diff --git a/src/VectorConferenceHandler.js b/src/VectorConferenceHandler.js
index c53a01d464..e839d3f78b 100644
--- a/src/VectorConferenceHandler.js
+++ b/src/VectorConferenceHandler.js
@@ -17,9 +17,9 @@ limitations under the License.
 "use strict";
 
 import Promise from 'bluebird';
-var Matrix = require("matrix-js-sdk");
-var Room = Matrix.Room;
-var CallHandler = require('./CallHandler');
+const Matrix = require("matrix-js-sdk");
+const Room = Matrix.Room;
+const CallHandler = require('./CallHandler');
 
 // FIXME: this is Riot (Vector) specific code, but will be removed shortly when
 // we switch over to jitsi entirely for video conferencing.
@@ -28,8 +28,8 @@ var CallHandler = require('./CallHandler');
 // This is bad because it prevents people running their own ASes from being used.
 // This isn't permanent and will be customisable in the future: see the proposal
 // at docs/conferencing.md for more info.
-var USER_PREFIX = "fs_";
-var DOMAIN = "matrix.org";
+const USER_PREFIX = "fs_";
+const DOMAIN = "matrix.org";
 
 function ConferenceCall(matrixClient, groupChatRoomId) {
     this.client = matrixClient;
@@ -38,14 +38,14 @@ function ConferenceCall(matrixClient, groupChatRoomId) {
 }
 
 ConferenceCall.prototype.setup = function() {
-    var self = this;
+    const self = this;
     return this._joinConferenceUser().then(function() {
         return self._getConferenceUserRoom();
     }).then(function(room) {
         // return a call for *this* room to be placed. We also tack on
         // confUserId to speed up lookups (else we'd need to loop every room
         // looking for a 1:1 room with this conf user ID!)
-        var call = Matrix.createNewMatrixCall(self.client, room.roomId);
+        const call = Matrix.createNewMatrixCall(self.client, room.roomId);
         call.confUserId = self.confUserId;
         call.groupRoomId = self.groupRoomId;
         return call;
@@ -54,11 +54,11 @@ ConferenceCall.prototype.setup = function() {
 
 ConferenceCall.prototype._joinConferenceUser = function() {
     // Make sure the conference user is in the group chat room
-    var groupRoom = this.client.getRoom(this.groupRoomId);
+    const groupRoom = this.client.getRoom(this.groupRoomId);
     if (!groupRoom) {
         return Promise.reject("Bad group room ID");
     }
-    var member = groupRoom.getMember(this.confUserId);
+    const member = groupRoom.getMember(this.confUserId);
     if (member && member.membership === "join") {
         return Promise.resolve();
     }
@@ -67,10 +67,10 @@ ConferenceCall.prototype._joinConferenceUser = function() {
 
 ConferenceCall.prototype._getConferenceUserRoom = function() {
     // Use an existing 1:1 with the conference user; else make one
-    var rooms = this.client.getRooms();
-    var confRoom = null;
-    for (var i = 0; i < rooms.length; i++) {
-        var confUser = rooms[i].getMember(this.confUserId);
+    const rooms = this.client.getRooms();
+    let confRoom = null;
+    for (let i = 0; i < rooms.length; i++) {
+        const confUser = rooms[i].getMember(this.confUserId);
         if (confUser && confUser.membership === "join" &&
                 rooms[i].getJoinedMemberCount() === 2) {
             confRoom = rooms[i];
@@ -82,7 +82,7 @@ ConferenceCall.prototype._getConferenceUserRoom = function() {
     }
     return this.client.createRoom({
         preset: "private_chat",
-        invite: [this.confUserId]
+        invite: [this.confUserId],
     }).then(function(res) {
         return new Room(res.room_id, null, client.getUserId());
     });
@@ -97,9 +97,9 @@ module.exports.isConferenceUser = function(userId) {
     if (userId.indexOf("@" + USER_PREFIX) !== 0) {
         return false;
     }
-    var base64part = userId.split(":")[0].substring(1 + USER_PREFIX.length);
+    const base64part = userId.split(":")[0].substring(1 + USER_PREFIX.length);
     if (base64part) {
-        var decoded = new Buffer(base64part, "base64").toString();
+        const decoded = new Buffer(base64part, "base64").toString();
         // ! $STUFF : $STUFF
         return /^!.+:.+/.test(decoded);
     }
@@ -108,23 +108,23 @@ module.exports.isConferenceUser = function(userId) {
 
 module.exports.getConferenceUserIdForRoom = function(roomId) {
     // abuse browserify's core node Buffer support (strip padding ='s)
-    var base64RoomId = new Buffer(roomId).toString("base64").replace(/=/g, "");
+    const base64RoomId = new Buffer(roomId).toString("base64").replace(/=/g, "");
     return "@" + USER_PREFIX + base64RoomId + ":" + DOMAIN;
 };
 
 module.exports.createNewMatrixCall = function(client, roomId) {
-    var confCall = new ConferenceCall(
-        client, roomId
+    const confCall = new ConferenceCall(
+        client, roomId,
     );
     return confCall.setup();
 };
 
 module.exports.getConferenceCallForRoom = function(roomId) {
     // search for a conference 1:1 call for this group chat room ID
-    var activeCall = CallHandler.getAnyActiveCall();
+    const activeCall = CallHandler.getAnyActiveCall();
     if (activeCall && activeCall.confUserId) {
-        var thisRoomConfUserId = module.exports.getConferenceUserIdForRoom(
-            roomId
+        const thisRoomConfUserId = module.exports.getConferenceUserIdForRoom(
+            roomId,
         );
         if (thisRoomConfUserId === activeCall.confUserId) {
             return activeCall;