diff --git a/.github/scripts/version_check.py b/.github/scripts/version_check.py
index 4d596395a329..0c91797fb580 100644
--- a/.github/scripts/version_check.py
+++ b/.github/scripts/version_check.py
@@ -16,6 +16,7 @@
 import re
 import sys
 from pathlib import Path
+from typing import Optional
 
 import requests
 
@@ -48,7 +49,7 @@ def get_existing_release_tags(include_prerelease=True):
         tag = release['tag_name'].strip()
         match = re.match(r'^.*(\d+)\.(\d+)\.(\d+).*$', tag)
 
-        if len(match.groups()) != 3:
+        if not match or len(match.groups()) != 3:
             print(f"Version '{tag}' did not match expected pattern")
             continue
 
@@ -94,11 +95,12 @@ def check_version_number(version_string, allow_duplicate=False):
     return highest_release
 
 
-if __name__ == '__main__':
+def main() -> bool:
+    """Main function to check the version number."""
     # Ensure that we are running in GH Actions
     if os.environ.get('GITHUB_ACTIONS', '') != 'true':
         print('This script is intended to be run within a GitHub Action!')
-        sys.exit(1)
+        return False
 
     if 'only_version' in sys.argv:
         here = Path(__file__).parent.absolute()
@@ -111,7 +113,7 @@ def check_version_number(version_string, allow_duplicate=False):
         if len(sys.argv) > 2 and sys.argv[2] == 'true':
             results[0] = str(int(results[0]) - 1)
         print(results[0])
-        exit(0)
+        return True
 
     # GITHUB_REF_TYPE may be either 'branch' or 'tag'
     GITHUB_REF_TYPE = os.environ['GITHUB_REF_TYPE']
@@ -142,7 +144,7 @@ def check_version_number(version_string, allow_duplicate=False):
 
         if len(results) != 1:
             print(f'Could not find INVENTREE_SW_VERSION in {version_file}')
-            sys.exit(1)
+            return False
 
         version = results[0]
 
@@ -164,16 +166,16 @@ def check_version_number(version_string, allow_duplicate=False):
     highest_release = check_version_number(version, allow_duplicate=allow_duplicate)
 
     # Determine which docker tag we are going to use
-    docker_tags = None
+    docker_tags: Optional[list[str]] = None
 
     if GITHUB_REF_TYPE == 'tag':
         # GITHUB_REF should be of the form /refs/heads/<tag>
-        version_tag = GITHUB_REF.split('/')[-1]
+        version_tag: str = GITHUB_REF.split('/')[-1]
         print(f"Checking requirements for tagged release - '{version_tag}':")
 
         if version_tag != version:
             print(f"Version number '{version}' does not match tag '{version_tag}'")
-            sys.exit
+            return True
 
         docker_tags = [version_tag, 'stable'] if highest_release else [version_tag]
 
@@ -187,11 +189,11 @@ def check_version_number(version_string, allow_duplicate=False):
         print('GITHUB_REF_TYPE:', GITHUB_REF_TYPE)
         print('GITHUB_BASE_REF:', GITHUB_BASE_REF)
         print('GITHUB_REF:', GITHUB_REF)
-        sys.exit(1)
+        return False
 
     if docker_tags is None:
         print('Docker tags could not be determined')
-        sys.exit(1)
+        return False
 
     print(f"Version check passed for '{version}'!")
     print(f"Docker tags: '{docker_tags}'")
@@ -208,3 +210,11 @@ def check_version_number(version_string, allow_duplicate=False):
 
         if GITHUB_REF_TYPE == 'tag' and highest_release:
             env_file.write('stable_release=true\n')
+    return True
+
+
+if __name__ == '__main__':
+    rslt = main()
+    if rslt is not True:
+        print('Version check failed!')
+        sys.exit(1)
diff --git a/.github/workflows/qc_checks.yaml b/.github/workflows/qc_checks.yaml
index 3429ca47ead7..13d1c68831e2 100644
--- a/.github/workflows/qc_checks.yaml
+++ b/.github/workflows/qc_checks.yaml
@@ -97,6 +97,27 @@ jobs:
           pip install --require-hashes -r contrib/dev_reqs/requirements.txt
           python3 .github/scripts/version_check.py
 
+  typecheck:
+    name: Style [Typecheck]
+    runs-on: ubuntu-24.04
+    needs: [paths-filter, pre-commit]
+    if: needs.paths-filter.outputs.server == 'true' || needs.paths-filter.outputs.requirements == 'true' || needs.paths-filter.outputs.force == 'true'
+
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # pin@v4.2.2
+        with:
+          persist-credentials: false
+      - name: Environment Setup
+        id: setup
+        uses: ./.github/actions/setup
+        with:
+          apt-dependency: gettext poppler-utils
+          dev-install: true
+          update: true
+      - name: Check types
+        run: |
+          ty check --python ${Python_ROOT_DIR}/bin/python3
+
   mkdocs:
     name: Style [Documentation]
     runs-on: ubuntu-24.04
diff --git a/docs/docs/hooks.py b/docs/docs/hooks.py
index fe3f7096cf0d..090c54e51763 100644
--- a/docs/docs/hooks.py
+++ b/docs/docs/hooks.py
@@ -4,7 +4,7 @@
 import os
 import re
 from datetime import datetime
-from distutils.version import StrictVersion
+from distutils.version import StrictVersion  # type: ignore[import]
 from pathlib import Path
 
 import requests
diff --git a/docs/main.py b/docs/main.py
index 25b435c1919a..67ee3e245690 100644
--- a/docs/main.py
+++ b/docs/main.py
@@ -110,7 +110,7 @@ def check_link(url) -> bool:
     return False
 
 
-def get_build_environment() -> str:
+def get_build_environment() -> Optional[str]:
     """Returns the branch we are currently building on, based on the environment variables of the various CI platforms."""
     # Check if we are in ReadTheDocs
     if os.environ.get('READTHEDOCS') == 'True':
diff --git a/pyproject.toml b/pyproject.toml
index 04f341b5194c..1418b38acd03 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -101,6 +101,21 @@ python-version = "3.9.2"
 no-strip-extras=true
 generate-hashes=true
 
+[tool.ty]
+src = [
+    "src/backend/InvenTree",
+    "./",
+]
+[tool.ty.rules]
+unresolved-reference="ignore"  # 24 # see https://github.com/astral-sh/ty/issues/220
+unresolved-attribute="ignore"  # 33 # need Plugin Mixin typing
+call-non-callable="ignore"  # 3 ##
+invalid-return-type="ignore"  # 12 ##
+invalid-argument-type="ignore"  # 15
+possibly-unbound-attribute="ignore"  # 7
+unknown-argument="ignore"  # 9  # need to wait for betterdjango field stubs
+
+
 [tool.coverage.run]
 source = ["src/backend/InvenTree", "InvenTree"]
 dynamic_context = "test_function"
diff --git a/src/backend/InvenTree/InvenTree/api.py b/src/backend/InvenTree/InvenTree/api.py
index e5535e26f53c..0cc2a51611d2 100644
--- a/src/backend/InvenTree/InvenTree/api.py
+++ b/src/backend/InvenTree/InvenTree/api.py
@@ -17,6 +17,7 @@
 from rest_framework.serializers import ValidationError
 from rest_framework.views import APIView
 
+import InvenTree.permissions
 import InvenTree.version
 from common.settings import get_global_setting
 from InvenTree import helpers
diff --git a/src/backend/InvenTree/InvenTree/apps.py b/src/backend/InvenTree/InvenTree/apps.py
index ea13d092ccc1..720e4c566f40 100644
--- a/src/backend/InvenTree/InvenTree/apps.py
+++ b/src/backend/InvenTree/InvenTree/apps.py
@@ -134,6 +134,9 @@ def start_background_tasks(self):
         tasks = InvenTree.tasks.tasks.task_list
 
         for task in tasks:
+            if not task:
+                continue  # pragma: no cover
+
             ref_name = f'{task.func.__module__}.{task.func.__name__}'
 
             if ref_name in existing_tasks:
diff --git a/src/backend/InvenTree/InvenTree/cache.py b/src/backend/InvenTree/InvenTree/cache.py
index a217c94fe1cc..97beb96c36d7 100644
--- a/src/backend/InvenTree/InvenTree/cache.py
+++ b/src/backend/InvenTree/InvenTree/cache.py
@@ -2,6 +2,7 @@
 
 import socket
 import threading
+from typing import Any
 
 import structlog
 
@@ -127,7 +128,7 @@ def delete_session_cache() -> None:
         del thread_data.request_cache
 
 
-def get_session_cache(key: str) -> any:
+def get_session_cache(key: str) -> Any:
     """Return a cached value from the session cache."""
     # Only return a cached value if the request object is available too
     if not hasattr(thread_data, 'request'):
@@ -139,7 +140,7 @@ def get_session_cache(key: str) -> any:
         return val
 
 
-def set_session_cache(key: str, value: any) -> None:
+def set_session_cache(key: str, value: Any) -> None:
     """Set a cached value in the session cache."""
     # Only set a cached value if the request object is available too
     if not hasattr(thread_data, 'request'):
diff --git a/src/backend/InvenTree/InvenTree/config.py b/src/backend/InvenTree/InvenTree/config.py
index 02326f0e90bd..dcc49106977f 100644
--- a/src/backend/InvenTree/InvenTree/config.py
+++ b/src/backend/InvenTree/InvenTree/config.py
@@ -8,6 +8,7 @@
 import shutil
 import string
 from pathlib import Path
+from typing import Union
 
 logger = logging.getLogger('inventree')
 CONFIG_DATA = None
@@ -113,7 +114,7 @@ def get_config_file(create=True) -> Path:
     return cfg_filename
 
 
-def load_config_data(set_cache: bool = False) -> map:
+def load_config_data(set_cache: bool = False) -> Union[map, None]:
     """Load configuration data from the config file.
 
     Arguments:
diff --git a/src/backend/InvenTree/InvenTree/conversion.py b/src/backend/InvenTree/InvenTree/conversion.py
index 669fe950fff2..295a2e9fbc80 100644
--- a/src/backend/InvenTree/InvenTree/conversion.py
+++ b/src/backend/InvenTree/InvenTree/conversion.py
@@ -191,7 +191,7 @@ def convert_physical_value(value: str, unit: Optional[str] = None, strip_units=T
         attempts.append(f'{value}{unit}')
         attempts.append(f'{eng}{unit}')
 
-    value = None
+    value: Optional[str] = None
 
     # Run through the available "attempts", take the first successful result
     for attempt in attempts:
diff --git a/src/backend/InvenTree/InvenTree/exceptions.py b/src/backend/InvenTree/InvenTree/exceptions.py
index ac84befa93d1..07ec874ddb4c 100644
--- a/src/backend/InvenTree/InvenTree/exceptions.py
+++ b/src/backend/InvenTree/InvenTree/exceptions.py
@@ -50,7 +50,8 @@ def log_error(path, error_name=None, error_info=None, error_data=None):
         data = error_data
     else:
         try:
-            data = '\n'.join(traceback.format_exception(kind, info, data))
+            formatted_exception = traceback.format_exception(kind, info, data)  # type: ignore[no-matching-overload]
+            data = '\n'.join(formatted_exception)
         except AttributeError:
             data = 'No traceback information available'
 
diff --git a/src/backend/InvenTree/InvenTree/filters.py b/src/backend/InvenTree/InvenTree/filters.py
index 30745679a026..d6906279fdaf 100644
--- a/src/backend/InvenTree/InvenTree/filters.py
+++ b/src/backend/InvenTree/InvenTree/filters.py
@@ -6,7 +6,8 @@
 from django.utils import timezone
 from django.utils.timezone import make_aware
 
-from django_filters import rest_framework as rest_filters
+import django_filters.rest_framework.backends as drf_backend
+import django_filters.rest_framework.filters as rest_filters
 from rest_framework import filters
 
 import InvenTree.helpers
@@ -20,7 +21,7 @@ def filter(self, qs, value):
         if settings.USE_TZ and value is not None:
             tz = timezone.get_current_timezone()
             value = datetime(value.year, value.month, value.day)
-            value = make_aware(value, tz, True)
+            value = make_aware(value, timezone=tz, is_dst=True)
 
         return super().filter(qs, value)
 
@@ -160,17 +161,17 @@ def get_ordering(self, request, queryset, view):
 
 
 SEARCH_ORDER_FILTER = [
-    rest_filters.DjangoFilterBackend,
+    drf_backend.DjangoFilterBackend,
     InvenTreeSearchFilter,
     filters.OrderingFilter,
 ]
 
 SEARCH_ORDER_FILTER_ALIAS = [
-    rest_filters.DjangoFilterBackend,
+    drf_backend.DjangoFilterBackend,
     InvenTreeSearchFilter,
     InvenTreeOrderingFilter,
 ]
 
-ORDER_FILTER = [rest_filters.DjangoFilterBackend, filters.OrderingFilter]
+ORDER_FILTER = [drf_backend.DjangoFilterBackend, filters.OrderingFilter]
 
-ORDER_FILTER_ALIAS = [rest_filters.DjangoFilterBackend, InvenTreeOrderingFilter]
+ORDER_FILTER_ALIAS = [drf_backend.DjangoFilterBackend, InvenTreeOrderingFilter]
diff --git a/src/backend/InvenTree/InvenTree/format.py b/src/backend/InvenTree/InvenTree/format.py
index 5fc8c546bb74..3ee674b216a9 100644
--- a/src/backend/InvenTree/InvenTree/format.py
+++ b/src/backend/InvenTree/InvenTree/format.py
@@ -107,7 +107,7 @@ def construct_format_regex(fmt_string: str) -> str:
         # Add a named capture group for the format entry
         if name:
             # Check if integer values are required
-            c = '\\d' if _fmt.endswith('d') else '.'
+            c = '\\d' if _fmt and _fmt.endswith('d') else '.'
 
             # Specify width
             # TODO: Introspect required width
@@ -124,7 +124,7 @@ def construct_format_regex(fmt_string: str) -> str:
     return pattern
 
 
-def validate_string(value: str, fmt_string: str) -> str:
+def validate_string(value: str, fmt_string: str) -> bool:
     """Validate that the provided string matches the specified format.
 
     Args:
diff --git a/src/backend/InvenTree/InvenTree/helpers.py b/src/backend/InvenTree/InvenTree/helpers.py
index ee6ffe642c1f..8271deb70de3 100644
--- a/src/backend/InvenTree/InvenTree/helpers.py
+++ b/src/backend/InvenTree/InvenTree/helpers.py
@@ -8,7 +8,7 @@
 import os.path
 import re
 from decimal import Decimal, InvalidOperation
-from typing import Optional, TypeVar
+from typing import Optional, TypeVar, Union
 from wsgiref.util import FileWrapper
 from zoneinfo import ZoneInfo, ZoneInfoNotFoundError
 
@@ -21,6 +21,8 @@
 from django.utils.translation import gettext_lazy as _
 
 import bleach
+import bleach.css_sanitizer
+import bleach.sanitizer
 import structlog
 from bleach import clean
 from djmoney.money import Money
@@ -123,7 +125,7 @@ def do_clip(value: int, clip: int, allow_negative: bool) -> int:
     return ref_int
 
 
-def generateTestKey(test_name: str) -> str:
+def generateTestKey(test_name: Union[str, None]) -> str:
     """Generate a test 'key' for a given test name. This must not have illegal chars as it will be used for dict lookup in a template.
 
     Tests must be named such that they will have unique keys.
@@ -362,9 +364,7 @@ def increment(value):
     except ValueError:
         pass
 
-    number = number.zfill(width)
-
-    return prefix + number
+    return prefix + str(number).zfill(width)
 
 
 def decimal2string(d):
@@ -949,7 +949,7 @@ def current_time(local=True):
     """
     if settings.USE_TZ:
         now = timezone.now()
-        now = to_local_time(now, target_tz=server_timezone() if local else 'UTC')
+        now = to_local_time(now, target_tz_str=server_timezone() if local else 'UTC')
         return now
     else:
         return datetime.datetime.now()
@@ -968,12 +968,12 @@ def server_timezone() -> str:
     return settings.TIME_ZONE
 
 
-def to_local_time(time, target_tz: Optional[str] = None):
+def to_local_time(time, target_tz_str: Optional[str] = None):
     """Convert the provided time object to the local timezone.
 
     Arguments:
         time: The time / date to convert
-        target_tz: The desired timezone (string) - defaults to server time
+        target_tz_str: The desired timezone (string) - defaults to server time
 
     Returns:
         A timezone aware datetime object, with the desired timezone
@@ -997,11 +997,11 @@ def to_local_time(time, target_tz: Optional[str] = None):
         # Default to UTC if not provided
         source_tz = ZoneInfo('UTC')
 
-    if not target_tz:
-        target_tz = server_timezone()
+    if not target_tz_str:
+        target_tz_str = server_timezone()
 
     try:
-        target_tz = ZoneInfo(str(target_tz))
+        target_tz = ZoneInfo(str(target_tz_str))
     except ZoneInfoNotFoundError:
         target_tz = ZoneInfo('UTC')
 
diff --git a/src/backend/InvenTree/InvenTree/helpers_email.py b/src/backend/InvenTree/InvenTree/helpers_email.py
index e8fb6b6476dc..9ec41ae7470a 100644
--- a/src/backend/InvenTree/InvenTree/helpers_email.py
+++ b/src/backend/InvenTree/InvenTree/helpers_email.py
@@ -1,5 +1,7 @@
 """Code for managing email functionality in InvenTree."""
 
+from typing import Optional
+
 from django.conf import settings
 from django.core import mail as django_mail
 
@@ -91,7 +93,7 @@ def send_email(subject, body, recipients, from_email=None, html_message=None):
     )
 
 
-def get_email_for_user(user) -> str:
+def get_email_for_user(user) -> Optional[str]:
     """Find an email address for the specified user."""
     # First check if the user has an associated email address
     if user.email:
diff --git a/src/backend/InvenTree/InvenTree/helpers_model.py b/src/backend/InvenTree/InvenTree/helpers_model.py
index 23a7c71f1c12..62710407d8cb 100644
--- a/src/backend/InvenTree/InvenTree/helpers_model.py
+++ b/src/backend/InvenTree/InvenTree/helpers_model.py
@@ -11,6 +11,7 @@
 from django.utils.translation import gettext_lazy as _
 
 import requests
+import requests.exceptions
 import structlog
 from djmoney.contrib.exchange.models import convert_money
 from djmoney.money import Money
@@ -328,8 +329,9 @@ def notify_users(
         'template': {'subject': content.name.format(**content_context)},
     }
 
-    if content.template:
-        context['template']['html'] = content.template.format(**content_context)
+    tmp = content.template
+    if tmp:
+        context['template']['html'] = tmp.format(**content_context)
 
     # Create notification
     trigger_notification(
diff --git a/src/backend/InvenTree/InvenTree/management/commands/schema.py b/src/backend/InvenTree/InvenTree/management/commands/schema.py
index ae07c8b41ed7..22368c74c728 100644
--- a/src/backend/InvenTree/InvenTree/management/commands/schema.py
+++ b/src/backend/InvenTree/InvenTree/management/commands/schema.py
@@ -1,7 +1,7 @@
 """Extended schema generator."""
 
 from pathlib import Path
-from typing import TypeVar
+from typing import TypeVar, Union
 
 from django.conf import settings
 
@@ -26,7 +26,7 @@ def prep_name(ref):
     return f'{dja_ref_prefix}.{ref}'
 
 
-def sub_component_name(name: T) -> T:
+def sub_component_name(name: T) -> Union[T, str]:
     """Clean up component references."""
     if not isinstance(name, str):
         return name
diff --git a/src/backend/InvenTree/InvenTree/management/commands/wait_for_db.py b/src/backend/InvenTree/InvenTree/management/commands/wait_for_db.py
index 6bfdc98b5828..68b33adfff9f 100644
--- a/src/backend/InvenTree/InvenTree/management/commands/wait_for_db.py
+++ b/src/backend/InvenTree/InvenTree/management/commands/wait_for_db.py
@@ -2,9 +2,10 @@
 
 import time
 
+from django.core.exceptions import ImproperlyConfigured
 from django.core.management.base import BaseCommand
 from django.db import connection
-from django.db.utils import ImproperlyConfigured, OperationalError
+from django.db.utils import OperationalError
 
 
 class Command(BaseCommand):
diff --git a/src/backend/InvenTree/InvenTree/models.py b/src/backend/InvenTree/InvenTree/models.py
index 24d6ea649fd9..0abcbce0b1d0 100644
--- a/src/backend/InvenTree/InvenTree/models.py
+++ b/src/backend/InvenTree/InvenTree/models.py
@@ -994,7 +994,7 @@ def assign_barcode(
             raise ValueError("Provide either 'barcode_hash' or 'barcode_data'")
 
         # If barcode_hash is not provided, create from supplier barcode_data
-        if barcode_hash is None:
+        if barcode_hash is None and barcode_data is not None:
             barcode_hash = InvenTree.helpers.hash_barcode(barcode_data)
 
         # Check for existing item
diff --git a/src/backend/InvenTree/InvenTree/permissions.py b/src/backend/InvenTree/InvenTree/permissions.py
index c78a24f38443..059bbd9ccb9b 100644
--- a/src/backend/InvenTree/InvenTree/permissions.py
+++ b/src/backend/InvenTree/InvenTree/permissions.py
@@ -249,7 +249,9 @@ def has_permission(self, request, view):
     def get_required_alternate_scopes(self, request, view):
         """Return the required scopes for the current request."""
         scopes = map_scope(
-            only_read=True, read_name=DEFAULT_STAFF, map_read=permissions.SAFE_METHODS
+            only_read=True,
+            read_name=DEFAULT_STAFF,
+            map_read=list(permissions.SAFE_METHODS),
         )
         return scopes
 
@@ -287,7 +289,7 @@ def get_required_alternate_scopes(self, request, view):
         return map_scope(
             only_read=True,
             read_name=DEFAULT_SUPERUSER,
-            map_read=permissions.SAFE_METHODS,
+            map_read=list(permissions.SAFE_METHODS),
         )
 
 
@@ -312,7 +314,9 @@ def has_permission(self, request, view):
     def get_required_alternate_scopes(self, request, view):
         """Return the required scopes for the current request."""
         return map_scope(
-            only_read=True, read_name=DEFAULT_STAFF, map_read=permissions.SAFE_METHODS
+            only_read=True,
+            read_name=DEFAULT_STAFF,
+            map_read=list(permissions.SAFE_METHODS),
         )
 
 
@@ -342,7 +346,7 @@ def auth_exempt(view_func):
     def wrapped_view(*args, **kwargs):
         return view_func(*args, **kwargs)
 
-    wrapped_view.auth_exempt = True
+    wrapped_view.auth_exempt = True  # type:ignore[unresolved-attribute]
     return wraps(view_func)(wrapped_view)
 
 
@@ -382,5 +386,7 @@ def has_permission(self, request, view):
     def get_required_alternate_scopes(self, request, view):
         """Return the required scopes for the current request."""
         return map_scope(
-            only_read=True, read_name=DEFAULT_STAFF, map_read=permissions.SAFE_METHODS
+            only_read=True,
+            read_name=DEFAULT_STAFF,
+            map_read=list(permissions.SAFE_METHODS),
         )
diff --git a/src/backend/InvenTree/InvenTree/sanitizer.py b/src/backend/InvenTree/InvenTree/sanitizer.py
index 0272b50f943c..ce093b96fec5 100644
--- a/src/backend/InvenTree/InvenTree/sanitizer.py
+++ b/src/backend/InvenTree/InvenTree/sanitizer.py
@@ -188,8 +188,8 @@
 def sanitize_svg(
     file_data,
     strip: bool = True,
-    elements: str = ALLOWED_ELEMENTS_SVG,
-    attributes: str = ALLOWED_ATTRIBUTES_SVG,
+    elements: list[str] = ALLOWED_ELEMENTS_SVG,
+    attributes: list[str] = ALLOWED_ATTRIBUTES_SVG,
 ) -> str:
     """Sanitize a SVG file.
 
diff --git a/src/backend/InvenTree/InvenTree/serializers.py b/src/backend/InvenTree/InvenTree/serializers.py
index 9aa653c1af58..59cbb8153274 100644
--- a/src/backend/InvenTree/InvenTree/serializers.py
+++ b/src/backend/InvenTree/InvenTree/serializers.py
@@ -373,16 +373,15 @@ def run_validation(self, data=empty):
             instance.full_clean()
         except (ValidationError, DjangoValidationError) as exc:
             if hasattr(exc, 'message_dict'):
-                data = exc.message_dict
+                data = {**exc.message_dict}
             elif hasattr(exc, 'message'):
                 data = {'non_field_errors': [str(exc.message)]}
             else:
                 data = {'non_field_errors': [str(exc)]}
 
