diff --git a/server/src/uds/core/environment.py b/server/src/uds/core/environment.py
index 21fd46ced..65a1339a4 100644
--- a/server/src/uds/core/environment.py
+++ b/server/src/uds/core/environment.py
@@ -47,6 +47,7 @@ class Environment:
     not stored with main module data.
     The environment is composed of a "cache" and a "storage". First are volatile data, while second are persistent data.
     """
+    __slots__ = ['_key', '_cache', '_storage', '_idGenerators']
 
     _key: str
     _cache: Cache
@@ -173,6 +174,9 @@ class Environmentable:
     """
     This is a base class provided for all objects that have an environment associated. These are mainly modules
     """
+    __slots__ = ['_env']
+
+    _env: Environment
 
     def __init__(self, environment: Environment):
         """
diff --git a/server/src/uds/core/jobs/delayed_task.py b/server/src/uds/core/jobs/delayed_task.py
index c76d0cb65..aede4e313 100644
--- a/server/src/uds/core/jobs/delayed_task.py
+++ b/server/src/uds/core/jobs/delayed_task.py
@@ -42,6 +42,7 @@ class DelayedTask(Environmentable):
     This class represents a single delayed task object.
     This is an object that represents an execution to be done "later"
     """
+    __slots__ = ()
 
     def __init__(self):
         """
diff --git a/server/src/uds/core/jobs/delayed_task_runner.py b/server/src/uds/core/jobs/delayed_task_runner.py
index 9bf942adf..8e11769ee 100644
--- a/server/src/uds/core/jobs/delayed_task_runner.py
+++ b/server/src/uds/core/jobs/delayed_task_runner.py
@@ -44,6 +44,7 @@ from django.db.models import Q
 from uds.models import DelayedTask as DBDelayedTask
 from uds.models import getSqlDatetime
 from uds.core.environment import Environment
+from uds.core.util import singleton
 
 from .delayed_task import DelayedTask
 
@@ -54,6 +55,7 @@ class DelayedTaskThread(threading.Thread):
     """
     Class responsible of executing a delayed task in its own thread
     """
+    __slots__ = ('_taskInstance',)
 
     _taskInstance: DelayedTask
 
@@ -70,29 +72,27 @@ class DelayedTaskThread(threading.Thread):
             connections['default'].close()
 
 
-class DelayedTaskRunner:
+class DelayedTaskRunner(metaclass=singleton.Singleton):
     """
     Delayed task runner class
     """
+    __slots__ = ()
 
-    granularity: int = 2  # we check for delayed tasks every "granularity" seconds
-
-    # to keep singleton DelayedTaskRunner
-    _runner: typing.ClassVar[typing.Optional['DelayedTaskRunner']] = None
-    _hostname: str
-    _keepRunning: bool
+    granularity: typing.ClassVar[int] = 2  # we check for delayed tasks every "granularity" seconds
+    _hostname: typing.ClassVar[str]  # "Our" hostname
+    _keepRunning: typing.ClassVar[bool]  # If we should keep it running
 
     def __init__(self):
-        self._hostname = gethostname()
-        self._keepRunning = True
         logger.debug("Initializing delayed task runner for host %s", self._hostname)
+        DelayedTaskRunner._hostname = gethostname()
+        DelayedTaskRunner._keepRunning = True
 
     def notifyTermination(self) -> None:
         """
         Invoke this whenever you want to terminate the delayed task runner thread
         It will mark the thread to "stop" ASAP
         """
-        self._keepRunning = False
+        DelayedTaskRunner._keepRunning = False
 
     @staticmethod
     def runner() -> 'DelayedTaskRunner':
@@ -101,9 +101,7 @@ class DelayedTaskRunner:
         There is only one instance of DelayedTaksRunner, but its "run" method is executed on
         many thread (depending on configuration). They all share common Instance data
         """
-        if DelayedTaskRunner._runner is None:
-            DelayedTaskRunner._runner = DelayedTaskRunner()
-        return DelayedTaskRunner._runner
+        return DelayedTaskRunner()
 
     def executeOneDelayedTask(self) -> None:
         now = getSqlDatetime()
@@ -142,7 +140,7 @@ class DelayedTaskRunner:
             taskInstance.env = Environment.getEnvForType(taskInstance.__class__)
             DelayedTaskThread(taskInstance).start()
 
