diff --git a/client.js b/client.js
index 93e81db..1e9d974 100644
--- a/client.js
+++ b/client.js
@@ -1,7 +1,8 @@
 module.exports = Client
 
-var EventEmitter = require('events').EventEmitter
 var debug = require('debug')('bittorrent-tracker')
+var EventEmitter = require('events').EventEmitter
+var extend = require('xtend')
 var inherits = require('inherits')
 var once = require('once')
 var parallel = require('run-parallel')
@@ -20,12 +21,13 @@ inherits(Client, EventEmitter)
  *
  * Find torrent peers, to help a torrent client participate in a torrent swarm.
  *
- * @param {string|Buffer} peerId   peer id
- * @param {Number} port            torrent client listening port
- * @param {Object} torrent         parsed torrent
- * @param {Object} opts            options object
- * @param {Number} opts.rtcConfig  RTCPeerConnection configuration object
- * @param {Number} opts.wrtc       custom webrtc implementation
+ * @param {string|Buffer} peerId         peer id
+ * @param {Number} port                  torrent client listening port
+ * @param {Object} torrent               parsed torrent
+ * @param {Object} opts                  options object
+ * @param {Number} opts.rtcConfig        RTCPeerConnection configuration object
+ * @param {Number} opts.wrtc             custom webrtc implementation
+ * @param {Object} opts.getAnnounceOpts  callback to provide data to tracker
  */
 function Client (peerId, port, torrent, opts) {
   var self = this
@@ -270,9 +272,7 @@ Client.prototype._defaultAnnounceOpts = function (opts) {
     opts.left = self.torrentLength - opts.downloaded
   }
 
-  if (opts.getAnnounceOpts == null) {
-    opts.getAnnounceOpts = self._getAnnounceOpts
-  }
+  if (self._getAnnounceOpts) opts = extend(opts, self._getAnnounceOpts())
 
   return opts
 }
diff --git a/lib/client/http-tracker.js b/lib/client/http-tracker.js
index 8e19c27..c8be443 100644
--- a/lib/client/http-tracker.js
+++ b/lib/client/http-tracker.js
@@ -3,6 +3,7 @@ module.exports = HTTPTracker
 var bencode = require('bencode')
 var compact2string = require('compact2string')
 var debug = require('debug')('bittorrent-tracker:http-tracker')
+var extend = require('xtend')
 var get = require('simple-get')
 var inherits = require('inherits')
 
@@ -40,27 +41,12 @@ HTTPTracker.prototype.announce = function (opts) {
   var self = this
   if (self.destroyed) return
 
-  // Refresh opts if the callback is provided
-  var cbopts
-  if (opts.getAnnounceOpts) {
-    cbopts = opts.getAnnounceOpts()
-    if (cbopts.uploaded) opts.uploaded = cbopts.uploaded
-    if (cbopts.downloaded) opts.downloaded = cbopts.downloaded
-    if (cbopts.left) opts.left = cbopts.left
-  }
-
-  var params = {
-    numwant: opts.numwant,
-    uploaded: opts.uploaded,
-    downloaded: opts.downloaded,
-    left: opts.left,
-    event: opts.event,
+  var params = extend(opts, {
     compact: (opts.compact == null) ? 1 : opts.compact,
     info_hash: self.client._infoHashBinary,
     peer_id: self.client._peerIdBinary,
-    port: self.client._port,
-    extras: cbopts && cbopts.extraAnnounceOpts
-  }
+    port: self.client._port
+  })
   if (self._trackerId) params.trackerid = self._trackerId
 
   self._request(self.announceUrl, params, self._onAnnounceResponse.bind(self))
diff --git a/lib/client/udp-tracker.js b/lib/client/udp-tracker.js
index 34e2a2c..4bd98a5 100644
--- a/lib/client/udp-tracker.js
+++ b/lib/client/udp-tracker.js
@@ -189,15 +189,6 @@ UDPTracker.prototype._request = function (opts) {
   function announce (connectionId, opts) {
     transactionId = genTransactionId()
 
-    // Refresh opts if the callback is provided
-    var cbopts
-    if (opts.getAnnounceOpts) {
-      cbopts = opts.getAnnounceOpts()
-      if (cbopts.uploaded) opts.uploaded = cbopts.uploaded
-      if (cbopts.downloaded) opts.downloaded = cbopts.downloaded
-      if (cbopts.left) opts.left = cbopts.left
-    }
-
     send(Buffer.concat([
       connectionId,
       common.toUInt32(common.ACTIONS.ANNOUNCE),
diff --git a/lib/client/websocket-tracker.js b/lib/client/websocket-tracker.js
index ba93f3d..8b00aaf 100644
--- a/lib/client/websocket-tracker.js
+++ b/lib/client/websocket-tracker.js
@@ -1,6 +1,7 @@
 module.exports = WebSocketTracker
 
 var debug = require('debug')('bittorrent-tracker:websocket-tracker')
+var extend = require('xtend')
 var hat = require('hat')
 var inherits = require('inherits')
 var Peer = require('simple-peer')
@@ -44,27 +45,13 @@ WebSocketTracker.prototype.announce = function (opts) {
   // Limit the number of offers that are generated, since it can be slow
   var numwant = Math.min(opts.numwant, 10)
 
-  // Refresh opts if the callback is provided
-  var cbopts
-  if (opts.getAnnounceOpts) {
-    cbopts = opts.getAnnounceOpts()
-    if (cbopts.uploaded) opts.uploaded = cbopts.uploaded
-    if (cbopts.downloaded) opts.downloaded = cbopts.downloaded
-    if (cbopts.left) opts.left = cbopts.left
-  }
-
   self._generateOffers(numwant, function (offers) {
-    var params = {
+    var params = extend(opts, {
       numwant: numwant,
-      uploaded: opts.uploaded || 0,
-      downloaded: opts.downloaded,
-      left: opts.left,
-      event: opts.event,
       info_hash: self.client._infoHashBinary,
       peer_id: self.client._peerIdBinary,
-      offers: offers,
-      extras: cbopts && cbopts.extraAnnounceOpts
-    }
+      offers: offers
+    })
     if (self._trackerId) params.trackerid = self._trackerId
 
     self._send(params)