diff --git a/activitypub.py b/activitypub.py
index b413c022..4eb56249 100644
--- a/activitypub.py
+++ b/activitypub.py
@@ -1,4 +1,3 @@
-# coding=utf-8
 """Handles requests for ActivityPub endpoints: actors, inbox, etc.
 """
 import json
@@ -14,21 +13,25 @@ import requests
 import webapp2
 from webmentiontools import send
 
+import common
+
 
 # https://www.w3.org/TR/activitypub/#retrieving-objects
-CONTENT_TYPE = 'application/ld+json; profile="https://www.w3.org/ns/activitystreams"'
-USER_AGENT = 'bridgy-federated (https://fed.brid.gy/)'
+CONTENT_TYPE_AS2 = 'application/ld+json; profile="https://www.w3.org/ns/activitystreams"'
+CONTENT_TYPE_AS = 'application/activity+json'
+CONNEG_HEADER = {
+    'Accept': '%s; q=0.9, %s; q=0.8' % (CONTENT_TYPE_AS2, CONTENT_TYPE_AS),
+}
+
 DOMAIN_RE = r'([^/]+\.[^/]+)'
 
+
 class ActorHandler(webapp2.RequestHandler):
     """Serves /[DOMAIN], fetches its mf2, converts to AS Actor, and serves it."""
 
     def get(self, domain):
         url = 'https://%s/' % domain
-        resp = requests.get(url=url, headers={
-            'User-Agent': USER_AGENT,
-        })
-        resp.raise_for_status()
+        resp = common.requests_get(url)
         mf2 = mf2py.parse(resp.text, url=resp.url)
         logging.info('Parsed mf2 for %s: %s', resp.url, json.dumps(mf2, indent=2))
 
@@ -42,7 +45,7 @@ class ActorHandler(webapp2.RequestHandler):
         logging.info('Returning: %s', json.dumps(obj, indent=2))
 
         self.response.headers.update({
-            'Content-Type': CONTENT_TYPE,
+            'Content-Type': CONTENT_TYPE_AS2,
             'Access-Control-Allow-Origin': '*',
         })
         self.response.write(json.dumps(obj, indent=2))
@@ -73,7 +76,7 @@ class InboxHandler(webapp2.RequestHandler):
         for target in targets:
             logging.info('Sending webmention from %s to %s', source, target)
             wm = send.WebmentionSend(source, target)
-            if wm.send(headers={'User-Agent': USER_AGENT}):
+            if wm.send(headers=common.HEADERS):
                 logging.info('Success: %s', wm.response)
             else:
                 logging.warning('Failed: %s', wm.error)
diff --git a/app.yaml b/app.yaml
index 6f168639..906b55c2 100644
--- a/app.yaml
+++ b/app.yaml
@@ -35,9 +35,14 @@ handlers:
   upload: static/index.html
 
 # dynamic
-- url: /[^/]+/?
+- url: /[^/]+/?(inbox)?
   script: activitypub.app
-  secure: always
+  # TODO
+  # secure: always
+
+- url: /webmention
+  script: webmention.app
+  # secure: always
 
 skip_files:
 - ^(.*/)?.*\.py[co]
diff --git a/common.py b/common.py
new file mode 100644
index 00000000..d8b44d2d
--- /dev/null
+++ b/common.py
@@ -0,0 +1,33 @@
+"""Misc common utilities.
+"""
+import json
+import logging
+
+import mf2py
+import requests
+
+HEADERS = {
+    'User-Agent': 'bridgy-federated (https://fed.brid.gy/)',
+}
+
+
+def requests_get(url, **kwargs):
+    kwargs.setdefault('headers', {}).update(HEADERS)
+    resp = requests.get(url, **kwargs)
+    resp.raise_for_status()
+    return resp
+
+
+# def fetch_mf2(url):
+#     """Fetches a URL and parses and returns its mf2.
+
+#     Args:
+#       url: string
+
+#     Returns: dict, parsed mf2
+#     """
+#     resp = requests.get(url=url, headers={'User-Agent': USER_AGENT})
+#     resp.raise_for_status()
+#     mf2 = mf2py.parse(resp.text, url=resp.url)
+#     logging.info('Parsed mf2 for %s: %s', resp.url, json.dumps(mf2, indent=2))
+#     return mf2
diff --git a/test/test_activitypub.py b/test/test_activitypub.py
index b77ecc99..67846315 100644
--- a/test/test_activitypub.py
+++ b/test/test_activitypub.py
@@ -12,6 +12,7 @@ import requests
 
 import activitypub
 from activitypub import app
+import common
 
 
 @mock.patch('requests.post')
@@ -34,7 +35,7 @@ class ActivityPubTest(unittest.TestCase):
 
         got = app.get_response('/foo.com')
         self.assertEquals(200, got.status_int)
-        self.assertEquals(activitypub.CONTENT_TYPE, got.headers['Content-Type'])
+        self.assertEquals(activitypub.CONTENT_TYPE_AS2, got.headers['Content-Type'])
         self.assertEquals({
             'objectType' : 'person',
             'displayName': u'Mrs. ☕ Foo',
@@ -73,5 +74,5 @@ class ActivityPubTest(unittest.TestCase):
                 'target': 'http://orig/post',
             },
             allow_redirects=False,
-            headers={'User-Agent': activitypub.USER_AGENT},
+            headers=common.HEADERS,
             verify=False)