diff --git a/proxy/snowflake.coffee b/proxy/snowflake.coffee
new file mode 100644
index 0000000..2723773
--- /dev/null
+++ b/proxy/snowflake.coffee
@@ -0,0 +1,471 @@
+###
+A Coffeescript WebRTC snowflake proxy
+Using Copy-paste signaling for now.
+
+Uses WebRTC from the client, and websocket to the server.
+
+Assume that the webrtc client plugin is always the offerer, in which case
+this must always act as the answerer.
+
+TODO(keroserene): Complete the websocket + webrtc ProxyPair
+###
+
+Query =
+  ###
+  Parse a URL query string or application/x-www-form-urlencoded body. The
+  return type is an object mapping string keys to string values. By design,
+  this function doesn't support multiple values for the same named parameter,
+  for example "a=1&a=2&a=3"; the first definition always wins. Returns null on
+  error.
+
+  Always decodes from UTF-8, not any other encoding.
+  http://dev.w3.org/html5/spec/Overview.html#url-encoded-form-data
+  ###
+  parse: (qs) ->
+    result = {}
+    strings = []
+    strings = qs.split '&' if qs
+    return result if 0 == strings.length
+    for i in [1..strings.length]
+      string = strings[i]
+      j = string.indexOf '='
+      if j == -1
+        name = string
+        value = ''
+      else
+        name = string.substr(0, j)
+        value = string.substr(j + 1)
+      name = decodeURIComponent(name.replace(/\+/g, ' '))
+      value = decodeURIComponent(value.replace(/\+/g, ' '))
+      result[name] = value if !(name in result)
+    result
+
+  # params is a list of (key, value) 2-tuples.
+  buildString: (params) ->
+    parts = []
+    for param in params
+      parts.push encodeURIComponent(param[0]) + '=' +
+                 encodeURIComponent(param[1])
+    parts.join '&'
+
+Params =
+  getBool: (query, param, defaultValue) ->
+    val = query[param]
+    return defaultValue if undefined == val
+    return true if "true" == val || "1" == val || "" == val
+    return false if "false" == val || "0" == val
+    return null
+
+# repr = (x) ->
+  # return 'null' if null == x
+  # return 'undefined' if 'undefined' == typeof x
+  # if 'object' == typeof x
+    # elems = []
+    # for k in x
+      # elems.push(maybe_quote(k) + ': ' + repr(x[k]));
+    # return "{ " + elems.join(", ") + " }";
+  # } else if (typeof x === "string") {
+    # return quote(x);
+  # } else {
+    # return x.toString();
+# safe_repr = (s) -> SAFE_LOGGING ? "[scrubbed]" : repr(s)
+safe_repr = (s) -> SAFE_LOGGING ? "[scrubbed]" : JSON.stringify(s)
+
+# HEADLESS is true if we are running not in a browser with a DOM.
+query = Query.parse(window.location.search.substr(1))
+HEADLESS = "undefined" == typeof(document)
+DEBUG = Params.getBool(query, "debug", false)
+
+# TODO: Different ICE servers.
+config = {
+  iceServers: [
+    { urls: ["stun:stun.l.google.com:19302"] }
+  ]
+}
+
+# DOM elements
+$chatlog = null
+$send = null
+$input = null
+
+window.PeerConnection = window.RTCPeerConnection ||
+                        window.mozRTCPeerConnection ||
+                        window.webkitRTCPeerConnection
+window.RTCIceCandidate = window.RTCIceCandidate || window.mozRTCIceCandidate;
+window.RTCSessionDescription = window.RTCSessionDescription ||
+                               window.mozRTCSessionDescription
+
+# TODO: Implement
+class Badge
+
+
+# Janky state machine
+MODE =
+  INIT:              0
+  WEBRTC_CONNECTING: 1
+  WEBRTC_READY:      2
+
+# Minimum viable snowflake for now - just 1 client.
