diff --git a/canvas_proxy.js b/canvas_proxy.js
new file mode 100644
index 000000000..1b100beae
--- /dev/null
+++ b/canvas_proxy.js
@@ -0,0 +1,109 @@
+function CanvasProxy(width, height) {
+    var stack = this.$stack = [];
+
+    // Expose only the minimum of the canvas object - there is no dom to do
+    // more here.
+    this.canvas = {
+        width: width,
+        height: height
+    }
+
+    var ctxFunc = [
+        "createRadialGradient",
+        "arcTo",
+        "arc",
+        "fillText",
+        "strokeText",
+        "drawImage",
+        "getImageData",
+        "putImageData",
+        "createImageData",
+        "drawWindow",
+        "save",
+        "restore",
+        "scale",
+        "rotate",
+        "translate",
+        "transform",
+        "setTransform",
+        "createLinearGradient",
+        "createPattern",
+        "clearRect",
+        "fillRect",
+        "strokeRect",
+        "beginPath",
+        "closePath",
+        "moveTo",
+        "lineTo",
+        "quadraticCurveTo",
+        "bezierCurveTo",
+        "rect",
+        "fill",
+        "stroke",
+        "clip",
+        "measureText",
+        "isPointInPath"
+    ];
+    function buildFuncCall(name) {
+        return function() {
+            console.log("funcCall", name)
+            stack.push([name, Array.prototype.slice.call(arguments)]);
+        }
+    }
+    var name;
+    for (var i = 0; i < ctxFunc.length; i++) {
+        name = ctxFunc[i];
+        this[name] = buildFuncCall(name);
+    }
+
+    var ctxProp = {
+        // "canvas"
+        "globalAlpha": "1",
+        "globalCompositeOperation": "source-over",
+        "strokeStyle": "#000000",
+        "fillStyle": "#000000",
+        "lineWidth": "1",
+        "lineCap": "butt",
+        "lineJoin": "miter",
+        "miterLimit": "10",
+        "shadowOffsetX": "0",
+        "shadowOffsetY": "0",
+        "shadowBlur": "0",
+        "shadowColor": "rgba(0, 0, 0, 0)",
+        "font": "10px sans-serif",
+        "textAlign": "start",
+        "textBaseline": "alphabetic",
+        "mozTextStyle": "10px sans-serif",
+        "mozImageSmoothingEnabled": "true",
+        "DRAWWINDOW_DRAW_CARET": "1",
+        "DRAWWINDOW_DO_NOT_FLUSH": "2",
+        "DRAWWINDOW_DRAW_VIEW": "4",
+        "DRAWWINDOW_USE_WIDGET_LAYERS": "8",
+        "DRAWWINDOW_ASYNC_DECODE_IMAGES": "16",
+    }
+
+    function buildGetter(name) {
+        return function() {
+            return this["$" + name];
+        }
+    }
+
+    function buildSetter(name) {
+        return function(value) {
+            stack.push(["$", name, value]);
+            return this["$" + name] = value;
+        }
+    }
+
+    for (var name in ctxProp) {
+        this["$" + name] = ctxProp[name];
+        this.__defineGetter__(name, buildGetter(name));
+        this.__defineSetter__(name, buildSetter(name));
+    }
+}
+
+CanvasProxy.prototype.flush = function() {
+    postMessage("canvas_proxy_stack");
+    postMessage(JSON.stringify(this.$stack));
+    this.$stack.length = 0;
+}
diff --git a/pdf.js b/pdf.js
index 326c31234..09d1c874e 100644
--- a/pdf.js
+++ b/pdf.js
@@ -2277,7 +2277,10 @@ var CanvasGraphics = (function() {
         this.pendingClip = null;
         this.res = null;
         this.xobjs = null;
-        this.map = {
+    }
+
+    constructor.prototype = {
+        map: {
             // Graphics state
             w: "setLineWidth",
             J: "setLineCap",
@@ -2634,7 +2637,9 @@ var CanvasGraphics = (function() {
             }
 
             var fn = Function("objpool", src);
-            return function (gfx) { fn.call(gfx, objpool); };
+            var ret = function (gfx) { fn.call(gfx, objpool); };
+            ret.src = src;
+            return ret;
         },
 
         endDrawing: function() {
@@ -3041,6 +3046,7 @@ var CanvasGraphics = (function() {
         shadingFill: function(entryRef) {
             var xref = this.xref;
             var res = this.res;
+
             var shadingRes = xref.fetchIfRef(res.get("Shading"));
             if (!shadingRes)
                 error("No shading resource found");
@@ -3468,6 +3474,7 @@ var ColorSpace = (function() {
                 break;
             case "ICCBased":
                 var dict = stream.dict;
+
                 this.stream = stream;
                 this.dict = dict;
                 this.numComps = dict.get("N");
@@ -3574,6 +3581,7 @@ var PDFFunction = (function() {
                     v = encode[i2] + ((v - domain[i2]) *
                                       (encode[i2 + 1] - encode[i2]) /
                                       (domain[i2 + 1] - domain[i2]));
+
                     // clip to the size
                     args[i] = clip(v, 0, size[i] - 1);
                 }
@@ -3601,6 +3609,7 @@ var PDFFunction = (function() {
                     // decode
                     v = decode[i2] + (v * (decode[i2 + 1] - decode[i2]) /
                                       ((1 << bps) - 1));
+
                     // clip to the domain
                     output.push(clip(v, range[i2], range[i2 + 1]));
                 }
diff --git a/viewer_worker.html b/viewer_worker.html
new file mode 100644
index 000000000..f9e1f0b32
--- /dev/null
+++ b/viewer_worker.html
@@ -0,0 +1,110 @@
+<html>
+    <head>
+        <title>Simple pdf.js page viewer worker</title>
+<script>
+var myWorker = new Worker('worker.js');
+
+// var array = new Uint8Array(2);
+// array[0] = 1;
+// array[1] = 300;
+//
+const WAIT = 0;
+const CANVAS_PROXY_STACK = 1;
+const LOG = 2;
+
+var onMessageState = WAIT;
+myWorker.onmessage = function(event) {
+    var data = event.data;
+    console.log("onMessageRaw", data);
+    switch (onMessageState) {
+        case WAIT:
+            if (typeof data != "string") {
+                throw "expecting to get an string";
+            }
+            switch (data) {
+                case "log":
+                    onMessageState = LOG;
+                    return;
+                case "canvas_proxy_stack":
+                    onMessageState = CANVAS_PROXY_STACK;
+                    return;
+                default:
+                    throw "unkown state: " + data
+            }
+            break;
+
+        case LOG:
+            console.log.apply(console, JSON.parse(data));
+            onMessageState = WAIT;
+            break;
+
+        case CANVAS_PROXY_STACK:
+            var stack = JSON.parse(data);
+            for (var i = 0; i < stack.length; i++) {
+                var opp = stack[i];
+                if (opp[0] == "$") {
+                    console.log("set property", opp[1], opp[2]);
+                    ctx[opp[1]] = opp[2];
+                } else {
+                    console.log("execute", opp[0], opp[1]);
+                    ctx[opp[0]].apply(ctx, opp[1]);
+                }
+            }
+            onMessageState = WAIT;
+            break;
+    }
+}
+//
+// myWorker.postMessage(array);
+
+function open(url) {
+    document.title = url;
+    var req = new XMLHttpRequest();
+    req.open("GET", url);
+    req.mozResponseType = req.responseType = "arraybuffer";
+    req.expected = (document.URL.indexOf("file:") == 0) ? 0 : 200;
+    req.onreadystatechange = function() {
+      if (req.readyState == 4 && req.status == req.expected) {
+        var data = req.mozResponseArrayBuffer || req.mozResponse ||
+                   req.responseArrayBuffer || req.response;
+        myWorker.postMessage(data);
+      }
+    };
+    req.send(null);
+}
+
+window.onload = function() {
+    var ctx = window.ctx = document.getElementById("canvas").getContext("2d");
+    // for (var name in ctx) {
+    //     if (!(ctx[name] instanceof Function)) {
+    //         console.log('"' + name + '": "' + ctx[name] + '",');
+    //     }
+    // }
+    open("compressed.tracemonkey-pldi-09.pdf");
+}
+</script>
+        <link rel="stylesheet" href="viewer.css"></link>
+  </head>
+
+  <body>
+    <div id="controls">
+    <input type="file" style="float: right; margin: auto 32px;" onChange="load(this.value.toString());"></input>
+    <!-- This only opens supported PDFs from the source path...