             # Change '__all__' key (django style) to 'non_field_errors' (DRF style)
-            if '__all__' in data:
-                data['non_field_errors'] = data['__all__']
-                del data['__all__']
+            if hasattr(data, '__all__'):
+                data['non_field_errors'] = data.pop('__all__')
 
             raise ValidationError(data)
 
diff --git a/src/backend/InvenTree/InvenTree/settings.py b/src/backend/InvenTree/InvenTree/settings.py
index 95a338833002..a62c997e4428 100644
--- a/src/backend/InvenTree/InvenTree/settings.py
+++ b/src/backend/InvenTree/InvenTree/settings.py
@@ -38,6 +38,13 @@
 
 from . import config, locales
 
+try:
+    import django_stubs_ext
+
+    django_stubs_ext.monkeypatch()  # pragma: no cover
+except ImportError:  # pragma: no cover
+    pass
+
 checkMinPythonVersion()
 
 INVENTREE_BASE_URL = 'https://inventree.org'
@@ -310,31 +317,31 @@
     'django_ical',  # For exporting calendars
 ]
 
-MIDDLEWARE = CONFIG.get(
-    'middleware',
-    [
-        'django.middleware.security.SecurityMiddleware',
-        'x_forwarded_for.middleware.XForwardedForMiddleware',
-        'django.contrib.sessions.middleware.SessionMiddleware',
-        'allauth.usersessions.middleware.UserSessionsMiddleware',  # DB user sessions
-        'django.middleware.locale.LocaleMiddleware',
-        'django.middleware.csrf.CsrfViewMiddleware',
-        'corsheaders.middleware.CorsMiddleware',
-        'whitenoise.middleware.WhiteNoiseMiddleware',
-        'django.middleware.common.CommonMiddleware',
-        'django.contrib.auth.middleware.AuthenticationMiddleware',
-        'InvenTree.middleware.InvenTreeRemoteUserMiddleware',  # Remote / proxy auth
-        'allauth.account.middleware.AccountMiddleware',
-        'django.contrib.messages.middleware.MessageMiddleware',
-        'django.middleware.clickjacking.XFrameOptionsMiddleware',
-        'InvenTree.middleware.AuthRequiredMiddleware',
-        'InvenTree.middleware.Check2FAMiddleware',  # Check if the user should be forced to use MFA
-        'oauth2_provider.middleware.OAuth2TokenMiddleware',  # oauth2_provider
-        'maintenance_mode.middleware.MaintenanceModeMiddleware',
-        'InvenTree.middleware.InvenTreeExceptionProcessor',  # Error reporting
-        'InvenTree.middleware.InvenTreeRequestCacheMiddleware',  # Request caching
-        'django_structlog.middlewares.RequestMiddleware',  # Structured logging
-    ],
+default_middleware = [
+    'django.middleware.security.SecurityMiddleware',
+    'x_forwarded_for.middleware.XForwardedForMiddleware',
+    'django.contrib.sessions.middleware.SessionMiddleware',
+    'allauth.usersessions.middleware.UserSessionsMiddleware',  # DB user sessions
+    'django.middleware.locale.LocaleMiddleware',
+    'django.middleware.csrf.CsrfViewMiddleware',
+    'corsheaders.middleware.CorsMiddleware',
+    'whitenoise.middleware.WhiteNoiseMiddleware',
+    'django.middleware.common.CommonMiddleware',
+    'django.contrib.auth.middleware.AuthenticationMiddleware',
+    'InvenTree.middleware.InvenTreeRemoteUserMiddleware',  # Remote / proxy auth
+    'allauth.account.middleware.AccountMiddleware',
+    'django.contrib.messages.middleware.MessageMiddleware',
+    'django.middleware.clickjacking.XFrameOptionsMiddleware',
+    'InvenTree.middleware.AuthRequiredMiddleware',
+    'InvenTree.middleware.Check2FAMiddleware',  # Check if the user should be forced to use MFA
+    'oauth2_provider.middleware.OAuth2TokenMiddleware',  # oauth2_provider
+    'maintenance_mode.middleware.MaintenanceModeMiddleware',
+    'InvenTree.middleware.InvenTreeExceptionProcessor',  # Error reporting
+    'InvenTree.middleware.InvenTreeRequestCacheMiddleware',  # Request caching
+    'django_structlog.middlewares.RequestMiddleware',  # Structured logging
+]
+MIDDLEWARE = (
+    CONFIG.get('middleware', default_middleware) if CONFIG else default_middleware
 )
 
 # In DEBUG mode, add support for django-querycount
@@ -359,22 +366,25 @@
 }
 
 
-AUTHENTICATION_BACKENDS = CONFIG.get(
-    'authentication_backends',
-    [
-        'oauth2_provider.backends.OAuth2Backend',  # OAuth2 provider
-        'django.contrib.auth.backends.RemoteUserBackend',  # proxy login
-        'django.contrib.auth.backends.ModelBackend',
-        'allauth.account.auth_backends.AuthenticationBackend',  # SSO login via external providers
-        'sesame.backends.ModelBackend',  # Magic link login django-sesame
-    ],
+default_auth_backends = [
+    'oauth2_provider.backends.OAuth2Backend',  # OAuth2 provider
+    'django.contrib.auth.backends.RemoteUserBackend',  # proxy login
+    'django.contrib.auth.backends.ModelBackend',
+    'allauth.account.auth_backends.AuthenticationBackend',  # SSO login via external providers
+    'sesame.backends.ModelBackend',  # Magic link login django-sesame
+]
+
+AUTHENTICATION_BACKENDS = (
+    CONFIG.get('authentication_backends', default_auth_backends)
+    if CONFIG
+    else default_auth_backends
 )
 
 # LDAP support
 LDAP_AUTH = get_boolean_setting('INVENTREE_LDAP_ENABLED', 'ldap.enabled', False)
 if LDAP_AUTH:
-    import django_auth_ldap.config
-    import ldap
+    import django_auth_ldap.config  # type: ignore[unresolved-import]
+    import ldap  # type: ignore[unresolved-import]
 
     AUTHENTICATION_BACKENDS.append('django_auth_ldap.backend.LDAPBackend')
 
@@ -427,7 +437,7 @@
     )
     AUTH_LDAP_USER_SEARCH = django_auth_ldap.config.LDAPSearch(
         get_setting('INVENTREE_LDAP_SEARCH_BASE_DN', 'ldap.search_base_dn'),
-        ldap.SCOPE_SUBTREE,
+        ldap.SCOPE_SUBTREE,  # type: ignore[unresolved-attribute]
         str(
             get_setting(
                 'INVENTREE_LDAP_SEARCH_FILTER_STR',
@@ -463,7 +473,7 @@
     )
     AUTH_LDAP_GROUP_SEARCH = django_auth_ldap.config.LDAPSearch(
         get_setting('INVENTREE_LDAP_GROUP_SEARCH', 'ldap.group_search'),
-        ldap.SCOPE_SUBTREE,
+        ldap.SCOPE_SUBTREE,  # type: ignore[unresolved-attribute]
         f'(objectClass={AUTH_LDAP_GROUP_OBJECT_CLASS})',
     )
     AUTH_LDAP_GROUP_TYPE_CLASS = get_setting(
@@ -590,7 +600,7 @@
 logger.debug('Configuring database backend:')
 
 # Extract database configuration from the config.yaml file
-db_config = CONFIG.get('database', None)
+db_config = CONFIG.get('database', None) if CONFIG else None
 
 if not db_config:
     db_config = {}
@@ -676,7 +686,9 @@
 
 # Specific options for postgres backend
 if 'postgres' in db_engine:  # pragma: no cover
-    from django.db.backends.postgresql.psycopg_any import IsolationLevel
+    from django.db.backends.postgresql.psycopg_any import (  # type: ignore[unresolved-import]
+        IsolationLevel,
+    )
 
     # Connection timeout
     if 'connect_timeout' not in db_options:
diff --git a/src/backend/InvenTree/InvenTree/sso.py b/src/backend/InvenTree/InvenTree/sso.py
index c1842d70de49..441a7a6fd912 100644
--- a/src/backend/InvenTree/InvenTree/sso.py
+++ b/src/backend/InvenTree/InvenTree/sso.py
@@ -50,7 +50,7 @@ def check_provider(provider):
     if not app:
         return False
 
-    if allauth.app_settings.SITES_ENABLED:
+    if allauth.app_settings.SITES_ENABLED:  # type: ignore[unresolved-attribute]
         # At least one matching site must be specified
         if not app.sites.exists():
             logger.error('SocialApp %s has no sites configured', app)
diff --git a/src/backend/InvenTree/InvenTree/tasks.py b/src/backend/InvenTree/InvenTree/tasks.py
index 5c39b8e08359..cb102c3ec561 100644
--- a/src/backend/InvenTree/InvenTree/tasks.py
+++ b/src/backend/InvenTree/InvenTree/tasks.py
@@ -288,7 +288,7 @@ class ScheduledTask:
     QUARTERLY: str = 'Q'
     YEARLY: str = 'Y'
 
-    TYPE: tuple[str] = (MINUTES, HOURLY, DAILY, WEEKLY, MONTHLY, QUARTERLY, YEARLY)
+    TYPE: tuple[str] = (MINUTES, HOURLY, DAILY, WEEKLY, MONTHLY, QUARTERLY, YEARLY)  # type: ignore[invalid-assignment]
 
 
 class TaskRegister:
@@ -305,7 +305,9 @@ def register(self, task, schedule, minutes: Optional[int] = None):
 
 
 def scheduled_task(
-    interval: str, minutes: Optional[int] = None, tasklist: TaskRegister = None
+    interval: str,
+    minutes: Optional[int] = None,
+    tasklist: Optional[TaskRegister] = None,
 ):
     """Register the given task as a scheduled task.
 
@@ -512,7 +514,7 @@ def check_for_updates():
 
     match = re.match(r'^.*(\d+)\.(\d+)\.(\d+).*$', tag)
 
-    if len(match.groups()) != 3:  # pragma: no cover
+    if not match or len(match.groups()) != 3:  # pragma: no cover
         logger.warning("Version '%s' did not match expected pattern", tag)
         return
 
diff --git a/src/backend/InvenTree/InvenTree/test_api.py b/src/backend/InvenTree/InvenTree/test_api.py
index 289a204a94fc..95aa69054ac9 100644
--- a/src/backend/InvenTree/InvenTree/test_api.py
+++ b/src/backend/InvenTree/InvenTree/test_api.py
@@ -567,7 +567,7 @@ def test_api_license(self):
 
             self.assertIn('License file not found at', str(log.output))
 
-        with TemporaryDirectory() as tmp:
+        with TemporaryDirectory() as tmp:  # type: ignore[no-matching-overload]
             sample_file = Path(tmp, 'temp.txt')
             sample_file.write_text('abc')
 
diff --git a/src/backend/InvenTree/InvenTree/tracing.py b/src/backend/InvenTree/InvenTree/tracing.py
index a04a71c9e2c0..44151d470c85 100644
--- a/src/backend/InvenTree/InvenTree/tracing.py
+++ b/src/backend/InvenTree/InvenTree/tracing.py
@@ -4,7 +4,7 @@
 import logging
 from typing import Optional
 
-from opentelemetry import metrics, trace
+from opentelemetry import metrics, trace  # type: ignore[import]
 from opentelemetry.instrumentation.django import DjangoInstrumentor
 from opentelemetry.instrumentation.redis import RedisInstrumentor
 from opentelemetry.instrumentation.requests import RequestsInstrumentor
diff --git a/src/backend/InvenTree/InvenTree/unit_test.py b/src/backend/InvenTree/InvenTree/unit_test.py
index 23600e81ca6b..6777ee1270ca 100644
--- a/src/backend/InvenTree/InvenTree/unit_test.py
+++ b/src/backend/InvenTree/InvenTree/unit_test.py
@@ -76,7 +76,7 @@ def getOldestMigrationFile(app, exclude_extension=True, ignore_initial=True):
             oldest_num = num
             oldest_file = f
 
-    if exclude_extension:
+    if exclude_extension and oldest_file:
         oldest_file = oldest_file.replace('.py', '')
 
     return oldest_file
@@ -518,6 +518,10 @@ def download_file(
         result = re.search(
             r'(attachment|inline); filename=[\'"]([\w\d\-.]+)[\'"]', disposition
         )
+        if not result:
+            raise ValueError(
+                'No filename match found in disposition'
+            )  # pragma: no cover
 
         fn = result.groups()[1]
 
diff --git a/src/backend/InvenTree/InvenTree/validators.py b/src/backend/InvenTree/InvenTree/validators.py
index 6a0fe6cd9d4e..3c85483c4bfa 100644
--- a/src/backend/InvenTree/InvenTree/validators.py
+++ b/src/backend/InvenTree/InvenTree/validators.py
@@ -8,6 +8,7 @@
 from django.utils.translation import gettext_lazy as _
 
 import pint
+import pint.errors
 from moneyed import CURRENCIES
 
 import InvenTree.conversion
diff --git a/src/backend/InvenTree/InvenTree/version.py b/src/backend/InvenTree/InvenTree/version.py
index 5ee6f1af662f..7c9cbb10b46e 100644
--- a/src/backend/InvenTree/InvenTree/version.py
+++ b/src/backend/InvenTree/InvenTree/version.py
@@ -107,7 +107,7 @@ def inventreeVersionTuple(version=None):
 
     match = re.match(r'^.*(\d+)\.(\d+)\.(\d+).*$', str(version))
 
-    return [int(g) for g in match.groups()]
+    return [int(g) for g in match.groups()] if match else []
 
 
 def isInvenTreeDevelopmentVersion():
diff --git a/src/backend/InvenTree/build/api.py b/src/backend/InvenTree/build/api.py
index 1b017d73dcc2..f4202f921f29 100644
--- a/src/backend/InvenTree/build/api.py
+++ b/src/backend/InvenTree/build/api.py
@@ -2,17 +2,20 @@
 
 from __future__ import annotations
 
+from typing import Optional
+
 from django.contrib.auth.models import User
 from django.db.models import F, Q
 from django.urls import include, path
 from django.utils.translation import gettext_lazy as _
 
-from django_filters import rest_framework as rest_filters
+import django_filters.rest_framework.filters as rest_filters
+from django_filters.rest_framework.filterset import FilterSet
 from drf_spectacular.utils import extend_schema_field
 from rest_framework import serializers
 from rest_framework.exceptions import ValidationError
 
-import build.admin
+import build.models as build_models
 import build.serializers
 import common.models
 import part.models as part_models
@@ -27,7 +30,7 @@
 from users.models import Owner
 
 
-class BuildFilter(rest_filters.FilterSet):
+class BuildFilter(FilterSet):
     """Custom filterset for BuildList API endpoint."""
 
     class Meta:
@@ -439,7 +442,7 @@ def get_serializer_context(self):
         return ctx
 
 
-class BuildLineFilter(rest_filters.FilterSet):
+class BuildLineFilter(FilterSet):
     """Custom filterset for the BuildLine API endpoint."""
 
     class Meta:
@@ -600,7 +603,7 @@ class BuildLineList(BuildLineEndpoint, DataExportViewMixin, ListCreateAPI):
         'bom_item__reference',
     ]
 
-    def get_source_build(self) -> Build | None:
+    def get_source_build(self) -> Optional[Build]:
         """Return the target build for the BuildLine queryset."""
         source_build = None
 
@@ -617,7 +620,7 @@ def get_source_build(self) -> Build | None:
 class BuildLineDetail(BuildLineEndpoint, RetrieveUpdateDestroyAPI):
     """API endpoint for detail view of a BuildLine object."""
 
-    def get_source_build(self) -> Build | None:
+    def get_source_build(self) -> Optional[Build]:
         """Return the target source location for the BuildLine queryset."""
         return None
 
@@ -755,7 +758,7 @@ class BuildItemDetail(RetrieveUpdateDestroyAPI):
     serializer_class = build.serializers.BuildItemSerializer
 
 
-class BuildItemFilter(rest_filters.FilterSet):
+class BuildItemFilter(FilterSet):
     """Custom filterset for the BuildItemList API endpoint."""
 
     class Meta:
@@ -801,7 +804,7 @@ def filter_part(self, queryset, name, part):
             return queryset.filter(stock_item__part=part)
 
     build = rest_filters.ModelChoiceFilter(
-        queryset=build.models.Build.objects.all(),
+        queryset=build_models.Build.objects.all(),
         label=_('Build Order'),
         field_name='build_line__build',
     )
diff --git a/src/backend/InvenTree/build/models.py b/src/backend/InvenTree/build/models.py
index 37e3e4faa7c4..91ddebb4bd70 100644
--- a/src/backend/InvenTree/build/models.py
+++ b/src/backend/InvenTree/build/models.py
@@ -1307,7 +1307,7 @@ def stock_sort(item, bom_item, variant_parts):
                         except (ValidationError, serializers.ValidationError) as exc:
                             # Catch model errors and re-throw as DRF errors
                             raise ValidationError(
-                                detail=serializers.as_serializer_error(exc)
+                                exc.message, detail=serializers.as_serializer_error(exc)
                             )
 
                     if unallocated_quantity <= 0:
diff --git a/src/backend/InvenTree/build/serializers.py b/src/backend/InvenTree/build/serializers.py
index aaef6bae8182..2f83f7167ae7 100644
--- a/src/backend/InvenTree/build/serializers.py
+++ b/src/backend/InvenTree/build/serializers.py
@@ -23,6 +23,7 @@
 
 import build.tasks
 import common.models
+import common.settings
 import company.serializers
 import InvenTree.helpers
 import InvenTree.tasks
diff --git a/src/backend/InvenTree/build/test_api.py b/src/backend/InvenTree/build/test_api.py
index a29d64143a22..1c118a775490 100644
--- a/src/backend/InvenTree/build/test_api.py
+++ b/src/backend/InvenTree/build/test_api.py
@@ -1,6 +1,7 @@
 """Unit tests for the BuildOrder API."""
 
 from datetime import datetime, timedelta
+from typing import Optional
 
 from django.urls import reverse
 
@@ -664,6 +665,11 @@ def test_invalid_bom_item(self):
                 wrong_line = line
                 break
 
+        if not wrong_line:
+            raise self.fail(
+                'No matching BuildLine found for the given stock item'
+            )  # pragma: no cover
+
         data = self.post(
             self.url,
             {
@@ -691,6 +697,11 @@ def test_valid_data(self):
                 right_line = line
                 break
 
+        if not right_line:
+            raise self.fail(
+                'No matching BuildLine found for the given stock item'
+            )  # pragma: no cover
+
         self.post(
             self.url,
             {
@@ -718,11 +729,15 @@ def test_reallocate(self):
         # Find the correct BuildLine
         si = StockItem.objects.get(pk=2)
 
-        right_line = None
+        right_line: Optional[BuildLine] = None
         for line in self.build.build_lines.all():
             if line.bom_item.sub_part.pk == si.part.pk:
-                right_line = line
+                right_line: BuildLine = line
                 break
+        if not right_line:
+            raise self.fail(
+                'No matching BuildLine found for the given stock item'
+            )  # pragma: no cover
 
         self.post(
             self.url,
diff --git a/src/backend/InvenTree/common/api.py b/src/backend/InvenTree/common/api.py
index 6d5027864963..d49809bb7753 100644
--- a/src/backend/InvenTree/common/api.py
+++ b/src/backend/InvenTree/common/api.py
@@ -1,6 +1,7 @@
 """Provides a JSON API for common components."""
 
 import json
+import json.decoder
 
 from django.conf import settings
 from django.contrib.contenttypes.models import ContentType
@@ -13,8 +14,9 @@
 from django.views.decorators.cache import cache_control
 from django.views.decorators.csrf import csrf_exempt
 
+import django_filters.rest_framework.filters as rest_filters
 import django_q.models
-from django_filters import rest_framework as rest_filters
+from django_filters.rest_framework.filterset import FilterSet
 from django_q.tasks import async_task
 from djmoney.contrib.exchange.models import ExchangeBackend, Rate
 from drf_spectacular.utils import OpenApiResponse, extend_schema
@@ -698,7 +700,7 @@ def get(self, request, *args, **kwargs):
         return super().get(request, *args, **kwargs)
 
 
-class AttachmentFilter(rest_filters.FilterSet):
+class AttachmentFilter(FilterSet):
     """Filterset for the AttachmentList API endpoint."""
 
     class Meta:
diff --git a/src/backend/InvenTree/common/currency.py b/src/backend/InvenTree/common/currency.py
index b7749db39c21..d22e0bba82af 100644
--- a/src/backend/InvenTree/common/currency.py
+++ b/src/backend/InvenTree/common/currency.py
@@ -158,7 +158,7 @@ def get_price(
     - If MOQ (minimum order quantity) is required, bump quantity
     - If order multiples are to be observed, then we need to calculate based on that, too
     """
-    from common.currency import currency_code_default
+    # from common.currency import currency_code_default
 
     if hasattr(instance, break_name):
         price_breaks = getattr(instance, break_name).all()
diff --git a/src/backend/InvenTree/common/models.py b/src/backend/InvenTree/common/models.py
index d498a2114397..2d06e68c435d 100644
--- a/src/backend/InvenTree/common/models.py
+++ b/src/backend/InvenTree/common/models.py
@@ -14,7 +14,7 @@
 from enum import Enum
 from io import BytesIO
 from secrets import compare_digest
-from typing import Any, Union
+from typing import Any, Optional, Union
 
 from django.apps import apps
 from django.conf import settings as django_settings
@@ -27,6 +27,7 @@
 from django.core.files.storage import default_storage
 from django.core.validators import MinValueValidator
 from django.db import models, transaction
+from django.db.models import enums
 from django.db.models.signals import post_delete, post_save
 from django.db.utils import IntegrityError, OperationalError, ProgrammingError
 from django.dispatch.dispatcher import receiver
@@ -55,7 +56,7 @@
 logger = structlog.get_logger('inventree')
 
 
-class RenderMeta(models.enums.ChoicesMeta):
+class RenderMeta(enums.ChoicesMeta):
     """Metaclass for rendering choices."""
 
     choice_fnc = None
@@ -916,7 +917,7 @@ def model_name(self) -> str:
 
         return setting.get('model', None)
 
-    def model_filters(self) -> dict:
+    def model_filters(self) -> Optional[dict]:
         """Return the model filters associated with this setting."""
         setting = self.get_setting_definition(
             self.key, **self.get_filters_for_instance()
@@ -1415,8 +1416,8 @@ def save_data(self, payload=None, headers=None, request=None):
             request (optional): Original request object. Defaults to None.
         """
         return WebhookMessage.objects.create(
-            host=request.get_host(),
-            header=json.dumps(dict(headers.items())),
+            host=request.get_host() if request else '',
+            header=json.dumps(dict(headers.items())) if headers else None,
             body=payload,
             endpoint=self,
         )
diff --git a/src/backend/InvenTree/common/notifications.py b/src/backend/InvenTree/common/notifications.py
index 26f1935de8b5..e274269b3126 100644
--- a/src/backend/InvenTree/common/notifications.py
+++ b/src/backend/InvenTree/common/notifications.py
@@ -33,7 +33,9 @@ class NotificationMethod:
     GLOBAL_SETTING = None
     USER_SETTING = None
 
-    def __init__(self, obj: Model, category: str, targets: list, context) -> None:
+    def __init__(
+        self, obj: Model, category: str, targets: Optional[list], context
+    ) -> None:
         """Check that the method is read.
 
         This checks that:
@@ -185,7 +187,7 @@ class MethodStorageClass:
     Is initialized on startup as one instance named `storage` in this file.
     """
 
-    methods_list = None
+    methods_list: list = []
     user_settings = {}
 
     @property
@@ -359,9 +361,7 @@ class InvenTreeNotificationBodies:
     )
 
 
-def trigger_notification(
-    obj: Model, category: Optional[str] = None, obj_ref: str = 'pk', **kwargs
-):
+def trigger_notification(obj: Model, category: str = '', obj_ref: str = 'pk', **kwargs):
     """Send out a notification.
 
     Args:
@@ -419,7 +419,7 @@ def trigger_notification(
         target_exclude = set()
 
     # Collect possible targets
-    if not targets:
+    if not targets and target_fnc:
         targets = target_fnc(*target_args, **target_kwargs)
 
     # Convert list of targets to a list of users
diff --git a/src/backend/InvenTree/common/test_notifications.py b/src/backend/InvenTree/common/test_notifications.py
index b1900342891d..b56b69cbd392 100644
--- a/src/backend/InvenTree/common/test_notifications.py
+++ b/src/backend/InvenTree/common/test_notifications.py
@@ -36,19 +36,19 @@ def send(self):
 
         # no send / send bulk
         with self.assertRaises(NotImplementedError):
-            FalseNotificationMethod('', '', '', '')
+            FalseNotificationMethod('', '', None, '')
 
         # no METHOD_NAME
         with self.assertRaises(NotImplementedError):
-            NoNameNotificationMethod('', '', '', '')
+            NoNameNotificationMethod('', '', None, '')
 
         # a not existent context check
         with self.assertRaises(NotImplementedError):
-            WrongContextNotificationMethod('', '', '', '')
+            WrongContextNotificationMethod('', '', None, '')
 
         # no get_targets
         with self.assertRaises(NotImplementedError):
-            AnotherFalseNotificationMethod('', '', '', {'name': 1, 'message': 2})
+            AnotherFalseNotificationMethod('', '', None, {'name': 1, 'message': 2})
 
     def test_failing_passing(self):
         """Ensure that an error in one deliverymethod is not blocking all mehthods."""
diff --git a/src/backend/InvenTree/common/tests.py b/src/backend/InvenTree/common/tests.py
index dd2d89a0a9b3..b69d56b73a12 100644
--- a/src/backend/InvenTree/common/tests.py
+++ b/src/backend/InvenTree/common/tests.py
@@ -18,7 +18,7 @@
 from django.test.utils import override_settings
 from django.urls import reverse
 
-import PIL
+from PIL import Image
 
 import common.validators
 from common.settings import get_global_setting, set_global_setting
@@ -1298,7 +1298,7 @@ def test_valid_image(self):
         n = NotesImage.objects.count()
 
         # Construct a simple image file
-        image = PIL.Image.new('RGB', (100, 100), color='red')
+        image = Image.new('RGB', (100, 100), color='red')
 
         with io.BytesIO() as output:
             image.save(output, format='PNG')
diff --git a/src/backend/InvenTree/company/api.py b/src/backend/InvenTree/company/api.py
index d4ba2c09907b..e6a1275ce1af 100644
--- a/src/backend/InvenTree/company/api.py
+++ b/src/backend/InvenTree/company/api.py
@@ -4,7 +4,8 @@
 from django.urls import include, path
 from django.utils.translation import gettext_lazy as _
 
-from django_filters import rest_framework as rest_filters
+import django_filters.rest_framework.filters as rest_filters
+from django_filters.rest_framework.filterset import FilterSet
 
 import part.models
 from data_exporter.mixins import DataExportViewMixin
@@ -127,7 +128,7 @@ class AddressDetail(RetrieveUpdateDestroyAPI):
     serializer_class = AddressSerializer
 
 
-class ManufacturerPartFilter(rest_filters.FilterSet):
+class ManufacturerPartFilter(FilterSet):
     """Custom API filters for the ManufacturerPart list endpoint."""
 
     class Meta:
@@ -204,7 +205,7 @@ class ManufacturerPartDetail(RetrieveUpdateDestroyAPI):
     serializer_class = ManufacturerPartSerializer
 
 
-class ManufacturerPartParameterFilter(rest_filters.FilterSet):
+class ManufacturerPartParameterFilter(FilterSet):
     """Custom filterset for the ManufacturerPartParameterList API endpoint."""
 
     class Meta:
@@ -259,7 +260,7 @@ class ManufacturerPartParameterDetail(RetrieveUpdateDestroyAPI):
     serializer_class = ManufacturerPartParameterSerializer
 
 
-class SupplierPartFilter(rest_filters.FilterSet):
+class SupplierPartFilter(FilterSet):
     """API filters for the SupplierPartList endpoint."""
 
     class Meta:
@@ -416,7 +417,7 @@ class SupplierPartDetail(SupplierPartMixin, RetrieveUpdateDestroyAPI):
     """
 
 
-class SupplierPriceBreakFilter(rest_filters.FilterSet):
+class SupplierPriceBreakFilter(FilterSet):
     """Custom API filters for the SupplierPriceBreak list endpoint."""
 
     class Meta:
diff --git a/src/backend/InvenTree/company/migrations/0019_auto_20200413_0642.py b/src/backend/InvenTree/company/migrations/0019_auto_20200413_0642.py
index 3b7c928489e3..0fc852354bcf 100644
--- a/src/backend/InvenTree/company/migrations/0019_auto_20200413_0642.py
+++ b/src/backend/InvenTree/company/migrations/0019_auto_20200413_0642.py
@@ -51,7 +51,7 @@ def reverse_association(apps, schema_editor):  # pragma: no cover
 
         row = cursor.fetchone()
 
-        if len(row) > 0:
+        if row and len(row) > 0:
             try:
                 manufacturer_id = int(row[0])
             except (TypeError, ValueError):
@@ -67,12 +67,12 @@ def reverse_association(apps, schema_editor):  # pragma: no cover
         response = cursor.execute(f"SELECT name from company_company where id={manufacturer_id};")
 
         row = cursor.fetchone()
+        if row:
+            name = row[0]
 
-        name = row[0]
+            print(" - Manufacturer name: '{name}'".format(name=name))
 
-        print(" - Manufacturer name: '{name}'".format(name=name))
-
-        response = cursor.execute("UPDATE part_supplierpart SET manufacturer_name='{name}' WHERE id={ID};".format(name=name, ID=supplier_part_id))
+            response = cursor.execute("UPDATE part_supplierpart SET manufacturer_name='{name}' WHERE id={ID};".format(name=name, ID=supplier_part_id))
 
 def associate_manufacturers(apps, schema_editor):
     """
@@ -106,7 +106,7 @@ def get_manufacturer_name(part_id):
         response = cursor.execute(query)
         row = cursor.fetchone()
 
-        if len(row) > 0:
+        if row and len(row) > 0:
             return row[0]
         return ''  # pragma: no cover
 
@@ -296,11 +296,11 @@ def map_part_to_manufacturer(part_id, idx, total):
 
                 # Double-check if the typed name corresponds to an existing item
                 elif response in companies.keys():
-                    link_part(part, companies[response])
+                    link_part(part_id, companies[response])
                     return
 
                 elif response in links.keys():
-                    link_part(part, links[response])
+                    link_part(part_id, links[response])
                     return
 
                 # No match, create a new manufacturer
diff --git a/src/backend/InvenTree/data_exporter/apps.py b/src/backend/InvenTree/data_exporter/apps.py
index a9eb5d8bbd9d..9cef065b15ae 100644
--- a/src/backend/InvenTree/data_exporter/apps.py
+++ b/src/backend/InvenTree/data_exporter/apps.py
@@ -18,7 +18,7 @@ def ready(self):
     def cleanup(self):
         """Cleanup any old export files."""
         try:
-            from data_exporter.tasks import cleanup_old_export_outputs
+            from data_exporter.tasks import cleanup_old_export_outputs  # type: ignore
 
             cleanup_old_export_outputs()
         except Exception:
diff --git a/src/backend/InvenTree/data_exporter/mixins.py b/src/backend/InvenTree/data_exporter/mixins.py
index 8274e68ee0e3..374599739b53 100644
--- a/src/backend/InvenTree/data_exporter/mixins.py
+++ b/src/backend/InvenTree/data_exporter/mixins.py
@@ -1,6 +1,7 @@
 """Mixin classes for the exporter app."""
 
 from collections import OrderedDict
+from typing import Any
 
 from django.core.exceptions import ValidationError
 from django.core.files.base import ContentFile
@@ -127,7 +128,7 @@ def arrange_export_headers(cls, headers: list) -> list:
         """
         return headers
 
-    def get_nested_value(self, row: dict, key: str) -> any:
+    def get_nested_value(self, row: dict, key: str) -> Any:
         """Get a nested value from a dictionary.
 
         This method allows for dot notation to access nested fields.
diff --git a/src/backend/InvenTree/data_exporter/serializers.py b/src/backend/InvenTree/data_exporter/serializers.py
index d5f90fe48f7a..815f8fe683ec 100644
--- a/src/backend/InvenTree/data_exporter/serializers.py
+++ b/src/backend/InvenTree/data_exporter/serializers.py
@@ -6,7 +6,6 @@
 
 import InvenTree.exceptions
 import InvenTree.helpers
-import InvenTree.serializers
 from plugin import PluginMixinEnum, registry
 
 
@@ -53,7 +52,7 @@ def __init__(self, *args, **kwargs):
             try:
                 supports_export = plugin.supports_export(
                     model_class,
-                    user=request.user,
+                    user=request.user if request else None,
                     serializer_class=serializer_class,
                     view_class=view_class,
                 )
diff --git a/src/backend/InvenTree/generic/states/__init__.py b/src/backend/InvenTree/generic/states/__init__.py
index 90922e9695ba..189150f56113 100644
--- a/src/backend/InvenTree/generic/states/__init__.py
+++ b/src/backend/InvenTree/generic/states/__init__.py
@@ -6,6 +6,7 @@
 States can be extended with custom options for each InvenTree instance - those options are stored in the database and need to link back to state values.
 """
 
+from . import fields
 from .states import ColorEnum, StatusCode, StatusCodeMixin
 from .transition import StateTransitionMixin, TransitionMethod, storage
 
@@ -15,5 +16,6 @@
     'StatusCode',
     'StatusCodeMixin',
     'TransitionMethod',
+    'fields',
     'storage',
 ]
diff --git a/src/backend/InvenTree/generic/states/states.py b/src/backend/InvenTree/generic/states/states.py
index 3304cc3e5c81..a252e9053df9 100644
--- a/src/backend/InvenTree/generic/states/states.py
+++ b/src/backend/InvenTree/generic/states/states.py
@@ -4,6 +4,7 @@
 import logging
 import re
 from enum import Enum
+from typing import Optional
 
 logger = logging.getLogger('inventree')
 
@@ -297,7 +298,7 @@ def get_status(self) -> int:
         """Return the status code for this object."""
         return getattr(self, self.STATUS_FIELD)
 
-    def get_custom_status(self) -> int:
+    def get_custom_status(self) -> Optional[int]:
         """Return the custom status code for this object."""
         return getattr(self, f'{self.STATUS_FIELD}_custom_key', None)
 
diff --git a/src/backend/InvenTree/generic/states/test_transition.py b/src/backend/InvenTree/generic/states/test_transition.py
index 38f4946e32e6..050fa40b9a96 100644
--- a/src/backend/InvenTree/generic/states/test_transition.py
+++ b/src/backend/InvenTree/generic/states/test_transition.py
@@ -58,7 +58,7 @@ def transition(self, *args, **kwargs):
         storage.collect()
 
         # Ensure the class is registered
-        self.assertIn(RaisingImplementation, storage.list)
+        self.assertIn(RaisingImplementation, storage.method_list)
 
         # Ensure stuff is passed to the class
         with self.assertRaises(MyPrivateError) as exp:
@@ -90,8 +90,8 @@ def transition(self, *args, **kwargs):
                     return False  # pragma: no cover # Return false to keep other transitions working
 
         storage.collect()
-        self.assertIn(ValidImplementationNoEffect, storage.list)
-        self.assertIn(ValidImplementation, storage.list)
+        self.assertIn(ValidImplementationNoEffect, storage.method_list)
+        self.assertIn(ValidImplementation, storage.method_list)
 
         # Ensure that the function is called
         self.assertEqual(
diff --git a/src/backend/InvenTree/generic/states/transition.py b/src/backend/InvenTree/generic/states/transition.py
index 6abc7f101025..72b7d68cc192 100644
--- a/src/backend/InvenTree/generic/states/transition.py
+++ b/src/backend/InvenTree/generic/states/transition.py
@@ -1,5 +1,7 @@
 """Classes and functions for plugin controlled object state transitions."""
 
+from typing import Any, Optional
+
 import InvenTree.helpers
 
 
@@ -28,11 +30,11 @@ class TransitionMethodStorageClass:
     Is initialized on startup as one instance named `storage` in this file.
     """
 
-    list = None
+    method_list: Optional[list] = None
 
     def collect(self):
         """Collect all classes in the environment that are transition methods."""
-        filtered_list = {}
+        filtered_list: dict[str, Any] = {}
         for item in InvenTree.helpers.inheritors(TransitionMethod):
             # Try if valid
             try:
@@ -41,11 +43,11 @@ def collect(self):
                 continue
             filtered_list[f'{item.__module__}.{item.__qualname__}'] = item
 
-        self.list = list(filtered_list.values())
+        self.method_list: list = list(filtered_list.values())
 
         # Ensure the list has items
-        if not self.list:
-            self.list = []
+        if not self.method_list:
+            self.method_list = []
 
 
 storage = TransitionMethodStorageClass()
@@ -76,13 +78,15 @@ def handle_transition(
             instance: Object instance
             default_action: Default action to be taken if none of the transitions returns a boolean true value
         """
-        # Check if there is a custom override function for this transition
-        for override in storage.list:
-            rslt = override.transition(
-                current_state, target_state, instance, default_action, **kwargs
-            )
-            if rslt:
-                return rslt
+        list_vals = storage.method_list
+        if list_vals:
+            # Check if there is a custom override function for this transition
+            for override in list_vals:
+                rslt = override.transition(
+                    current_state, target_state, instance, default_action, **kwargs
+                )
+                if rslt:
+                    return rslt
 
         # Default action
         return default_action(current_state, target_state, instance, **kwargs)
diff --git a/src/backend/InvenTree/importer/models.py b/src/backend/InvenTree/importer/models.py
index c634f741cdd9..b7bdcd81bfdc 100644
--- a/src/backend/InvenTree/importer/models.py
+++ b/src/backend/InvenTree/importer/models.py
@@ -294,9 +294,7 @@ def import_data(self) -> None:
             if not any(row_data.values()):
                 continue
 
-            row = importer.models.DataImportRow(
-                session=self, row_data=row_data, row_index=idx
-            )
+            row = DataImportRow(session=self, row_data=row_data, row_index=idx)
 
             row.extract_data(
                 field_mapping=field_mapping,
@@ -308,7 +306,7 @@ def import_data(self) -> None:
             imported_rows.append(row)
 
         # Perform database writes as a single operation
-        importer.models.DataImportRow.objects.bulk_create(imported_rows)
+        DataImportRow.objects.bulk_create(imported_rows)
 
         # Mark the import task as "PROCESSING"
         self.status = DataImportStatusCode.PROCESSING.value
diff --git a/src/backend/InvenTree/importer/operations.py b/src/backend/InvenTree/importer/operations.py
index dcb79e8baad7..0efca9017c59 100644
--- a/src/backend/InvenTree/importer/operations.py
+++ b/src/backend/InvenTree/importer/operations.py
@@ -1,9 +1,12 @@
 """Data import operational functions."""
 
+from typing import Optional
+
 from django.core.exceptions import ValidationError
 from django.utils.translation import gettext_lazy as _
 
 import tablib
+import tablib.core
 
 import InvenTree.helpers
 
@@ -82,7 +85,7 @@ def extract_column_names(data_file) -> list:
     return headers
 
 
-def get_field_label(field) -> str:
+def get_field_label(field) -> Optional[str]:
     """Return the label for a field in a serializer class.
 
     Check for labels in the following order of descending priority:
diff --git a/src/backend/InvenTree/machine/models.py b/src/backend/InvenTree/machine/models.py
index 0e4852c64e47..e08f90550a2a 100755
--- a/src/backend/InvenTree/machine/models.py
+++ b/src/backend/InvenTree/machine/models.py
@@ -1,7 +1,7 @@
 """Models for the machine app."""
 
 import uuid
-from typing import Literal
+from typing import Literal, Optional
 
 from django.contrib import admin
 from django.db import models
@@ -186,7 +186,7 @@ def get_setting_definition(cls, key, **kwargs):
         If not provided, we'll look at the machine registry to see what settings this machine driver requires
         """
         if 'settings' not in kwargs:
-            machine_config: MachineConfig = kwargs.pop('machine_config', None)
+            machine_config: Optional[MachineConfig] = kwargs.pop('machine_config', None)
             if machine_config and machine_config.machine:
                 config_type = kwargs.get('config_type')
                 if config_type == cls.ConfigType.DRIVER:
diff --git a/src/backend/InvenTree/machine/registry.py b/src/backend/InvenTree/machine/registry.py
index af4a61b9928e..aca853039a96 100644
--- a/src/backend/InvenTree/machine/registry.py
+++ b/src/backend/InvenTree/machine/registry.py
@@ -276,7 +276,9 @@ def _calculate_registry_hash(self):
 
         # If the plugin registry has changed, the machine registry hash will change
         plugin_registry.update_plugin_hash()
-        data.update(plugin_registry.registry_hash.encode())
+        current_hash = plugin_registry.registry_hash
+        if current_hash:
+            data.update(current_hash.encode())
 
         for pk, machine in self.machines.items():
             data.update(str(pk).encode())
diff --git a/src/backend/InvenTree/order/api.py b/src/backend/InvenTree/order/api.py
index 283e616cd9ad..87248ac2c05f 100644
--- a/src/backend/InvenTree/order/api.py
+++ b/src/backend/InvenTree/order/api.py
@@ -11,8 +11,9 @@
 from django.urls import include, path, re_path
 from django.utils.translation import gettext_lazy as _
 
+import django_filters.rest_framework.filters as rest_filters
 import rest_framework.serializers
-from django_filters import rest_framework as rest_filters
+from django_filters.rest_framework.filterset import FilterSet
 from django_ical.views import ICalFeed
 from drf_spectacular.types import OpenApiTypes
 from drf_spectacular.utils import extend_schema_field
@@ -97,7 +98,7 @@ def create(self, request, *args, **kwargs):
         )
 
 
-class OrderFilter(rest_filters.FilterSet):
+class OrderFilter(FilterSet):
     """Base class for custom API filters for the OrderList endpoint."""
 
     # Filter against order status
@@ -255,7 +256,7 @@ def filter_max_date(self, queryset, name, value):
         return queryset.filter(q1 | q2 | q3 | q4).distinct()
 
 
-class LineItemFilter(rest_filters.FilterSet):
+class LineItemFilter(FilterSet):
     """Base class for custom API filters for order line item list(s)."""
 
     # Filter by order status
@@ -1087,7 +1088,7 @@ class SalesOrderAllocate(SalesOrderContextMixin, CreateAPI):
     serializer_class = serializers.SalesOrderShipmentAllocationSerializer
 
 
-class SalesOrderAllocationFilter(rest_filters.FilterSet):
+class SalesOrderAllocationFilter(FilterSet):
     """Custom filterset for the SalesOrderAllocationList endpoint."""
 
     class Meta:
@@ -1240,7 +1241,7 @@ class SalesOrderAllocationDetail(SalesOrderAllocationMixin, RetrieveUpdateDestro
     """API endpoint for detali view of a SalesOrderAllocation object."""
 
 
-class SalesOrderShipmentFilter(rest_filters.FilterSet):
+class SalesOrderShipmentFilter(FilterSet):
     """Custom filterset for the SalesOrderShipmentList endpoint."""
 
     class Meta:
diff --git a/src/backend/InvenTree/order/tasks.py b/src/backend/InvenTree/order/tasks.py
index 21babfe2c166..7d315f2b00b4 100644
--- a/src/backend/InvenTree/order/tasks.py
+++ b/src/backend/InvenTree/order/tasks.py
@@ -1,6 +1,7 @@
 """Background tasks for the 'order' app."""
 
 from datetime import datetime, timedelta
+from typing import Union
 
 from django.contrib.auth.models import Group, User
 from django.db import transaction
@@ -99,7 +100,7 @@ def check_overdue_purchase_orders():
 
 def notify_overdue_sales_order(so: order.models.SalesOrder) -> None:
     """Notify appropriate users that a SalesOrder has just become 'overdue'."""
-    targets: list[User, Group, Owner] = []
+    targets: list[Union[User, Group, Owner]] = []
 
     if so.created_by:
         targets.append(so.created_by)
@@ -164,7 +165,7 @@ def check_overdue_sales_orders():
 
 def notify_overdue_return_order(ro: order.models.ReturnOrder) -> None:
     """Notify appropriate users that a ReturnOrder has just become 'overdue'."""
-    targets: list[User, Group, Owner] = []
+    targets: list[Union[User, Group, Owner]] = []
 
     if ro.created_by:
         targets.append(ro.created_by)
diff --git a/src/backend/InvenTree/order/test_api.py b/src/backend/InvenTree/order/test_api.py
index e82a1ac76792..d3ba68ce1358 100644
--- a/src/backend/InvenTree/order/test_api.py
+++ b/src/backend/InvenTree/order/test_api.py
@@ -4,6 +4,7 @@
 import io
 import json
 from datetime import date, datetime, timedelta
+from typing import Optional
 
 from django.core.exceptions import ValidationError
 from django.db import connection
@@ -2036,14 +2037,19 @@ def check_template(line_item):
             return line_item.part.is_template
 
         for line in filter(check_template, self.order.lines.all()):
-            stock_item = None
+            stock_item: Optional[StockItem] = None
 
             # Allocate a matching variant
-            parts = Part.objects.filter(salable=True).filter(variant_of=line.part.pk)
+            parts: list[Part] = Part.objects.filter(salable=True).filter(
+                variant_of=line.part.pk
+            )
             for part in parts:
-                stock_item = part.stock_items.last()
+                stock_item: StockItem = part.stock_items.last()
                 break
 
+            if stock_item is None:
+                raise self.fail('No stock item found for part')  # pragma: no cover
+
             # Fully-allocate each line
             data['items'].append({
                 'line_item': line.pk,
diff --git a/src/backend/InvenTree/part/api.py b/src/backend/InvenTree/part/api.py
index f61f9da261bf..e23fd32f484a 100644
--- a/src/backend/InvenTree/part/api.py
+++ b/src/backend/InvenTree/part/api.py
@@ -8,8 +8,9 @@
 from django.urls import include, path
 from django.utils.translation import gettext_lazy as _
 
-from django_filters import rest_framework as rest_filters
+import django_filters.rest_framework.filters as rest_filters
 from django_filters.rest_framework import DjangoFilterBackend
+from django_filters.rest_framework.filterset import FilterSet
 from drf_spectacular.types import OpenApiTypes
 from drf_spectacular.utils import extend_schema_field
 from rest_framework import serializers
@@ -102,7 +103,7 @@ def get_serializer_context(self):
         return ctx
 
 
-class CategoryFilter(rest_filters.FilterSet):
+class CategoryFilter(FilterSet):
     """Custom filterset class for the PartCategoryList endpoint."""
 
     class Meta:
@@ -286,11 +287,11 @@ def destroy(self, request, *args, **kwargs):
         return super().destroy(
             request,
             *args,
-            **dict(
-                kwargs,
-                delete_parts=delete_parts,
-                delete_child_categories=delete_child_categories,
-            ),
+            **{
+                **kwargs,
+                'delete_parts': delete_parts,
+                'delete_child_categories': delete_child_categories,
+            },
         )
 
 
@@ -403,7 +404,7 @@ class PartInternalPriceList(DataExportViewMixin, ListCreateAPI):
     ordering = 'quantity'
 
 
-class PartTestTemplateFilter(rest_filters.FilterSet):
+class PartTestTemplateFilter(FilterSet):
     """Custom filterset class for the PartTestTemplateList endpoint."""
 
     class Meta:
@@ -891,7 +892,7 @@ def update(self, request, *args, **kwargs):
         return Response({'checksum': part.bom_checksum})
 
 
-class PartFilter(rest_filters.FilterSet):
+class PartFilter(FilterSet):
     """Custom filters for the PartList endpoint.
 
     Uses the django_filters extension framework
@@ -1435,7 +1436,7 @@ def update(self, request, *args, **kwargs):
         return response
 
 
-class PartRelatedFilter(rest_filters.FilterSet):
+class PartRelatedFilter(FilterSet):
     """FilterSet for PartRelated objects."""
 
     class Meta:
@@ -1482,7 +1483,7 @@ class PartRelatedDetail(PartRelatedMixin, RetrieveUpdateDestroyAPI):
     """API endpoint for accessing detail view of a PartRelated object."""
 
 
-class PartParameterTemplateFilter(rest_filters.FilterSet):
+class PartParameterTemplateFilter(FilterSet):
     """FilterSet for PartParameterTemplate objects."""
 
     class Meta:
@@ -1609,7 +1610,7 @@ def get_serializer(self, *args, **kwargs):
         return super().get_serializer(*args, **kwargs)
 
 
-class PartParameterFilter(rest_filters.FilterSet):
+class PartParameterFilter(FilterSet):
     """Custom filters for the PartParameterList API endpoint."""
 
     class Meta:
@@ -1670,7 +1671,7 @@ class PartParameterDetail(PartParameterAPIMixin, RetrieveUpdateDestroyAPI):
     """API endpoint for detail view of a single PartParameter object."""
 