+class Snowflake
+
+  # PeerConnection
+  pc: null
+  rateLimit: 0
+  proxyPairs: []
+  badge: null
+  $badge: null
+  MAX_NUM_CLIENTS = 1
+  CONNECTIONS_PER_CLIENT = 1
+  state: MODE.INIT
+
+  constructor: ->
+    if HEADLESS
+      # No badge
+    else if DEBUG
+      @$badge = debug_div
+    else
+      @badge = new Badge()
+      @$badgem = @badge.elem
+    if (@$badge)
+      @$badge.setAttribute("id", "snowflake-badge")
+
+  # Initialize WebRTC PeerConnection
+  beginWebRTC: ->
+    log "Starting up Snowflake..."
+    @state = MODE.WEBRTC_CONNECTING
+
+    @pc = new PeerConnection(config, {
+      optional: [
+        { DtlsSrtpKeyAgreement: true }
+        { RtpDataChannels: false }
+      ]
+    })
+
+    @pc.onicecandidate = (evt) =>
+      # Browser sends a null candidate once the ICE gathering completes.
+      # In this case, it makes sense to send one copy-paste blob.
+      if null == evt.candidate
+        log "Finished gathering ICE candidates."
+        Signalling.send @pc.localDescription
+
+    # OnDataChannel triggered remotely from the client when connection succeeds.
+    @pc.ondatachannel = (dc) =>
+      console.log dc;
+      channel = dc.channel
+      log "Data Channel established..."
+      @prepareDataChannel channel
+
+  prepareDataChannel: (channel) ->
+    channel.onopen = =>
+      log "Data channel opened!"
+      @state = MODE.WEBRTC_READY
+      # TODO: Prepare ProxyPair onw.
+      @beginProxy()
+    channel.onclose = =>
+      log "Data channel closed."
+      @state = MODE.INIT;
+      $chatlog.className = ""
+    channel.onerror = =>
+      log "Data channel error!"
+    channel.onmessage = (msg) =>
+      line = recv = msg.data
+      console.log(msg);
+      # Go sends only raw bytes...
+      if "[object ArrayBuffer]" == recv.toString()
+        bytes = new Uint8Array recv
+        line = String.fromCharCode.apply(null, bytes)
+      line = line.trim()
+      log "data: " + line
+
+  # Receive an SDP offer from client plugin.
+  receiveOffer: (desc) =>
+    sdp = new RTCSessionDescription desc
+    try
+      err = @pc.setRemoteDescription sdp
+    catch e
+      log "Invalid SDP message."
+      return false
+    log("SDP " + sdp.type + " successfully received.")
+    @sendAnswer() if 'offer' == sdp.type
+    true
+
+  sendAnswer: =>
+    next = (sdp) =>
+      log "webrtc: Answer ready."
+      @pc.setLocalDescription sdp
+    promise = @pc.createAnswer next
+    promise.then next if promise
+
+  # Poll facilitator when this snowflake can support more clients.
+  proxyMain: ->
+    if @proxyPairs.length >= @MAX_NUM_CLIENTS * @CONNECTIONS_PER_CLIENT
+      setTimeout(@proxyMain, @facilitator_poll_interval * 1000)
+      return
+
+    params = [["r", "1"]]
+    params.push ["transport", "websocket"]
+    params.push ["transport", "webrtc"]
+
+  beginProxy: (client, relay) ->
+    for i in [1..CONNECTIONS_PER_CLIENT]
+      @makeProxyPair client, relay
+
+  makeProxyPair: (client, relay) ->
+    pair = new ProxyPair(client, relay, @rate_limit);
+    @proxyPairs.push pair
+    pair.onCleanup = (event) =>
+      # Delete from the list of active proxy pairs.
+      @proxyPairs.splice(@proxy_pairs.indexOf(pair), 1)
+      @badge.endProxy() if @badge
+    try
+      pair.connectRelay()
+    catch err
+      log 'ERROR: ProxyPair exception while connecting.'
+      log err
+      return
+    @badge.beginProxy if @badge
+
+  cease: ->
+    while @proxyPairs.length > 0
+      @proxyPairs.pop().close()
+
+  disable: ->
+    log "Disabling Snowflake."
+    @cease()
+    @badge.disable() if @badge
+
+  die: ->
+    log "Snowflake died."
+    @cease()
+    @badge.die() if @badge
+
+
+# Build an escaped URL string from unescaped components. Only scheme and host
+# are required. See RFC 3986, section 3.
