diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 77e0975..122e4f5 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -10,8 +10,9 @@ test:
   stage: test
   script:
   - pip3 install -r requirements.txt
-  - sudo -u matemat python3 -m coverage run --branch -m unittest discover matemat
-  - sudo -u matemat python3 -m coverage report -m --include 'matemat/*' --omit '*/test_*.py' --omit 'matemat/webserver/test/abstract_httpd_test.py'
+  - sudo -u matemat python3 -m coverage run --rcfile=setup.cfg -m unittest discover matemat
+  - sudo -u matemat python3 -m coverage combine
+  - sudo -u matemat python3 -m coverage report --rcfile=setup.cfg
 
 codestyle:
   stage: test
diff --git a/matemat/webserver/httpd.py b/matemat/webserver/httpd.py
index 24916be..c0a351d 100644
--- a/matemat/webserver/httpd.py
+++ b/matemat/webserver/httpd.py
@@ -1,8 +1,7 @@
 
-from typing import Any, Callable, Dict, List, Tuple, Type, Union
+from typing import Any, Callable, Dict, Set, Tuple, Type, Union
 
 import logging
-import sys
 import os
 import socket
 import mimetypes
@@ -40,7 +39,7 @@ _PAGELET_PATHS: Dict[str, Callable[[str,  # HTTP method (GET, POST, ...)
                                        PageletResponse,  # A generic response
                                    ]]] = dict()
 # The pagelet initialization functions, to be executed upon startup
-_PAGELET_INIT_FUNCTIONS: List[Callable[[Dict[str, str], logging.Logger], None]] = []
+_PAGELET_INIT_FUNCTIONS: Set[Callable[[Dict[str, str], logging.Logger], None]] = set()
 
 # Inactivity timeout for client sessions
 _SESSION_TIMEOUT: int = 3600
@@ -116,7 +115,7 @@ def pagelet_init(fun: Callable[[Dict[str, str], logging.Logger], None]):
 
     :param fun: The function to annotate
     """
-    _PAGELET_INIT_FUNCTIONS.append(fun)
+    _PAGELET_INIT_FUNCTIONS.add(fun)
 
 
 class MatematHTTPServer(HTTPServer):
@@ -221,7 +220,7 @@ class MatematWebserver(object):
             # If an error occurs, log it and terminate
             self._httpd.logger.exception(e)
             self._httpd.logger.critical('An initialization pagelet raised an error.  Stopping.')
-            sys.exit(1)
+            raise e
         # If pagelet initialization went fine, start the HTTP server
         self._httpd.serve_forever()
 
diff --git a/matemat/webserver/test/test_pagelet_init.py b/matemat/webserver/test/test_pagelet_init.py
new file mode 100644
index 0000000..21c30e4
--- /dev/null
+++ b/matemat/webserver/test/test_pagelet_init.py
@@ -0,0 +1,63 @@
+from typing import Any, Dict
+
+import unittest
+import http.client
+
+import logging
+import threading
+
+from matemat.webserver import MatematWebserver, RequestArguments, pagelet_init, pagelet
+
+
+@pagelet('/just/testing/init')
+def init_test_pagelet(method: str,
+                      path: str,
+                      args: RequestArguments,
+                      session_vars: Dict[str, Any],
+                      headers: Dict[str, str],
+                      pagelet_variables: Dict[str, str]):
+    return pagelet_variables['Unit-Test']
+
+
+_INIT_FAIL = False
+
+
+@pagelet_init
+def init(config: Dict[str, str],
+         logger: logging.Logger):
+    if _INIT_FAIL:
+        raise ValueError('This error should be raised!')
+    config['Unit-Test'] = 'Pagelet Init Test'
+
+
+class TestPageletInitialization(unittest.TestCase):
+
+    def tearDown(self):
+        global _INIT_FAIL
+        _INIT_FAIL = False
+
+    def test_pagelet_init_ok(self):
+        """
+        Test successful pagelet initialization
+        """
+        srv = MatematWebserver('::1', 0, '/nonexistent', '/nonexistent', {}, {}, logging.NOTSET, logging.NullHandler())
+        port = int(srv._httpd.socket.getsockname()[1])
+        thread = threading.Thread(target=srv.start)
+        thread.start()
+        con = http.client.HTTPConnection(f'[::1]:{port}')
+        con.request('GET', '/just/testing/init')
+        response = con.getresponse().read()
+        srv._httpd.shutdown()
+        srv._httpd.socket.close()
+        self.assertEqual(b'Pagelet Init Test', response)
+
+    def test_pagelet_init_fail(self):
+        """
+        Test unsuccessful pagelet initialization
+        """
+        global _INIT_FAIL
+        _INIT_FAIL = True
+        srv = MatematWebserver('::1', 0, '/nonexistent', '/nonexistent', {}, {}, logging.NOTSET, logging.NullHandler())
+        with self.assertRaises(ValueError):
+            srv.start()
+        srv._httpd.socket.close()
diff --git a/setup.cfg b/setup.cfg
index 62acd3a..2dcea66 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,3 +1,22 @@
+
+#
+# PyCodestyle
+#
+
 [pycodestyle]
 max-line-length = 120
 statistics = True
+
+#
+# Coverage
+#
+
+[run]
+branch = True
+parallel = True
+source = matemat/
+
+[report]
+show_missing = True
+include = matemat/*
+omit = */test/*.py