 
-class PartStocktakeFilter(rest_filters.FilterSet):
+class PartStocktakeFilter(FilterSet):
     """Custom filter for the PartStocktakeList endpoint."""
 
     class Meta:
@@ -1753,7 +1754,7 @@ def get_serializer_context(self):
         return context
 
 
-class BomFilter(rest_filters.FilterSet):
+class BomFilter(FilterSet):
     """Custom filters for the BOM list."""
 
     class Meta:
diff --git a/src/backend/InvenTree/part/models.py b/src/backend/InvenTree/part/models.py
index 81f673daca28..cb0b738e5569 100644
--- a/src/backend/InvenTree/part/models.py
+++ b/src/backend/InvenTree/part/models.py
@@ -807,7 +807,7 @@ def validate_serial_number(
         if not check_duplicates:
             return
 
-        from part.models import Part
+        # from part.models import Part
         from stock.models import StockItem
 
         if get_global_setting('SERIAL_NUMBER_GLOBALLY_UNIQUE', False):
@@ -838,7 +838,7 @@ def validate_serial_number(
 
     def find_conflicting_serial_numbers(self, serials: list) -> list:
         """For a provided list of serials, return a list of those which are conflicting."""
-        from part.models import Part
+        # from part.models import Part
         from stock.models import StockItem
 
         conflicts = []
diff --git a/src/backend/InvenTree/part/stocktake.py b/src/backend/InvenTree/part/stocktake.py
index 4878265f8fe9..97f307cdc585 100644
--- a/src/backend/InvenTree/part/stocktake.py
+++ b/src/backend/InvenTree/part/stocktake.py
@@ -14,6 +14,7 @@
 
 import common.currency
 import common.models
+import common.notifications
 import InvenTree.helpers
 import part.models
 import stock.models
diff --git a/src/backend/InvenTree/part/test_api.py b/src/backend/InvenTree/part/test_api.py
index 4d8af0584645..d4b22940c12e 100644
--- a/src/backend/InvenTree/part/test_api.py
+++ b/src/backend/InvenTree/part/test_api.py
@@ -11,7 +11,7 @@
 from django.test.utils import CaptureQueriesContext
 from django.urls import reverse
 
-import PIL
+from PIL import Image
 from rest_framework.test import APIClient
 
 import build.models
@@ -66,7 +66,7 @@ def create_test_image(self):
 
         fn = BASE_DIR / '_testfolder' / 'part_image_123abc.png'
 
-        img = PIL.Image.new('RGB', (128, 128), color='blue')
+        img = Image.new('RGB', (128, 128), color='blue')
         img.save(fn)
 
         with open(fn, 'rb') as img_file:
@@ -1694,7 +1694,7 @@ def test_image_upload(self):
         for fmt in ['jpg', 'j2k', 'png', 'bmp', 'webp']:
             fn = f'{test_path}.{fmt}'
 
-            img = PIL.Image.new('RGB', (128, 128), color='red')
+            img = Image.new('RGB', (128, 128), color='red')
             img.save(fn)
 
             with open(fn, 'rb') as dummy_image:
@@ -1744,7 +1744,7 @@ def test_update_existing_image(self):
 
         fn = BASE_DIR / '_testfolder' / 'part_image_123abc.png'
 
-        img = PIL.Image.new('RGB', (128, 128), color='blue')
+        img = Image.new('RGB', (128, 128), color='blue')
         img.save(fn)
 
         # Upload the image to a part
diff --git a/src/backend/InvenTree/plugin/admin.py b/src/backend/InvenTree/plugin/admin.py
index 49afa1aed611..5584e11ac0dd 100644
--- a/src/backend/InvenTree/plugin/admin.py
+++ b/src/backend/InvenTree/plugin/admin.py
@@ -2,8 +2,8 @@
 
 from django.contrib import admin
 
-import plugin.registry as pl_registry
 from plugin import models
+from plugin.registry import registry as pl_registry
 
 
 def plugin_update(queryset, new_status: bool):
diff --git a/src/backend/InvenTree/plugin/api.py b/src/backend/InvenTree/plugin/api.py
index dacd6e2ac8c9..b7fbcbe34853 100644
--- a/src/backend/InvenTree/plugin/api.py
+++ b/src/backend/InvenTree/plugin/api.py
@@ -6,8 +6,9 @@
 from django.urls import include, path, re_path
 from django.utils.translation import gettext_lazy as _
 
-from django_filters import rest_framework as rest_filters
+import django_filters.rest_framework.filters as rest_filters
 from django_filters.rest_framework import DjangoFilterBackend
+from django_filters.rest_framework.filterset import FilterSet
 from drf_spectacular.utils import extend_schema
 from rest_framework import status
 from rest_framework.exceptions import NotFound
@@ -36,7 +37,7 @@
 from plugin.registry import registry
 
 
-class PluginFilter(rest_filters.FilterSet):
+class PluginFilter(FilterSet):
     """Filter for the PluginConfig model.
 
     Provides custom filtering options for the FilterList API endpoint.
diff --git a/src/backend/InvenTree/plugin/base/barcodes/api.py b/src/backend/InvenTree/plugin/base/barcodes/api.py
index 301667c50904..579b9abddf51 100644
--- a/src/backend/InvenTree/plugin/base/barcodes/api.py
+++ b/src/backend/InvenTree/plugin/base/barcodes/api.py
@@ -5,7 +5,7 @@
 from django.utils.translation import gettext_lazy as _
 
 import structlog
-from django_filters import rest_framework as rest_filters
+from django_filters.rest_framework.filterset import FilterSet
 from drf_spectacular.utils import extend_schema, extend_schema_view
 from rest_framework import status
 from rest_framework.exceptions import PermissionDenied, ValidationError
@@ -770,7 +770,7 @@ def get_queryset(self):
         return queryset
 
 
-class BarcodeScanResultFilter(rest_filters.FilterSet):
+class BarcodeScanResultFilter(FilterSet):
     """Custom filterset for the BarcodeScanResult API."""
 
     class Meta:
diff --git a/src/backend/InvenTree/plugin/base/barcodes/mixins.py b/src/backend/InvenTree/plugin/base/barcodes/mixins.py
index 848f55258544..f60b735c67bc 100644
--- a/src/backend/InvenTree/plugin/base/barcodes/mixins.py
+++ b/src/backend/InvenTree/plugin/base/barcodes/mixins.py
@@ -2,6 +2,8 @@
 
 from __future__ import annotations
 
+from typing import Optional
+
 from django.core.exceptions import ValidationError
 from django.db.models import Q
 from django.utils.translation import gettext_lazy as _
@@ -113,7 +115,7 @@ def get_field_value(self, key, backup_value=None):
 
         return fields.get(key, backup_value)
 
-    def get_part(self) -> Part | None:
+    def get_part(self) -> Optional[Part]:
         """Extract the Part object from the barcode fields."""
         # TODO: Implement this
         return None
@@ -128,7 +130,7 @@ def supplier_part_number(self):
         """Return the supplier part number from the barcode fields."""
         return self.get_field_value(self.SUPPLIER_PART_NUMBER)
 
-    def get_supplier_part(self) -> SupplierPart | None:
+    def get_supplier_part(self) -> Optional[SupplierPart]:
         """Return the SupplierPart object for the scanned barcode.
 
         Returns:
@@ -172,7 +174,7 @@ def manufacturer_part_number(self):
         """Return the manufacturer part number from the barcode fields."""
         return self.get_field_value(self.MANUFACTURER_PART_NUMBER)
 
-    def get_manufacturer_part(self) -> ManufacturerPart | None:
+    def get_manufacturer_part(self) -> Optional[ManufacturerPart]:
         """Return the ManufacturerPart object for the scanned barcode.
 
         Returns:
@@ -213,7 +215,7 @@ def supplier_order_number(self):
         """Return the supplier order number from the barcode fields."""
         return self.get_field_value(self.SUPPLIER_ORDER_NUMBER)
 
-    def get_purchase_order(self) -> PurchaseOrder | None:
+    def get_purchase_order(self) -> Optional[PurchaseOrder]:
         """Extract the PurchaseOrder object from the barcode fields.
 
         Inspect the customer_order_number and supplier_order_number fields,
@@ -260,7 +262,7 @@ def extract_barcode_fields(self, barcode_data: str) -> dict[str, str]:
             'extract_barcode_fields must be implemented by each plugin'
         )
 
-    def scan(self, barcode_data: str) -> dict:
+    def scan(self, barcode_data: str) -> Optional[dict]:
         """Perform a generic 'scan' operation on a supplier barcode.
 
         The supplier barcode may provide sufficient information to match against
@@ -319,7 +321,7 @@ def scan_receive_item(
         location=None,
         auto_allocate: bool = True,
         **kwargs,
-    ) -> dict | None:
+    ) -> Optional[dict]:
         """Attempt to receive an item against a PurchaseOrder via barcode scanning.
 
         Arguments:
@@ -430,7 +432,7 @@ def scan_receive_item(
 
         return response
 
-    def get_supplier(self, cache: bool = False) -> Company | None:
+    def get_supplier(self, cache: bool = False) -> Optional[Company]:
         """Get the supplier for the SUPPLIER_ID set in the plugin settings.
 
         If it's not defined, try to guess it and set it if possible.
diff --git a/src/backend/InvenTree/plugin/base/integration/APICallMixin.py b/src/backend/InvenTree/plugin/base/integration/APICallMixin.py
index d67bc64857b2..85cd21825f83 100644
--- a/src/backend/InvenTree/plugin/base/integration/APICallMixin.py
+++ b/src/backend/InvenTree/plugin/base/integration/APICallMixin.py
@@ -163,7 +163,8 @@ def api_call(
             url = f'{self.api_url}/{endpoint}'
 
         # build kwargs for call
-        kwargs.update({'url': url, 'headers': headers})
+        kwargs.update({'headers': headers})
+        kwargs.pop('url', None)
 
         if data and json:
             raise ValueError('You can either pass `data` or `json` to this function.')
@@ -175,7 +176,7 @@ def api_call(
             kwargs['data'] = data
 
         # run command
-        response = requests.request(method, **kwargs)
+        response = requests.request(method, url=url, **kwargs)
 
         # return
         if simple_response:
diff --git a/src/backend/InvenTree/plugin/base/integration/DataExport.py b/src/backend/InvenTree/plugin/base/integration/DataExport.py
index 6d1eadb6e185..603f5d234d75 100644
--- a/src/backend/InvenTree/plugin/base/integration/DataExport.py
+++ b/src/backend/InvenTree/plugin/base/integration/DataExport.py
@@ -1,7 +1,7 @@
 """Plugin class for custom data exporting."""
 
 from collections import OrderedDict
-from typing import Union
+from typing import Optional, Union
 
 from django.contrib.auth.models import User
 from django.db.models import QuerySet
@@ -36,8 +36,8 @@ def supports_export(
         self,
         model_class: type,
         user: User,
-        serializer_class: serializers.Serializer = None,
-        view_class: views.APIView = None,
+        serializer_class: Optional[serializers.Serializer] = None,
+        view_class: Optional[views.APIView] = None,
         *args,
         **kwargs,
     ) -> bool:
diff --git a/src/backend/InvenTree/plugin/base/integration/ValidationMixin.py b/src/backend/InvenTree/plugin/base/integration/ValidationMixin.py
index 341696bf6258..0678bb3260b8 100644
--- a/src/backend/InvenTree/plugin/base/integration/ValidationMixin.py
+++ b/src/backend/InvenTree/plugin/base/integration/ValidationMixin.py
@@ -72,7 +72,7 @@ def validate_model_deletion(self, instance: Model) -> None:
 
     def validate_model_instance(
         self, instance: Model, deltas: Optional[dict] = None
-    ) -> None:
+    ) -> Optional[bool]:
         """Run custom validation on a database model instance.
 
         This method is called when a model instance is being validated.
@@ -90,7 +90,7 @@ def validate_model_instance(
         """
         return None
 
-    def validate_part_name(self, name: str, part: part.models.Part) -> None:
+    def validate_part_name(self, name: str, part: part.models.Part) -> Optional[bool]:
         """Perform validation on a proposed Part name.
 
         Arguments:
@@ -105,7 +105,7 @@ def validate_part_name(self, name: str, part: part.models.Part) -> None:
         """
         return None
 
-    def validate_part_ipn(self, ipn: str, part: part.models.Part) -> None:
+    def validate_part_ipn(self, ipn: str, part: part.models.Part) -> Optional[bool]:
         """Perform validation on a proposed Part IPN (internal part number).
 
         Arguments:
@@ -122,7 +122,7 @@ def validate_part_ipn(self, ipn: str, part: part.models.Part) -> None:
 
     def validate_batch_code(
         self, batch_code: str, item: stock.models.StockItem
-    ) -> None:
+    ) -> Optional[bool]:
         """Validate the supplied batch code.
 