+buildUrl = (scheme, host, port, path, params) ->
+  parts = []
+  parts.push(encodeURIComponent scheme)
+  parts.push '://'
+
+  # If it contains a colon but no square brackets, treat it as IPv6.
+  if host.match(/:/) && !host.match(/[[\]]/)
+    parts.push '['
+    parts.push host
+    parts.push ']'
+  else
+    parts.push(encodeURIComponent host)
+
+  if undefined != port && DEFAULT_PORTS[scheme] != port
+    parts.push ':'
+    parts.push(encodeURIComponent port.toString())
+
+  if undefined != path && '' != path
+    if !path.match(/^\//)
+      path = '/' + path
+    ###
+    Slash is significant so we must protect it from encodeURIComponent, while
+    still encoding question mark and number sign. RFC 3986, section 3.3: "The
+    path is terminated by the first question mark ('?') or number sign ('#')
+    character, or by the end of the URI. ... A path consists of a sequence of
+    path segments separated by a slash ('/') character."
+    ###
+    path = path.replace /[^\/]+/, (m) ->
+      encodeURIComponent m
+    parts.push path
+
+  if undefined != params
+    parts.push '?'
+    parts.push Query.buildString params
+
+  parts.join ''
+
+makeWebsocket = (addr) ->
+  url = buildUrl 'ws', addr.host, addr.port, '/'
+  if have_websocket_binary_frames()
+    ws = new WebSocket url
+  else
+    ws = new WebSocket url 'base64'
+  ###
+  "User agents can use this as a hint for how to handle incoming binary data: if
+  the attribute is set to 'blob', it is safe to spool it to disk, and if it is
+  set to 'arraybuffer', it is likely more efficient to keep the data in memory."
+  ###
+  ws.binaryType = 'arraybuffer'
+  ws
+
+
+
+# TODO: Implement
+class ProxyPair
+
+  # TODO: Hardcoded for now, but should fetch from facilitator later.
+  relayAddr: null
+
+  constructor: (@clientAddr, @relayAddr, @rateLimit) ->
+
+  # Assumes WebRTC part is already connected.
+  # TODO: Put the webrtc stuff in ProxyPair, so that multiple webrtc connections
+  # can be established.
+  connectRelay: ->
+    log "Snowflake: connecting to relay"
+
+    @relay = makeWebsocket(@relayAddr);
+    @relay.label = 'Relay'
+    @relay.onopen = =>
+      log "Snowflake: " + ws.label + "connected"
+    @relay.onclose = @onClose
+    @relay.onerror = @onError
+    @relay.onmessage = @onRelayToClientMessage
+
+  onClientToRelayMessage: (event) ->
+    @c2r_schedule.push event.data
+    @flush()
+
+  onRelayToClientMessage: (event) ->
+    @r2c_schedule.push event.data
+    @flush()
+
+  onClose: (event) ->
+    ws = event.target
+    log(ws.label + ': closed.')
+    @flush()
+    @maybeCleanup()
+
+  onError: (event) ->
+    ws = event.target
+    log ws.label + ': error.'
+    this.close();
+    # we can't rely on onclose_callback to cleanup, since one common error
+    # case is when the client fails to connect and the relay never starts.
+    # in that case close() is a NOP and onclose_callback is never called.
+    @maybeCleanup()
+
+  isOpen:   (ws) -> undefined != ws && WebSocket.OPEN   == ws.readyState
+  isClosed: (ws) -> undefined == ws || WebSocket.CLOSED == ws.readyState
+
+  maybe_cleanup: ->
+    if @running && @isClosed(client) && @isClosed @relay 
+      @running = false
+      @cleanup_callback()
+      true
+    false
+
+  # Send as much data as the rate limit currently allows.
+  ###
+  flush: ->
+    clearTimeout @flush_timeout_id if @flush_timeout_id
+    @flush_timeout_id = null
+    busy = true
+    checkChunks = ->
+      busy = false
+      # if @isOpen @clientthis.client_s) &&
+          # this.client_s.bufferedAmount < MAX_BUFFER &&
+          # this.r2c_schedule.length > 0) {
+        # chunk = this.r2c_schedule.shift();
+        # this.rate_limit.update(chunk.length);
+        # this.client_s.send(chunk);
+        # busy = true;
+      #
+      if @isOpen @relay &&
+        @relay.bufferedAmount < MAX_BUFFER &&
+        @c2r_schedule.length > 0
+        chunk = @c2r_schedule.shift()
+        @rate_limit.update chunk.length
+        @relay.send chunk
+        busy = true
+    checkChunks() while busy && !@rate_limit.is_limited()
+
+    if @isClosed @relay &&
+        # !isClosed(this.client_s) &&
+        # @client_s.bufferedAmount === 0 &&
+        @r2c_schedule.length == 0
+      # log("Client: closing.");
+      # this.client_s.close();
+      # if (is_closed(this.client_s) &&
+        # !is_closed(this.relay_s) &&
+        # this.relay_s.bufferedAmount === 0 &&
+        # this.c2r_schedule.length === 0) {
+      # log("Relay: closing.");
+      # this.relay_s.close();
+    # }
+
+
+    while busy && !@rate_limit.is_limited()
+
+    if this.r2c_schedule.length > 0 ||
+      (@isOpen(@client) && @client.bufferedAmount > 0) ||
+      @c2r_schedule.length > 0 ||
+      (@isOpen(@relay) && @relay.bufferedAmount > 0)
+      @flush_timeout_id = setTimeout @flush, @rate_limit.when() * 1000
+  ###
+#
+## -- DOM & Input Functionality -- ##
+#
+snowflake = null
+
+welcome = ->
+  log "== snowflake browser proxy =="
+  log "Input offer from the snowflake client:"
+
+# Log to the message window.
+log = (msg) ->
+  $chatlog.value += msg + "\n"
+  console.log msg
+  # Scroll to latest
+  $chatlog.scrollTop = $chatlog.scrollHeight
+
+Interface =
+  # Local input from keyboard into message window.
+  acceptInput: ->
+    msg = $input.value
+    switch snowflake.state
+      when MODE.WEBRTC_CONNECTING
+        Signalling.receive msg
+      when MODE.WEBRTC_READY
+        log "No input expected - WebRTC connected."
+        # data = msg
+        # log(data)
+        # channel.send(data)
+      else
+        log "ERROR: " + msg
+    $input.value = ""
+    $input.focus()
+
+# Signalling channel - just tells user to copy paste to the peer.
+# Eventually this should go over the facilitator.
+Signalling =
+  send: (msg) ->
+    log "---- Please copy the below to peer ----\n"
+    log JSON.stringify(msg)
+    log "\n"
+
+  receive: (msg) ->
+    recv = ""
+    try
+      recv = JSON.parse msg
+    catch e
+      log "Invalid JSON."
+      return
+    desc = recv['sdp']
+    if !desc
+      log "Invalid SDP."
+      return false
+    snowflake.receiveOffer recv if desc
+
+init = ->
+  $chatlog = document.getElementById('chatlog')
+  $chatlog.value = ""
+
+  $send = document.getElementById('send')
+  $send.onclick = Interface.acceptInput
+
+  $input = document.getElementById('input')
+  $input.focus()
+  $input.onkeydown = (e) =>
+    if 13 == e.keyCode  # enter
+      $send.onclick()
+  snowflake = new Snowflake()
+  snowflake.beginWebRTC()
+  welcome()
+
+window.onload = init
diff --git a/proxy/snowflake.html b/proxy/snowflake.html
index cff00a9..55adc42 100644
--- a/proxy/snowflake.html
+++ b/proxy/snowflake.html
@@ -2,7 +2,8 @@
 <html>
 <head>
   <meta content="text/html;charset=utf-8" http-equiv="Content-Type">
-  <script src="snowflake.js"></script>
+  <script type="text/javascript" src="lib/coffee-script.js"></script>
+  <script type="text/coffeescript" src="snowflake.coffee"></script>
   <style>
   * {
     box-sizing: border-box;
diff --git a/proxy/snowflake.js b/proxy/snowflake.js
deleted file mode 100644
index 6d66673..0000000
--- a/proxy/snowflake.js
+++ /dev/null
@@ -1,562 +0,0 @@
-/*
-JS WebRTC proxy
-Copy-paste signaling.
-*/
-
-// DOM elements
-var $chatlog, $input, $send, $name;
-
-var config = {
-  iceServers: [
-    { urls: ["stun:stun.l.google.com:19302"] }
-  ]
-}
-
-// Chrome / Firefox compatibility
-window.PeerConnection = window.RTCPeerConnection ||
-                        window.mozRTCPeerConnection || window.webkitRTCPeerConnection;
-window.RTCIceCandidate = window.RTCIceCandidate || window.mozRTCIceCandidate;
-window.RTCSessionDescription = window.RTCSessionDescription || window.mozRTCSessionDescription;
-
-var pc;  // PeerConnection
-var offer, answer;
-var channel;
-
-// Janky state machine
-var MODE = {
-  INIT:       0,
-  CONNECTING: 1,
-  CHAT:       2
-}
-var currentMode = MODE.INIT;
-var CONNECTIONS_PER_CLIENT = 2;
-
-// Signalling channel - just tells user to copy paste to the peer.
-// Eventually this should go over the facilitator.
-var Signalling = {
-  send: function(msg) {
-    log("---- Please copy the below to peer ----\n");
-    log(JSON.stringify(msg));
-    log("\n");
-  },
-  receive: function(msg) {
-    var recv;
-    try {
-      recv = JSON.parse(msg);
-    } catch(e) {
-      log("Invalid JSON.");
-      return;
-    }
-    if (!pc) {
-      start(false);
-    }
-    var desc = recv['sdp']
-    var ice = recv['candidate']
-    if (!desc && ! ice) {
-      log("Invalid SDP.");
-      return false;
-    }
-    if (desc) { receiveDescription(recv); }
-    if (ice) { receiveICE(recv); }
-  }
-}
-
-function welcome() {
-  log("== snowflake JS proxy ==");
-  log("Input offer from the snowflake client:");
-}
-
-function start(initiator) {
-  log("Starting up RTCPeerConnection...");
-  pc = new PeerConnection(config, {
-    optional: [
-      { DtlsSrtpKeyAgreement: true },
-      { RtpDataChannels: false },
-    ],
-  });
-  pc.onicecandidate = function(evt) {
-    var candidate = evt.candidate;
-    // Chrome sends a null candidate once the ICE gathering phase completes.
-    // In this case, it makes sense to send one copy-paste blob.
-    if (null == candidate) {
-      log("Finished gathering ICE candidates.");
-      Signalling.send(pc.localDescription);
-      return;
-    }
-  }
-  pc.onnegotiationneeded = function() {
-    sendOffer();
-  }
-  pc.ondatachannel = function(dc) {
-    console.log(dc);
-    channel = dc.channel;
-    log("Data Channel established... ");
-    prepareDataChannel(channel);
-  }
-
-  // Creating the first data channel triggers ICE negotiation.
-  if (initiator) {
-    channel = pc.createDataChannel("test");
-    prepareDataChannel(channel);
-  }
-}
-
-// Local input from keyboard into chat window.
-function acceptInput(is) {
-  var msg = $input.value;
-  switch (currentMode) {
-    case MODE.INIT:
-      if (msg.startsWith("start")) {
-        start(true);
-      } else {
-        Signalling.receive(msg);
-      }
-      break;
-    case MODE.CONNECTING:
-      Signalling.receive(msg);
-      break;
-    case MODE.CHAT:
-      var data = msg;
-      log(data);
-      channel.send(data);
-      break;
-    default:
-      log("ERROR: " + msg);
-  }
-  $input.value = "";
-  $input.focus();
-}
-
-// Chrome uses callbacks while Firefox uses promises.
-// Need to support both - same for createAnswer below.
-function sendOffer() {
-  var next = function(sdp) {
-    log("webrtc: Created Offer");
-    offer = sdp;
-    pc.setLocalDescription(sdp);
-  }
-  var promise = pc.createOffer(next);
-  if (promise) {
-    promise.then(next);
-  }
-}
-
-function sendAnswer() {
-  var next = function (sdp) {
-    log("webrtc: Created Answer");
-    answer = sdp;
-    pc.setLocalDescription(sdp)
-  }
-  var promise = pc.createAnswer(next);
-  if (promise) {
-    promise.then(next);
-  }
-}
-
-function receiveDescription(desc) {
-  var sdp = new RTCSessionDescription(desc);
-  try {
-    err = pc.setRemoteDescription(sdp);
-  } catch (e) {
-    log("Invalid SDP message.");
-    return false;
-  }
-  log("SDP " + sdp.type + " successfully received.");
-  if ("offer" == sdp.type) {
-    sendAnswer();
-  }
-  return true;
-}
-
-function receiveICE(ice) {
-  var candidate = new RTCIceCandidate(ice);
-  try {
-    pc.addIceCandidate(candidate);
-  } catch (e) {
-    log("Could not add ICE candidate.");
-    return;
-  }
-  log("ICE candidate successfully received: " + ice.candidate);
-}
-
-function waitForSignals() {
-  currentMode = MODE.CONNECTING;
-}
-
-function prepareDataChannel(channel) {
-  channel.onopen = function() {
-    log("Data channel opened!");
-    startChat();
-  }
-  channel.onclose = function() {
-    log("Data channel closed.");
-    currentMode = MODE.INIT;
-    $chatlog.className = "";
-    log("------- chat disabled -------");
-  }
-  channel.onerror = function() {
-    log("Data channel error!!");
-  }
-  channel.onmessage = function(msg) {
-    var recv = msg.data;
-    console.log(msg);
-    // Go sends only raw bytes.
-    if ("[object ArrayBuffer]" == recv.toString()) {
-      var bytes = new Uint8Array(recv);
-      line = String.fromCharCode.apply(null, bytes);
-    } else {
-      line = recv;
-    }
-    line = line.trim();
-    log(line);
-  }
-}
-
-function startChat() {
-  currentMode = MODE.CHAT;
-  $chatlog.className = "active";
-  log("------- chat enabled! -------");
-}
-
-// Get DOM elements and setup interactions.
-function init() {
-  console.log("loaded");
-  // Setup chatwindow.
-  $chatlog = document.getElementById('chatlog');
-  $chatlog.value = "";
-
-  $send = document.getElementById('send');
-  $send.onclick = acceptInput
-
-  $input = document.getElementById('input');
-  $input.focus();
-  $input.onkeydown = function(e) {
-    if (13 == e.keyCode) {  // enter
-      $send.onclick();
-    }
-  }
-  welcome();
-}
-
-var log = function(msg) {
-  $chatlog.value += msg + "\n";
-  console.log(msg);
-  // Scroll to latest.
-  $chatlog.scrollTop = $chatlog.scrollHeight;
-}
-
-window.onload = init;
-
-//
-// some code sourced from flashproxy.js
-// TODO: refactor / webrtc-afy it
-//
-
-/* Does the WebSocket implementation in this browser support binary frames? (RFC
-   6455 section 5.6.) If not, we have to use base64-encoded text frames. It is
-   assumed that the client and relay endpoints always support binary frames. */
-function have_websocket_binary_frames() {
-  var BROWSERS = [
-    { idString: "Chrome", verString: "Chrome", version: 16 },
-    { idString: "Safari", verString: "Version", version: 6 },
-    { idString: "Firefox", verString: "Firefox", version: 11 }
-  ];
-  var ua;
-
-  ua = window.navigator.userAgent;
-  if (!ua)
-    return false;
-
-  for (var i = 0; i < BROWSERS.length; i++) {
-    var matches, reg;
-
-    reg = "\\b" + BROWSERS[i].idString + "\\b";
-    if (!ua.match(new RegExp(reg, "i")))
-        continue;
-    reg = "\\b" + BROWSERS[i].verString + "\\/(\\d+)";
-    matches = ua.match(new RegExp(reg, "i"));
-    return matches !== null && Number(matches[1]) >= BROWSERS[i].version;
-  }
-
-  return false;
-}
-
-function make_websocket(addr) {
-  var url;
-  var ws;
-
-  url = build_url("ws", addr.host, addr.port, "/");
-
-  if (have_websocket_binary_frames())
-    ws = new WebSocket(url);
-  else
-    ws = new WebSocket(url, "base64");
-  /* "User agents can use this as a hint for how to handle incoming binary
-     data: if the attribute is set to 'blob', it is safe to spool it to disk,
-     and if it is set to 'arraybuffer', it is likely more efficient to keep
-     the data in memory." */
-  ws.binaryType = "arraybuffer";
-
-  return ws;
-}
-
-function Snowflake() {
-  if (HEADLESS) {
-    /* No badge. */
-  } else if (DEBUG) {
-    this.badge_elem = debug_div;
-  } else {
-    this.badge = new Badge();
-    this.badge_elem = this.badge.elem;
-  }
-  if (this.badge_elem)
-    this.badge_elem.setAttribute("id", "flashproxy-badge");
-
-  this.proxy_pairs = [];
-
-  this.start = function() {
-    var client_addr;
-    var relay_addr;
-    var rate_limit_bytes;
-    log("Snowflake starting.")
-    // TODO: Facilitator interaction
-  };
-
-  this.proxy_main = function() {
-    var params;
-    var base_url, url;
-    var xhr;
-
-    if (this.proxy_pairs.length >= this.max_num_clients * CONNECTIONS_PER_CLIENT) {
-      setTimeout(this.proxy_main.bind(this), this.facilitator_poll_interval * 1000);
-      return;
-    }
-
-    params = [["r", "1"]];
-    params.push(["transport", "websocket"]);
-    params.push(["transport", "webrtc"]);
-  };
-
-  this.begin_proxy = function(client_addr, relay_addr) {
-    for (var i=0; i<CONNECTIONS_PER_CLIENT; i++) {
-      this.make_proxy_pair(client_addr, relay_addr);
-    }
-  };
-
-  this.make_proxy_pair = function(client_addr, relay_addr) {
-    var proxy_pair;
-
-    proxy_pair = new ProxyPair(client_addr, relay_addr, this.rate_limit);
-    this.proxy_pairs.push(proxy_pair);
-    proxy_pair.cleanup_callback = function(event) {
-        /* Delete from the list of active proxy pairs. */
-        this.proxy_pairs.splice(this.proxy_pairs.indexOf(proxy_pair), 1);
-        if (this.badge)
-            this.badge.proxy_end();
-    }.bind(this);
-    try {
-        proxy_pair.connect();
-    } catch (err) {
-        puts("ProxyPair: exception while connecting: " + safe_repr(err.message) + ".");
-        return;
-    }
-
-    if (this.badge)
-        this.badge.proxy_begin();
-  };
-
-  /* Cease all network operations and prevent any future ones. */
-  this.cease_operation = function() {
-    this.start = function() { };
-    this.proxy_main = function() { };
-    this.make_proxy_pair = function(client_addr, relay_addr) { };
-    while (this.proxy_pairs.length > 0)
-      this.proxy_pairs.pop().close();
-  };
-
-  this.disable = function() {
-    puts("Disabling.");
-    this.cease_operation();
-    if (this.badge)
-      this.badge.disable();
-  };
-
-  this.die = function() {
-    puts("Dying.");
-    this.cease_operation();
-    if (this.badge)
-      this.badge.die();
-  };
-}
-
-/* An instance of a client-relay connection. */
-function ProxyPair(client_addr, relay_addr, rate_limit) {
-  var MAX_BUFFER = 10 * 1024 * 1024;
-
-  function log(s) {
-    if (!SAFE_LOGGING) {
-        s = format_addr(client_addr) + '|' + format_addr(relay_addr) + ' : ' + s
-    }
-    // puts(s)
-    window.log(s)
-  }
-
-  this.client_addr = client_addr;
-  this.relay_addr = relay_addr;
-  this.rate_limit = rate_limit;
-
-  this.c2r_schedule = [];
-  this.r2c_schedule = [];
-
-  this.running = true;
-  this.flush_timeout_id = null;
-
-  /* This callback function can be overridden by external callers. */
-  this.cleanup_callback = function() {
-  };
-
-  this.connect = function() {
-    log("Client: connecting.");
-    this.client_s = make_websocket(this.client_addr);
-
-    /* Try to connect to the client first (since that is more likely to
-       fail) and only after that try to connect to the relay. */
-    this.client_s.label = "Client";
-    this.client_s.onopen = this.client_onopen_callback;
-    this.client_s.onclose = this.onclose_callback;
-    this.client_s.onerror = this.onerror_callback;
-    this.client_s.onmessage = this.onmessage_client_to_relay;
-  };
-
-  this.client_onopen_callback = function(event) {
-    var ws = event.target;
-
-    log(ws.label + ": connected.");
-    log("Relay: connecting.");
-    this.relay_s = make_websocket(this.relay_addr);
-
-    this.relay_s.label = "Relay";
-    this.relay_s.onopen = this.relay_onopen_callback;
-    this.relay_s.onclose = this.onclose_callback;
-    this.relay_s.onerror = this.onerror_callback;
-    this.relay_s.onmessage = this.onmessage_relay_to_client;
-  }.bind(this);
-
-  this.relay_onopen_callback = function(event) {
-    var ws = event.target;
-
-    log(ws.label + ": connected.");
-  }.bind(this);
-
-  this.maybe_cleanup = function() {
-    if (this.running && is_closed(this.client_s) && is_closed(this.relay_s)) {
-        this.running = false;
-        this.cleanup_callback();
-        return true;
-    }
-    return false;
-  }
-
-  this.onclose_callback = function(event) {
-    var ws = event.target;
-
-    log(ws.label + ": closed.");
-    this.flush();
-
-    if (this.maybe_cleanup()) {
-        puts("Complete.");
-    }
-  }.bind(this);
-
-  this.onerror_callback = function(event) {
-    var ws = event.target;
-
-    log(ws.label + ": error.");
-    this.close();
-
-    // we can't rely on onclose_callback to cleanup, since one common error
-    // case is when the client fails to connect and the relay never starts.
-    // in that case close() is a NOP and onclose_callback is never called.
-    this.maybe_cleanup();
-  }.bind(this);
-
-  this.onmessage_client_to_relay = function(event) {
-    this.c2r_schedule.push(event.data);
-    this.flush();
-  }.bind(this);
-
-  this.onmessage_relay_to_client = function(event) {
-    this.r2c_schedule.push(event.data);
-    this.flush();
-  }.bind(this);
-
-  function is_open(ws) {
-    return ws !== undefined && ws.readyState === WebSocket.OPEN;
-  }
-
-  function is_closed(ws) {
-    return ws === undefined || ws.readyState === WebSocket.CLOSED;
-  }
-
-  this.close = function() {
-    if (!is_closed(this.client_s))
-        this.client_s.close();
-    if (!is_closed(this.relay_s))
-        this.relay_s.close();
-  };
-
-  /* Send as much data as the rate limit currently allows. */
-  this.flush = function() {
-    var busy;
-
-    if (this.flush_timeout_id)
-        clearTimeout(this.flush_timeout_id);
-    this.flush_timeout_id = null;
-
-    busy = true;
-    while (busy && !this.rate_limit.is_limited()) {
-      var chunk;
-      busy = false;
-
-      if (is_open(this.client_s) &&
-          this.client_s.bufferedAmount < MAX_BUFFER &&
-          this.r2c_schedule.length > 0) {
-        chunk = this.r2c_schedule.shift();
-        this.rate_limit.update(chunk.length);
-        this.client_s.send(chunk);
-        busy = true;
-      }
-      if (is_open(this.relay_s) &&
-          this.relay_s.bufferedAmount < MAX_BUFFER &&
-          this.c2r_schedule.length > 0) {
-        chunk = this.c2r_schedule.shift();
-        this.rate_limit.update(chunk.length);
-        this.relay_s.send(chunk);
-        busy = true;
-      }
-    }
-
-    if (is_closed(this.relay_s) &&
-        !is_closed(this.client_s) &&
-        this.client_s.bufferedAmount === 0 &&
-        this.r2c_schedule.length === 0) {
-      log("Client: closing.");
-      this.client_s.close();
-    }
-    if (is_closed(this.client_s) &&
-        !is_closed(this.relay_s) &&
-        this.relay_s.bufferedAmount === 0 &&
-        this.c2r_schedule.length === 0) {
-      log("Relay: closing.");
-      this.relay_s.close();
-    }
-
-    if (this.r2c_schedule.length > 0 ||
-        (is_open(this.client_s) && this.client_s.bufferedAmount > 0) ||
-        this.c2r_schedule.length > 0 ||
-        (is_open(this.relay_s) && this.relay_s.bufferedAmount > 0))
-      this.flush_timeout_id = setTimeout(
-        this.flush.bind(this), this.rate_limit.when() * 1000);
-  };
-}
-