-    def __insert(self, instance: DelayedTask, delay: int, tag: str) -> None:
+    def _insert(self, instance: DelayedTask, delay: int, tag: str) -> None:
         now = getSqlDatetime()
         exec_time = now + timedelta(seconds=delay)
         cls = instance.__class__
@@ -170,7 +168,7 @@ class DelayedTaskRunner:
         while retries > 0:
             retries -= 1
             try:
-                self.__insert(instance, delay, tag)
+                self._insert(instance, delay, tag)
                 break
             except Exception as e:
                 logger.info('Exception inserting a delayed task %s: %s', e.__class__, e)
@@ -210,7 +208,7 @@ class DelayedTaskRunner:
 
     def run(self) -> None:
         logger.debug("At loop")
-        while self._keepRunning:
+        while DelayedTaskRunner._keepRunning:
             try:
                 time.sleep(self.granularity)
                 self.executeOneDelayedTask()
diff --git a/server/src/uds/core/jobs/job.py b/server/src/uds/core/jobs/job.py
index b1a40c34a..75f48d492 100644
--- a/server/src/uds/core/jobs/job.py
+++ b/server/src/uds/core/jobs/job.py
@@ -39,15 +39,16 @@ logger = logging.getLogger(__name__)
 
 
 class Job(Environmentable):
+    __slots__ = ('frequency',)
     # Default frecuency, once a day. Remenber that precision will be based on "granurality" of Scheduler
     # If a job is used for delayed execution, this attribute is in fact ignored
-    frecuency: int = (
+    frecuency: typing.ClassVar[int] = (
         24 * 3600 + 3
     )  # Defaults to a big one, and i know frecuency is written as frequency, but this is an "historical mistake" :)
-    frecuency_cfg: typing.Optional[
-        Config.Value
+    frecuency_cfg: typing.ClassVar[
+        typing.Optional[Config.Value]
     ] = None  # If we use a configuration variable from DB, we need to update the frecuency asap, but not before app is ready
-    friendly_name = 'Unknown'
+    friendly_name: typing.ClassVar[str] = 'Unknown'
 
     @classmethod
     def setup(cls: typing.Type['Job']) -> None:
diff --git a/server/src/uds/core/managers/task.py b/server/src/uds/core/managers/task.py
index 81d045b2a..7a6481602 100644
--- a/server/src/uds/core/managers/task.py
+++ b/server/src/uds/core/managers/task.py
@@ -68,10 +68,15 @@ class DelayedTaskThread(BaseThread):
 
 
 class TaskManager(metaclass=singleton.Singleton):
-    keepRunning: bool = True
-    threads: typing.List[BaseThread] = []
+
+    __slots__ = ('threads', 'keepRunning')
+
+    keepRunning: bool
+    threads: typing.List[BaseThread]
 
     def __init__(self):
+        self.keepRunning = True
+        self.threads = []
         pass
 
     @staticmethod
diff --git a/server/src/uds/core/module.py b/server/src/uds/core/module.py
index 2580b94a4..9bcc1cf82 100644
--- a/server/src/uds/core/module.py
+++ b/server/src/uds/core/module.py
@@ -97,6 +97,7 @@ class Module(UserInterface, Environmentable, Serializable):
     Environmentable is a base class that provides utility method to access a separate Environment for every single
     module.
     """
+    __slots__ = ['_uuid']
     # Import variable indicating this module is a base class not a real module
     # Note that Module is not a real module, but a base class for all modules so isBase is not used on this class
     isBase: typing.ClassVar[bool] = False
diff --git a/server/src/uds/core/serializable.py b/server/src/uds/core/serializable.py
index afcd464b5..9d8a9a477 100644
--- a/server/src/uds/core/serializable.py
+++ b/server/src/uds/core/serializable.py
@@ -43,6 +43,7 @@ class Serializable:
     - Initialize the object with default values
     - Read values from seralized data
     """
+    __slots__ = ()
 
     def __init__(self):
         pass
diff --git a/server/src/uds/core/util/calendar/__init__.py b/server/src/uds/core/util/calendar/__init__.py
index bfc36f7ce..6804df04b 100644
--- a/server/src/uds/core/util/calendar/__init__.py
+++ b/server/src/uds/core/util/calendar/__init__.py
@@ -53,14 +53,16 @@ ONE_DAY = 3600 * 24
 
 
 class CalendarChecker:
+    __slots__ = ('calendar',)
+    
     calendar: Calendar
 
     # For performance checking
-    updates: int = 0
-    cache_hit: int = 0
-    hits: int = 0
+    updates: typing.ClassVar[int] = 0
+    cache_hit: typing.ClassVar[int] = 0
+    hits: typing.ClassVar[int] = 0
 
-    cache = Cache('calChecker')
+    cache: typing.ClassVar[Cache] = Cache('calChecker')
 
     def __init__(self, calendar: Calendar) -> None:
         self.calendar = calendar
diff --git a/server/src/uds/core/util/middleware/redirect.py b/server/src/uds/core/util/middleware/redirect.py
index a5acb5641..db7d5fd6a 100644
--- a/server/src/uds/core/util/middleware/redirect.py
+++ b/server/src/uds/core/util/middleware/redirect.py
@@ -44,6 +44,7 @@ class RedirectMiddleware:
 
     Some paths will not be redirected, to avoid problems, but they are advised to use SSL (this is for backwards compat)
     """
+    __slots__ = ('get_response',)
 
     NO_REDIRECT: typing.ClassVar[typing.List[str]] = [
         'rest',
diff --git a/server/src/uds/core/util/middleware/request.py b/server/src/uds/core/util/middleware/request.py
index 0d3f244e9..557c22cdf 100644
--- a/server/src/uds/core/util/middleware/request.py
+++ b/server/src/uds/core/util/middleware/request.py
@@ -51,6 +51,8 @@ CHECK_SECONDS = 3600 * 24  # Once a day is more than enough
 
 
 class GlobalRequestMiddleware:
+    __slots__ = ('_get_response',)
+
     lastCheck: typing.ClassVar[datetime.datetime] = datetime.datetime.now()
 
     def __init__(self, get_response: typing.Callable[[HttpRequest], HttpResponse]):
diff --git a/server/src/uds/core/util/middleware/security.py b/server/src/uds/core/util/middleware/security.py
index b6a32411c..805a4e99c 100644
--- a/server/src/uds/core/util/middleware/security.py
+++ b/server/src/uds/core/util/middleware/security.py
@@ -46,6 +46,7 @@ class UDSSecurityMiddleware:
     '''
     This class contains all the security checks done by UDS in order to add some extra protection.
     '''
+    __slots__ = ('get_response',)
 
     get_response: typing.Any  # typing.Callable[['HttpRequest'], 'HttpResponse']
 
diff --git a/server/src/uds/core/util/middleware/xua.py b/server/src/uds/core/util/middleware/xua.py
index 6f5e3f941..32e73a27b 100644
--- a/server/src/uds/core/util/middleware/xua.py
+++ b/server/src/uds/core/util/middleware/xua.py
@@ -40,6 +40,7 @@ class XUACompatibleMiddleware:
     This header tells to Internet Explorer to render page with latest
     possible version or to use chrome frame if it is installed.
     """
+    __slots__ = ('get_response',)
 
     def __init__(self, get_response):
         self.get_response = get_response
diff --git a/server/src/uds/core/util/singleton.py b/server/src/uds/core/util/singleton.py
index 1a0ace018..024437623 100644
--- a/server/src/uds/core/util/singleton.py
+++ b/server/src/uds/core/util/singleton.py
@@ -8,14 +8,14 @@ class Singleton(type):
     class MyClass(metaclass=Singleton):
         ...
     '''
-    __instance: typing.Optional[typing.Any]
+    _instance: typing.Optional[typing.Any]
 
     # We use __init__ so we customise the created class from this metaclass    
     def __init__(self, *args, **kwargs) -> None:
-        self.__instance = None
+        self._instance = None
         super().__init__(*args, **kwargs)
 
     def __call__(self, *args, **kwargs) -> typing.Any:
-        if self.__instance is None:
-            self.__instance = super().__call__(*args, **kwargs)
-        return self.__instance
+        if self._instance is None:
+            self._instance = super().__call__(*args, **kwargs)
+        return self._instance
diff --git a/server/src/uds/core/util/unique_gid_generator.py b/server/src/uds/core/util/unique_gid_generator.py
index 17a029c1c..1f12a3576 100644
--- a/server/src/uds/core/util/unique_gid_generator.py
+++ b/server/src/uds/core/util/unique_gid_generator.py
@@ -38,6 +38,8 @@ logger = logging.getLogger(__name__)
 
 
 class UniqueGIDGenerator(UniqueIDGenerator):
+    __slots__ = ()
+
     def __init__(self, owner, baseName=None):
         super().__init__('id', owner, baseName)
 
diff --git a/server/src/uds/core/util/unique_id_generator.py b/server/src/uds/core/util/unique_id_generator.py
index c970b037f..3a1704222 100644
--- a/server/src/uds/core/util/unique_id_generator.py
+++ b/server/src/uds/core/util/unique_id_generator.py
@@ -53,7 +53,11 @@ class CreateNewIdException(Exception):
 
 
 class UniqueIDGenerator:
+    __slots__ = ('_owner', '_baseName')
+
+    # owner is the owner of the UniqueID
     _owner: str
+    # base name for filtering unique ids. (I.e. "mac", "ip", "ipv6" ....)
     _baseName: str
 
     def __init__(
diff --git a/server/src/uds/core/util/unique_mac_generator.py b/server/src/uds/core/util/unique_mac_generator.py
index ea4c1c97e..ea2511665 100644
--- a/server/src/uds/core/util/unique_mac_generator.py
+++ b/server/src/uds/core/util/unique_mac_generator.py
@@ -39,6 +39,8 @@ logger = logging.getLogger(__name__)
 
 
 class UniqueMacGenerator(UniqueIDGenerator):
+    __slots__ = ('_macRange',)
+
     def __init__(self, owner: str) -> None:
         super().__init__('mac', owner, '\tmac')
 
diff --git a/server/src/uds/core/util/unique_name_generator.py b/server/src/uds/core/util/unique_name_generator.py
index 325dc9b42..389274c87 100644
--- a/server/src/uds/core/util/unique_name_generator.py
+++ b/server/src/uds/core/util/unique_name_generator.py
@@ -39,6 +39,8 @@ logger = logging.getLogger(__name__)
 
 # noinspection PyMethodOverriding
 class UniqueNameGenerator(UniqueIDGenerator):
+    __slots__ = ()
+
     def __init__(self, owner):
         super().__init__('name', owner)
 
@@ -53,7 +55,7 @@ class UniqueNameGenerator(UniqueIDGenerator):
         maxVal = 10 ** length - 1
         return self.__toName(super().get(minVal, maxVal), length)
 
-    def transfer(self, baseName: str, name: str, toUNGen: 'UniqueNameGenerator'):  # type: ignore # pylint: disable=arguments-differ
+    def transfer(self, baseName: str, name: str, toUNGen: 'UniqueNameGenerator') -> None:  # type: ignore
         self.setBaseName(baseName)
         super().transfer(int(name[len(self._baseName) :]), toUNGen)
 
diff --git a/server/src/uds/core/util/validators.py b/server/src/uds/core/util/validators.py
index 797bd5126..7f254af9c 100644
--- a/server/src/uds/core/util/validators.py
+++ b/server/src/uds/core/util/validators.py
@@ -170,3 +170,21 @@ def validateMacRange(macRange: str) -> str:
         )
 
     return macRange
+
+def validateEmail(email: str) -> str:
+    """
+    Validates that an email is valid
+    :param email: email to validate
+    :return: Raises Module.Validation exception if is invalid, else return the value "fixed"
+    """
+    if len(email) > 254:
+        raise Module.ValidationException(
+            _('Email address is too long')
+        )
+
+    if not re.match(r"[^@]+@[^@]+\.[^@]+", email):
+        raise Module.ValidationException(
+            _('Email address is not valid')
+        )
+
+    return email