diff --git a/matrix_alertbot/alertmanager.py b/matrix_alertbot/alertmanager.py
index bab8a0c..1bdc7c4 100644
--- a/matrix_alertbot/alertmanager.py
+++ b/matrix_alertbot/alertmanager.py
@@ -1,7 +1,7 @@
 import datetime
 from typing import Dict, List
 
-import diskcache
+from diskcache import Cache
 import pytimeparse
 import requests
 from requests import RequestException
@@ -15,10 +15,9 @@ from matrix_alertbot.errors import (
 
 
 class AlertmanagerClient:
-    def __init__(self, config: Config) -> None:
-        url = config.alertmanager_url
+    def __init__(self, url: str, cache: Cache) -> None:
         self.api_url = f"{url}/api/v2"
-        self.cache = diskcache.Cache(config.cache_dir)
+        self.cache = cache
 
     def get_alerts(self) -> List[Dict]:
         try:
diff --git a/matrix_alertbot/callbacks.py b/matrix_alertbot/callbacks.py
index 8f82d52..0833726 100644
--- a/matrix_alertbot/callbacks.py
+++ b/matrix_alertbot/callbacks.py
@@ -25,6 +25,7 @@ class Callbacks:
         self,
         client: AsyncClient,
         alertmanager: AlertmanagerClient,
+        cache: Cache,
         config: Config,
     ):
         """
@@ -38,7 +39,7 @@ class Callbacks:
             config: Bot configuration parameters.
         """
         self.client = client
-        self.cache = Cache(config.cache_dir)
+        self.cache = cache
         self.alertmanager = alertmanager
         self.config = config
         self.command_prefix = config.command_prefix
diff --git a/matrix_alertbot/main.py b/matrix_alertbot/main.py
index 920fc97..8092b7d 100644
--- a/matrix_alertbot/main.py
+++ b/matrix_alertbot/main.py
@@ -88,8 +88,11 @@ def main() -> None:
     # Read the parsed config file and create a Config object
     config = Config(config_path)
 
+    # Configure the cache
+    cache = diskcache.Cache(config.cache_dir)
+
     # Configure Alertmanager client
-    alertmanager = AlertmanagerClient(config)
+    alertmanager = AlertmanagerClient(config.alertmanager_url, cache)
 
     # Configuration options for the AsyncClient
     client_config = AsyncClientConfig(
@@ -113,7 +116,7 @@ def main() -> None:
         client.user_id = config.user_id
 
     # Set up event callbacks
-    callbacks = Callbacks(client, alertmanager, config)
+    callbacks = Callbacks(client, alertmanager, cache, config)
     client.add_event_callback(callbacks.message, (RoomMessageText,))
     client.add_event_callback(
         callbacks.invite_event_filtered_callback, (InviteMemberEvent,)
@@ -121,7 +124,7 @@ def main() -> None:
     client.add_event_callback(callbacks.decryption_failure, (MegolmEvent,))
     client.add_event_callback(callbacks.unknown, (UnknownEvent,))
 
-    webhook_server = Webhook(client, config)
+    webhook_server = Webhook(client, cache, config)
 
     loop = asyncio.get_event_loop()
     loop.create_task(webhook_server.start())
diff --git a/matrix_alertbot/webhook.py b/matrix_alertbot/webhook.py
index fd81788..80b45c3 100644
--- a/matrix_alertbot/webhook.py
+++ b/matrix_alertbot/webhook.py
@@ -48,9 +48,7 @@ async def create_alert(request: web_request.Request) -> web.Response:
 
 
 class Webhook:
-    def __init__(self, client: AsyncClient, config: Config) -> None:
-        cache = Cache(config.cache_dir)
-
+    def __init__(self, client: AsyncClient, cache: Cache, config: Config) -> None:
         self.app = web.Application(logger=logger)
         self.app["client"] = client
         self.app["config"] = config
diff --git a/tests/test_callbacks.py b/tests/test_callbacks.py
index 41e6733..4c1fa11 100644
--- a/tests/test_callbacks.py
+++ b/tests/test_callbacks.py
@@ -2,6 +2,7 @@ import unittest
 from unittest.mock import Mock
 
 import nio
+from diskcache import Cache
 
 from matrix_alertbot.alertmanager import AlertmanagerClient
 from matrix_alertbot.callbacks import Callbacks
@@ -15,13 +16,14 @@ class CallbacksTestCase(unittest.TestCase):
         self.fake_client = Mock(spec=nio.AsyncClient)
         self.fake_client.user = "@fake_user:example.com"
 
+        self.fake_cache = Mock(spec=Cache)
         self.fake_alertmanager = Mock(spec=AlertmanagerClient)
 
         # We don't spec config, as it doesn't currently have well defined attributes
         self.fake_config = Mock()
 
         self.callbacks = Callbacks(
-            self.fake_client, self.fake_alertmanager, self.fake_config
+            self.fake_client, self.fake_cache, self.fake_alertmanager, self.fake_config
         )
 
     def test_invite(self) -> None: