diff --git a/src/wormhole/server/rendezvous.py b/src/wormhole/server/rendezvous.py
index acb76c1..dc3ebaa 100644
--- a/src/wormhole/server/rendezvous.py
+++ b/src/wormhole/server/rendezvous.py
@@ -1,14 +1,8 @@
 from __future__ import print_function, unicode_literals
-import os, time, random, base64, json
+import os, random, base64
 from collections import namedtuple
 from twisted.python import log
-from twisted.application import service, internet
-
-SECONDS = 1.0
-MINUTE = 60*SECONDS
-
-CHANNEL_EXPIRATION_TIME = 11*MINUTE
-EXPIRATION_CHECK_PERIOD = 10*MINUTE
+from twisted.application import service
 
 def generate_mailbox_id():
     return base64.b32encode(os.urandom(8)).lower().strip(b"=").decode("ascii")
@@ -478,17 +472,14 @@ class AppNamespace:
             channel._shutdown()
 
 class Rendezvous(service.MultiService):
-    def __init__(self, db, welcome, blur_usage, stats_file=None):
+    def __init__(self, db, welcome, blur_usage):
         service.MultiService.__init__(self)
         self._db = db
         self._welcome = welcome
         self._blur_usage = blur_usage
-        self._stats_file = stats_file
         log_requests = blur_usage is None
         self._log_requests = log_requests
         self._apps = {}
-        t = internet.TimerService(EXPIRATION_CHECK_PERIOD, self.timer)
-        t.setServiceParent(self)
 
     def get_welcome(self):
         return self._welcome
@@ -518,34 +509,19 @@ class Rendezvous(service.MultiService):
             apps.add(row["app_id"])
         return apps
 
-    def timer(self):
-        self.prune_all_apps()
-        self.dump_stats(now=time.time(), validity=EXPIRATION_CHECK_PERIOD+60)
-
-    def prune_all_apps(self, now=None, old=None):
+    def prune_all_apps(self, now, old):
         # As with AppNamespace.prune_old_mailboxes, we log for now.
         log.msg("beginning app prune")
-        now = now or time.time()
-        old = old or (now - CHANNEL_EXPIRATION_TIME)
         for app_id in sorted(self.get_all_apps()):
             log.msg(" app prune checking %r" % (app_id,))
             app = self.get_app(app_id)
             app.prune(now, old)
         log.msg("app prune ends, %d apps" % len(self._apps))
 
-    def dump_stats(self, now, validity):
-        if not self._stats_file:
-            return
-        tmpfn = self._stats_file + ".tmp"
+    def get_stats(self):
+        stats = {}
 
-        data = {}
-        data["created"] = now
-        data["valid_until"] = now + validity
-
-        with open(tmpfn, "wb") as f:
-            json.dump(data, f, indent=1)
-            f.write("\n")
-        os.rename(tmpfn, self._stats_file)
+        return stats
 
     def stopService(self):
         # This forcibly boots any clients that are still connected, which
diff --git a/src/wormhole/server/server.py b/src/wormhole/server/server.py
index b7b9f2a..443e75e 100644
--- a/src/wormhole/server/server.py
+++ b/src/wormhole/server/server.py
@@ -1,9 +1,10 @@
 # NO unicode_literals or static.Data() will break, because it demands
 # a str on Python 2
 from __future__ import print_function
+import os, time, json
 from twisted.python import log
 from twisted.internet import reactor, endpoints
-from twisted.application import service
+from twisted.application import service, internet
 from twisted.web import server, static, resource
 from autobahn.twisted.resource import WebSocketResource
 from .endpoint_service import ServerEndpointService
@@ -13,6 +14,12 @@ from .rendezvous import Rendezvous
 from .rendezvous_websocket import WebSocketRendezvousFactory
 from .transit_server import Transit
 
+SECONDS = 1.0
+MINUTE = 60*SECONDS
+
+CHANNEL_EXPIRATION_TIME = 11*MINUTE
+EXPIRATION_CHECK_PERIOD = 10*MINUTE
+
 class Root(resource.Resource):
     # child_FOO is a nevow thing, not a twisted.web.resource thing
     def __init__(self):
@@ -52,11 +59,11 @@ class RelayServer(service.MultiService):
         if signal_error:
             welcome["error"] = signal_error
 
-        rendezvous = Rendezvous(db, welcome, blur_usage, stats_file)
-        rendezvous.setServiceParent(self) # for the pruning timer
+        self._rendezvous = Rendezvous(db, welcome, blur_usage)
+        self._rendezvous.setServiceParent(self) # for the pruning timer
 
         root = Root()
-        wsrf = WebSocketRendezvousFactory(None, rendezvous)
+        wsrf = WebSocketRendezvousFactory(None, self._rendezvous)
         root.putChild(b"v1", WebSocketResource(wsrf))
 
         site = PrivacyEnhancedSite(root)
@@ -74,9 +81,12 @@ class RelayServer(service.MultiService):
             transit_service = ServerEndpointService(t, transit)
             transit_service.setServiceParent(self)
 
+        self._stats_file = stats_file
+        t = internet.TimerService(EXPIRATION_CHECK_PERIOD, self.timer)
+        t.setServiceParent(self)
+
         # make some things accessible for tests
         self._db = db
-        self._rendezvous = rendezvous
         self._root = root
         self._rendezvous_web_service = rendezvous_web_service
         self._rendezvous_websocket = wsrf
@@ -93,3 +103,25 @@ class RelayServer(service.MultiService):
             log.msg("not logging HTTP requests")
         else:
             log.msg("not blurring access times")
+
+    def timer(self):
+        now = time.time()
+        old = now - CHANNEL_EXPIRATION_TIME
+        self._rendezvous.prune_all_apps(now, old)
+        self.dump_stats(now, validity=EXPIRATION_CHECK_PERIOD+60)
+
+    def dump_stats(self, now, validity):
+        if not self._stats_file:
+            return
+        tmpfn = self._stats_file + ".tmp"
+
+        data = {}
+        data["created"] = now
+        data["valid_until"] = now + validity
+
+        data["rendezvous"] = self._rendezvous.get_stats()
+
+        with open(tmpfn, "wb") as f:
+            json.dump(data, f, indent=1)
+            f.write("\n")
+        os.rename(tmpfn, self._stats_file)