign (Ref a)
+
+newRef :: Foreign a => a -> Fay (Ref a)
+newRef = ffi "new Fay$$Ref(%1)"
+
+writeRef :: Foreign a => Ref a -> a -> Fay ()
+writeRef = ffi "Fay$$writeRef(%1,%2)"
+
+readRef :: Foreign a => Ref a -> Fay a
+readRef = ffi "Fay$$readRef(%1)"
+
+print :: String -> Fay ()
+print = ffi "console.log(%1)"
diff --git a/tests/4.hs b/tests/4.hs
--- a/tests/4.hs
+++ b/tests/4.hs
@@ -1,4 +1,4 @@
 main = print "Hello, World!"
 
 print :: String -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/5.hs b/tests/5.hs
--- a/tests/5.hs
+++ b/tests/5.hs
@@ -1,4 +1,4 @@
 main = print (2 * 4 / 2)
 
 print :: Double -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/6.hs b/tests/6.hs
--- a/tests/6.hs
+++ b/tests/6.hs
@@ -1,4 +1,4 @@
 main = print (10 + (2 * (4 / 2)))
 
 print :: Double -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/7.hs b/tests/7.hs
--- a/tests/7.hs
+++ b/tests/7.hs
@@ -1,4 +1,4 @@
 main = print True
 
 print :: Double -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
diff --git a/tests/8.hs b/tests/8.hs
--- a/tests/8.hs
+++ b/tests/8.hs
@@ -3,7 +3,7 @@
 main = print (head (fix (\xs -> 123 : xs)))
 
 print :: Double -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
 
 head (x:xs) = x
 
diff --git a/tests/9.hs b/tests/9.hs
--- a/tests/9.hs
+++ b/tests/9.hs
@@ -1,7 +1,7 @@
 main = print (head (tail (fix (\xs -> 123 : xs))))
 
 print :: Double -> Fay ()
-print = ffi "console.log(%1)" FayNone
+print = ffi "console.log(%1)"
 
 head (x:xs) = x