diff --git a/tests/base.py b/tests/base.py
index 19bae11118..8ca571d070 100644
--- a/tests/base.py
+++ b/tests/base.py
@@ -14,6 +14,7 @@
 # under the License.
 
 import configparser
+from configparser import ConfigParser
 from contextlib import contextmanager
 import copy
 import datetime
@@ -28,6 +29,8 @@ import os
 import queue
 import random
 import re
+from logging import Logger
+
 import requests
 import select
 import shutil
@@ -58,6 +61,7 @@ import testtools.content_type
 from git.exc import NoSuchPathError
 import yaml
 import paramiko
+from zuul.lib.connections import ConnectionRegistry
 
 import tests.fakegithub
 import zuul.driver.gerrit.gerritsource as gerritsource
@@ -3410,6 +3414,61 @@ class SymLink(object):
         self.target = target
 
 
+class SchedulerTestApp:
+    def __init__(self, log: Logger, config: ConfigParser, zk_config: str,
+                 connections: ConnectionRegistry):
+        self.log = log
+        self.config = config
+        self.zk_config = zk_config
+
+        self.sched = zuul.scheduler.Scheduler(self.config)
+        self.sched.setZuulApp(self)
+        self.sched._stats_interval = 1
+
+        self.event_queues = [
+            self.sched.result_event_queue,
+            self.sched.trigger_event_queue,
+            self.sched.management_event_queue
+        ]
+
+        self.sched.registerConnections(connections)
+
+        self.executor_client = zuul.executor.client.ExecutorClient(
+            self.config, self.sched)
+        self.merge_client = RecordingMergeClient(self.config, self.sched)
+        self.nodepool = zuul.nodepool.Nodepool(self.sched)
+        self.zk = zuul.zk.ZooKeeper(enable_cache=True)
+        self.zk.connect(self.zk_config, timeout=30.0)
+
+        self.sched.setExecutor(self.executor_client)
+        self.sched.setMerger(self.merge_client)
+        self.sched.setNodepool(self.nodepool)
+        self.sched.setZooKeeper(self.zk)
+
+        self.sched.start()
+        self.executor_client.gearman.waitForServer()
+        self.sched.reconfigure(self.config)
+        self.sched.resume()
+
+    def fullReconfigure(self):
+        try:
+            self.sched.reconfigure(self.config)
+        except Exception:
+            self.log.exception("Reconfiguration failed:")
+
+    def smartReconfigure(self, command_socket=False):
+        try:
+            if command_socket:
+                command_socket = self.config.get('scheduler', 'command_socket')
+                with socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) as s:
+                    s.connect(command_socket)
+                    s.sendall('smart-reconfigure\n'.encode('utf8'))
+            else:
+                self.sched.reconfigure(self.config, smart=True)
+        except Exception:
+            self.log.exception("Reconfiguration failed:")
+
+
 class ZuulTestCase(BaseTestCase):
     """A test case with a functioning Zuul.
 
@@ -3487,6 +3546,10 @@ class ZuulTestCase(BaseTestCase):
         super(ZuulTestCase, self).setUp()
 
         self.setupZK()
+        self.fake_nodepool = FakeNodepool(
+            self.zk_chroot_fixture.zookeeper_host,
+            self.zk_chroot_fixture.zookeeper_port,
+            self.zk_chroot_fixture.zookeeper_chroot)
 
         if not KEEP_TEMPDIRS:
             tmp_root = self.useFixture(fixtures.TempDir(
@@ -3579,23 +3642,9 @@ class ZuulTestCase(BaseTestCase):
         gerritsource.GerritSource.replication_retry_interval = 0.5
         gerritconnection.GerritEventConnector.delay = 0.0
 
-        self.sched = zuul.scheduler.Scheduler(self.config)
-        self.sched.setZuulApp(self)
-        self.sched._stats_interval = 1
-
-        self.event_queues = [
-            self.sched.result_event_queue,
-            self.sched.trigger_event_queue,
-            self.sched.management_event_queue
-        ]
+        self.event_queues = []
         self.poller_events = {}
-
         self.configure_connections()
-        self.sched.registerConnections(self.connections)
-
-        if hasattr(self, 'fake_github'):
-            self.event_queues.append(
-                self.fake_github.github_event_connector._event_forward_queue)
 
         self.executor_server = RecordingExecutorServer(
             self.config, self.connections,
@@ -3608,52 +3657,27 @@ class ZuulTestCase(BaseTestCase):
         self.history = self.executor_server.build_history
         self.builds = self.executor_server.running_builds
 
-        self.executor_client = zuul.executor.client.ExecutorClient(
-            self.config, self.sched)
-        self.merge_client = RecordingMergeClient(self.config, self.sched)
+        self.sched_app = SchedulerTestApp(self.log, self.config,
+                                          self.zk_config,
+                                          self.connections)
+        self.sched = self.sched_app.sched
+        self.event_queues = self.sched_app.event_queues + self.event_queues
+
+        if hasattr(self, 'fake_github'):
+            self.event_queues.append(
+                self.fake_github.github_event_connector._event_forward_queue)
+
+        self.executor_client = self.sched_app.executor_client
+        self.merge_client = self.sched_app.merge_client
         self.merge_server = None
-        self.nodepool = zuul.nodepool.Nodepool(self.sched)
-        self.zk = zuul.zk.ZooKeeper(enable_cache=True)
-        self.zk.connect(self.zk_config, timeout=30.0)
+        self.nodepool = self.sched_app.nodepool
+        self.zk = self.sched_app.zk
 
-        self.fake_nodepool = FakeNodepool(
-            self.zk_chroot_fixture.zookeeper_host,
-            self.zk_chroot_fixture.zookeeper_port,
-            self.zk_chroot_fixture.zookeeper_chroot)
-
-        self.sched.setExecutor(self.executor_client)
-        self.sched.setMerger(self.merge_client)
-        self.sched.setNodepool(self.nodepool)
-        self.sched.setZooKeeper(self.zk)
-
-        self.sched.start()
-        self.executor_client.gearman.waitForServer()
         # Cleanups are run in reverse order
         self.addCleanup(self.assertCleanShutdown)
         self.addCleanup(self.shutdown)
         self.addCleanup(self.assertFinalState)
 
-        self.sched.reconfigure(self.config)
-        self.sched.resume()
-
-    def fullReconfigure(self):
-        try:
-            self.sched.reconfigure(self.config)
-        except Exception:
-            self.log.exception("Reconfiguration failed:")
-
-    def smartReconfigure(self, command_socket=False):
-        try:
-            if command_socket:
-                command_socket = self.config.get('scheduler', 'command_socket')
-                with socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) as s:
-                    s.connect(command_socket)
-                    s.sendall('smart-reconfigure\n'.encode('utf8'))
-            else:
-                self.sched.reconfigure(self.config, smart=True)
-        except Exception:
-            self.log.exception("Reconfiguration failed:")
-
     def configure_connections(self, source_only=False):
         # Set up gerrit related fakes
         # Set a changes database so multiple FakeGerrit's can report back to
diff --git a/tests/unit/test_scheduler.py b/tests/unit/test_scheduler.py
index bb4c949e58..f3b8718a49 100644
--- a/tests/unit/test_scheduler.py
+++ b/tests/unit/test_scheduler.py
@@ -8169,7 +8169,7 @@ class TestSchedulerSmartReconfiguration(ZuulTestCase):
 
         self.newTenantConfig('config/multi-tenant/main-reconfig.yaml')
 
-        self.smartReconfigure(command_socket=command_socket)
+        self.sched_app.smartReconfigure(command_socket=command_socket)
 
         # Wait for smart reconfiguration. Only tenant-two should be
         # reconfigured. Note that waitUntilSettled is not