+      -- Can we use JSONP to overcome the same-origin restrictions? -->
+      <button onclick="prevPage();">Previous</button>
+      <button onclick="nextPage();">Next</button>
+      <input type="text" id="pageNumber" onchange="gotoPage(this.value);"
+             value="1" size="4"></input>
+      <span id="numPages">--</span>
+      <span id="info"></span>
+    </div>
+
+    <div id="viewer">
+      <!-- Canvas dimensions must be specified in CSS pixels.  CSS pixels
+           are always 96 dpi.  816x1056 is 8.5x11in at 96dpi. -->
+      <!-- We're rendering here at 1.5x scale. -->
+      <canvas id="canvas" width="1224" height="1584"></canvas>
+    </div>
+  </body>
+</html>
+
diff --git a/worker.js b/worker.js
new file mode 100644
index 000000000..fdc762afd
--- /dev/null
+++ b/worker.js
@@ -0,0 +1,113 @@
+"use strict";
+
+function log() {
+    var args = Array.prototype.slice.call(arguments);
+    postMessage("log");
+    postMessage(JSON.stringify(args))
+}
+
+var console = {
+    log: log
+}
+
+importScripts("canvas_proxy.js");
+importScripts("pdf.js");
+importScripts("fonts.js");
+importScripts("glyphlist.js")
+
+// var array = new Uint8Array(2);
+// array[0] = 1;
+// array[1] = 300;
+// postMessage(array);
+
+var timer = null;
+function tic() {
+    timer = Date.now();
+}
+
+function toc(msg) {
+    log("Took ", (Date.now() - timer));
+    timer = null;
+}
+
+
+var canvas = new CanvasProxy(1224, 1584);
+// canvas.moveTo(0, 10);
+// canvas.lineTo(0, 20);
+// canvas.lineTo(500, 500);
+// canvas.flush();
+// canvas.stroke();
+// canvas.flush();
+log("test");
+
+onmessage = function(event) {
+    var data = event.data;
+    var pdfDocument = new PDFDoc(new Stream(data));
+    var numPages = pdfDocument.numPages;
+
+    tic();
+    // Let's try to render the first page...
+    var page = pdfDocument.getPage(1);
+
+    // page.compile will collect all fonts for us, once we have loaded them
+    // we can trigger the actual page rendering with page.display
+    var fonts = [];
+
+    var gfx = new CanvasGraphics(canvas);
+    page.compile(gfx, fonts);
+    toc("compiled page");
+
+    //
+    var fontsReady = true;
+        // Inspect fonts and translate the missing one
+        var count = fonts.length;
+        for (var i = 0; i < count; i++) {
+          var font = fonts[i];
+          if (Fonts[font.name]) {
+            fontsReady = fontsReady && !Fonts[font.name].loading;
+            continue;
+          }
+
+          new Font(font.name, font.file, font.properties);
+          fontsReady = false;
+        }
+
+        function delayLoadFont() {
+          for (var i = 0; i < count; i++) {
+            if (Fonts[font.name].loading)
+              return;
+          }
+          clearInterval(pageInterval);
+          page.display(gfx);
+
+          canvas.flush();
+        };
+
+        if (fontsReady) {
+          delayLoadFont();
+        } else {
+          pageInterval = setInterval(delayLoadFont, 10);
+        }
+        postMessage(page.code.src);
+}
+
+// function open(url) {
+//     var req = new XMLHttpRequest();
+//     req.open("GET", url);
+//     // req.responseType = "arraybuffer";
+//     req.expected = 0;//(document.URL.indexOf("file:") == 0) ? 0 : 200;
+//     req.onreadystatechange = function() {
+//       postMessage("loaded");
+//       if (req.readyState == 4 && req.status == req.expected) {
+//         var data = req.mozResponseArrayBuffer || req.mozResponse ||
+//                    req.responseArrayBuffer || req.response;
+//         pdfDocument = new PDFDoc(new Stream(data));
+//         numPages = pdfDocument.numPages;
+//         // document.getElementById("numPages").innerHTML = numPages.toString();
+//         // goToPage(pageNum);
+//       }
+//     };
+//     req.send(null);
+// }
+//
+// open("compressed.tracemonkey-pldi-09.pdf")
\ No newline at end of file