diff --git a/firecrestspawner/api.py b/firecrestspawner/api.py
index f3441db..61f6a37 100644
--- a/firecrestspawner/api.py
+++ b/firecrestspawner/api.py
@@ -26,7 +26,7 @@ def post(self):
             if hasattr(spawner, key):
                 setattr(spawner, key, value)
 
-        self.finish(json.dumps({"message": "BatchSpawner data configured"}))
+        self.finish(json.dumps({"message": "FirecRESTSpawner data configured"}))
         self.set_status(201)
 
 
diff --git a/firecrestspawner/singleuser.py b/firecrestspawner/singleuser.py
index 37f1dcb..298d60e 100644
--- a/firecrestspawner/singleuser.py
+++ b/firecrestspawner/singleuser.py
@@ -1,28 +1,27 @@
 import os
 import sys
-import requests
-
 from runpy import run_path
 from shutil import which
+from urllib.parse import urlparse
 
-from jupyterhub.utils import random_port, url_path_join
+import requests
 from jupyterhub.services.auth import HubAuth
+from jupyterhub.utils import url_path_join
 
 
 def main(argv=None):
-    port = random_port()
+    url = urlparse(os.environ["JUPYTERHUB_SERVICE_URL"])
+    port = url.port
     hub_auth = HubAuth()
-    hub_auth.client_ca = os.environ.get('JUPYTERHUB_SSL_CLIENT_CA', '')
-    hub_auth.certfile = os.environ.get('JUPYTERHUB_SSL_CERTFILE', '')
-    hub_auth.keyfile = os.environ.get('JUPYTERHUB_SSL_KEYFILE', '')
     requests.post(
-        url=url_path_join(hub_auth.api_url, 'firecrestspawner'),
-        headers = {"Authorization": f"token {hub_auth.api_token}"},
+        url=url_path_join(hub_auth.api_url, "firecrestspawner"),
+        headers={"Authorization": f"token {hub_auth.api_token}"},
         json={"port": port},
     )
     cmd_path = which(sys.argv[1])
-    sys.argv = sys.argv[1:] + ['--port={}'.format(port)]
+    sys.argv = sys.argv[1:] + ["--port={}".format(port)]
     run_path(cmd_path, run_name="__main__")
 
+
 if __name__ == "__main__":
     main()
diff --git a/firecrestspawner/spawner.py b/firecrestspawner/spawner.py
index ebb0add..8939487 100644
--- a/firecrestspawner/spawner.py
+++ b/firecrestspawner/spawner.py
@@ -15,7 +15,7 @@
 import firecrest as f7t
 from enum import Enum
 from jinja2 import Template
-from tornado import gen
+# from tornado import gen
 from jupyterhub.spawner import Spawner
 from traitlets import (
     Any, Integer, Unicode, Float, default
@@ -341,7 +341,7 @@ async def start(self):
         if self.port == 0:
             self.port = self.traits()['port'].default_value
 
-        if jupyterhub.version_info >= (0, 8) and self.server:
+        if self.server:
             self.server.port = self.port
 
         await self.submit_batch_script()
@@ -369,20 +369,10 @@ async def start(self):
                 raise RuntimeError('The Jupyter batch job has disappeared'
                                    ' while pending in the queue or died '
                                    ' immediately after starting.')
-            await gen.sleep(self.startup_poll_interval)
+            await asyncio.sleep(self.startup_poll_interval)
 
         self.ip = await self.state_gethost()
-        while self.port == 0:
-            await gen.sleep(self.startup_poll_interval)
-            # Test framework: For testing, mock_port is set because we
-            # don't actually run the single-user server yet.
-            if hasattr(self, 'mock_port'):
-                self.port = self.mock_port
-
-        if jupyterhub.version_info < (0, 7):
-            # store on user for pre-jupyterhub-0.7:
-            self.user.server.port = self.port
-            self.user.server.ip = self.ip
+
         self.db.commit()
         self.log.info(f"Notebook server job {self.job_id} started at "
                       f"{self.ip}:{self.port}")
@@ -403,7 +393,7 @@ async def stop(self, now=False):
             status = await self.query_job_status()
             if status not in (JobStatus.RUNNING, JobStatus.UNKNOWN):
                 return
-            await gen.sleep(1.0)
+            await asyncio.sleep(1.0)
         if self.job_id:
             self.log.warning(
                 f"Notebook server job {self.job_id} at {self.ip}:{self.port} "
@@ -426,7 +416,7 @@ async def progress(self):
                 await yield_({
                     "message": "Unknown status...",
                 })
-            await gen.sleep(1)
+            await asyncio.sleep(1)
 
 
 class FirecRESTSpawnerRegexStates(FirecRESTSpawnerBase):