         Arguments:
@@ -137,7 +137,7 @@ def validate_batch_code(
         """
         return None
 
-    def generate_batch_code(self, **kwargs) -> str:
+    def generate_batch_code(self, **kwargs) -> Optional[str]:
         """Generate a new batch code.
 
         This method is called when a new batch code is required.
@@ -154,8 +154,8 @@ def validate_serial_number(
         self,
         serial: str,
         part: part.models.Part,
-        stock_item: stock.models.StockItem = None,
-    ) -> None:
+        stock_item: Optional[stock.models.StockItem] = None,
+    ) -> Optional[bool]:
         """Validate the supplied serial number.
 
         Arguments:
@@ -171,7 +171,7 @@ def validate_serial_number(
         """
         return None
 
-    def convert_serial_to_int(self, serial: str) -> int:
+    def convert_serial_to_int(self, serial: str) -> Optional[int]:
         """Convert a serial number (string) into an integer representation.
 
         This integer value is used for efficient sorting based on serial numbers.
@@ -192,7 +192,7 @@ def convert_serial_to_int(self, serial: str) -> int:
         """
         return None
 
-    def get_latest_serial_number(self, part, **kwargs):
+    def get_latest_serial_number(self, part, **kwargs) -> Optional[str]:
         """Return the 'latest' serial number for a given Part instance.
 
         A plugin which implements this method can either return:
@@ -209,8 +209,8 @@ def get_latest_serial_number(self, part, **kwargs):
         return None
 
     def increment_serial_number(
-        self, serial: str, part: part.models.Part = None, **kwargs
-    ) -> str:
+        self, serial: str, part: Optional[part.models.Part] = None, **kwargs
+    ) -> Optional[str]:
         """Return the next sequential serial based on the provided value.
 
         A plugin which implements this method can either return:
@@ -229,7 +229,7 @@ def increment_serial_number(
 
     def validate_part_parameter(
         self, parameter: part.models.PartParameter, data: str
-    ) -> None:
+    ) -> Optional[bool]:
         """Validate a parameter value.
 
         Arguments:
diff --git a/src/backend/InvenTree/plugin/broken/broken_file.py b/src/backend/InvenTree/plugin/broken/broken_file.py
index f56932e876c4..83437025cf47 100644
--- a/src/backend/InvenTree/plugin/broken/broken_file.py
+++ b/src/backend/InvenTree/plugin/broken/broken_file.py
@@ -7,4 +7,4 @@ class BrokenFileIntegrationPlugin(InvenTreePlugin):
     """An very broken plugin."""
 
 
-aaa = bb  # noqa: F821
+aaa = bb  # noqa: F821  # type: ignore[unresolved-reference]
diff --git a/src/backend/InvenTree/plugin/builtin/exporter/bom_exporter.py b/src/backend/InvenTree/plugin/builtin/exporter/bom_exporter.py
index d5fbc385bdc4..5a4f906c57b1 100644
--- a/src/backend/InvenTree/plugin/builtin/exporter/bom_exporter.py
+++ b/src/backend/InvenTree/plugin/builtin/exporter/bom_exporter.py
@@ -1,5 +1,7 @@
 """Multi-level BOM exporter plugin."""
 
+from typing import Optional
+
 from django.utils.translation import gettext_lazy as _
 
 import rest_framework.serializers as serializers
@@ -179,7 +181,7 @@ def export_data(
 
         return self.bom_data
 
-    def process_bom_row(self, bom_item, level, **kwargs) -> list:
+    def process_bom_row(self, bom_item, level, **kwargs) -> Optional[list]:
         """Process a single BOM row.
 
         Arguments:
diff --git a/src/backend/InvenTree/plugin/helpers.py b/src/backend/InvenTree/plugin/helpers.py
index d3f45c4a1921..ddb0bf722f17 100644
--- a/src/backend/InvenTree/plugin/helpers.py
+++ b/src/backend/InvenTree/plugin/helpers.py
@@ -51,7 +51,7 @@ class MixinNotImplementedError(NotImplementedError):
 
 def log_error(error, reference: str = 'general'):
     """Log an plugin error."""
-    from plugin import registry
+    from plugin.registry import registry
 
     # make sure the registry is set up
     if reference not in registry.errors:
diff --git a/src/backend/InvenTree/plugin/models.py b/src/backend/InvenTree/plugin/models.py
index c5947c24f519..4e40213b9a7e 100644
--- a/src/backend/InvenTree/plugin/models.py
+++ b/src/backend/InvenTree/plugin/models.py
@@ -2,6 +2,7 @@
 
 import inspect
 import warnings
+from typing import Optional
 
 from django.conf import settings
 from django.contrib import admin
@@ -195,7 +196,7 @@ def is_package(self) -> bool:
         return getattr(self.plugin, 'is_package', False)
 
     @property
-    def admin_source(self) -> str:
+    def admin_source(self) -> Optional[str]:
         """Return the path to the javascript file which renders custom admin content for this plugin.
 
         - It is required that the file provides a 'renderPluginSettings' function!
@@ -215,7 +216,7 @@ def admin_source(self) -> str:
         return None
 
     @property
-    def admin_context(self) -> dict:
+    def admin_context(self) -> Optional[dict]:
         """Return the context data for the admin integration."""
         if not self.plugin:
             return None
diff --git a/src/backend/InvenTree/plugin/plugin.py b/src/backend/InvenTree/plugin/plugin.py
index 2ba7de00b962..6aeb43c2c4a5 100644
--- a/src/backend/InvenTree/plugin/plugin.py
+++ b/src/backend/InvenTree/plugin/plugin.py
@@ -4,7 +4,7 @@
 import inspect
 import warnings
 from datetime import datetime
-from distutils.sysconfig import get_python_lib
+from distutils.sysconfig import get_python_lib  # type: ignore[import]
 from importlib.metadata import PackageNotFoundError, metadata
 from pathlib import Path
 from typing import Optional, Union
@@ -468,8 +468,9 @@ def define_package(self):
             package = {}
 
         # process date
-        if package.get('date'):
-            package['date'] = datetime.fromisoformat(package.get('date'))
+        date = package.get('date')
+        if date:
+            package['date'] = datetime.fromisoformat(date)
 
         # set variables
         self.package = package
@@ -489,7 +490,7 @@ def plugin_static_file(self, *args):
 
         return url
 
-    def get_admin_source(self) -> str:
+    def get_admin_source(self) -> Union[str, None]:
         """Return a path to a JavaScript file which contains custom UI settings.
 
         The frontend code expects that this file provides a function named 'renderPluginSettings'.
@@ -499,7 +500,7 @@ def get_admin_source(self) -> str:
 
         return self.plugin_static_file(self.ADMIN_SOURCE)
 
-    def get_admin_context(self) -> dict:
+    def get_admin_context(self) -> Union[dict, None]:
         """Return a context dictionary for the admin panel settings.
 
         This is an optional method which can be overridden by the plugin.
diff --git a/src/backend/InvenTree/plugin/registry.py b/src/backend/InvenTree/plugin/registry.py
index 63ba3f4bdc47..92bca831c807 100644
--- a/src/backend/InvenTree/plugin/registry.py
+++ b/src/backend/InvenTree/plugin/registry.py
@@ -84,12 +84,12 @@ def __init__(self) -> None:
         ] = {}  # List of all plugin instances
 
         # Keep an internal hash of the plugin registry state
-        self.registry_hash = None
+        self.registry_hash: Optional[str] = None
 
         self.plugin_modules: list[InvenTreePlugin] = []  # Holds all discovered plugins
         self.mixin_modules: dict[str, Any] = {}  # Holds all discovered mixins
 
-        self.errors = {}  # Holds discovering errors
+        self.errors: dict[str, list[Any]] = {}  # Holds discovering errors
 
         self.loading_lock = Lock()  # Lock to prevent multiple loading at the same time
 
@@ -220,7 +220,7 @@ def call_plugin_function(self, slug: str, func: str, *args, **kwargs):
 
     # region registry functions
     def with_mixin(
-        self, mixin: str, active: bool = True, builtin: Optional[bool] = None
+        self, mixin: str, active: Optional[bool] = True, builtin: Optional[bool] = None
     ) -> list:
         """Returns reference to all plugins that have a specified mixin enabled.
 
@@ -538,10 +538,9 @@ def safe_reference(plugin, key: str, active: bool = True):
             package_name = getattr(plugin, 'package_name', None)
 
         # Auto-enable default builtin plugins
-        if builtin and plg_db and plg_db.is_mandatory():
-            if not plg_db.active:
-                plg_db.active = True
-                plg_db.save()
+        if builtin and plg_db and plg_db.is_mandatory() and not plg_db.active:
+            plg_db.active = True
+            plg_db.save()
 
         # Save the package_name attribute to the plugin
         if plg_db.package_name != package_name:
@@ -611,9 +610,9 @@ def safe_reference(plugin, key: str, active: bool = True):
                     f"Plugin '{p}' is not compatible with the current InvenTree version {v}"
                 )
                 if v := plg_i.MIN_VERSION:
-                    _msg += _(f'Plugin requires at least version {v}')
+                    _msg += _(f'Plugin requires at least version {v}')  # type: ignore[unsupported-operator]
                 if v := plg_i.MAX_VERSION:
-                    _msg += _(f'Plugin requires at most version {v}')
+                    _msg += _(f'Plugin requires at most version {v}')  # type: ignore[unsupported-operator]
                 # Log to error stack
                 log_error(_msg, reference='init')
             else:
@@ -656,7 +655,7 @@ def _init_plugins(self):
 
                         logger.exception(
                             '[PLUGIN] Encountered an error with %s:\n%s',
-                            error.path,
+                            getattr(error, 'path', None),
                             str(error),
                         )
 
@@ -929,11 +928,14 @@ def _load_source(modname, filename):
 
     # loader = importlib.machinery.SourceFileLoader(modname, filename)
     spec = importlib.util.spec_from_file_location(modname, filename)  # , loader=loader)
+    if spec is None:
+        raise ImportError(f"Cannot find module '{modname}'")  # pragma: no cover
     module = importlib.util.module_from_spec(spec)
 
     sys.modules[module.__name__] = module
 
-    if spec.loader:
-        spec.loader.exec_module(module)
+    loader = spec.loader
+    if loader is not None:
+        loader.exec_module(module)
 
     return module
diff --git a/src/backend/InvenTree/plugin/test_plugin.py b/src/backend/InvenTree/plugin/test_plugin.py
index e7eb2aea2f5d..bee0d6ba2976 100644
--- a/src/backend/InvenTree/plugin/test_plugin.py
+++ b/src/backend/InvenTree/plugin/test_plugin.py
@@ -7,6 +7,7 @@
 import textwrap
 from datetime import datetime
 from pathlib import Path
+from typing import Optional
 from unittest import mock
 from unittest.mock import patch
 
@@ -14,7 +15,8 @@
 from django.test import TestCase, override_settings
 
 import plugin.templatetags.plugin_extras as plugin_tags
-from plugin import InvenTreePlugin, registry
+from plugin import InvenTreePlugin
+from plugin.registry import registry
 from plugin.samples.integration.another_sample import (
     NoIntegrationPlugin,
     WrongIntegrationPlugin,
@@ -201,7 +203,9 @@ def test_version(self):
         self.assertFalse(self.plugin_version.check_version([0, 1, 4]))
 
         plug = registry.plugins_full.get('sampleversion')
-        self.assertEqual(plug.is_active(), False)
+        self.assertIsNotNone(plug)
+        if plug:
+            self.assertEqual(plug.is_active(), False)
 
 
 class RegistryTests(TestCase):
@@ -247,7 +251,7 @@ def test_subfolder_loading(self):
     def test_folder_loading(self):
         """Test that plugins in folders outside of BASE_DIR get loaded."""
         # Run in temporary directory -> always a new random name
-        with tempfile.TemporaryDirectory() as tmp:
+        with tempfile.TemporaryDirectory() as tmp:  # type: ignore[no-matching-overload]
             # Fill directory with sample data
             new_dir = Path(tmp).joinpath('mock')
             shutil.copytree(self.mockDir(), new_dir)
@@ -285,14 +289,15 @@ def test_broken_samples(self):
         # There should be at least one discovery error in the module `broken_file`
         self.assertGreater(len(registry.errors.get('discovery')), 0)
         self.assertEqual(
-            registry.errors.get('discovery')[0]['broken_file'],
+            registry.errors.get('discovery')[0]['broken_file'],  # type: ignore[call-possibly-unbound-method]
             "name 'bb' is not defined",
         )
 
         # There should be at least one load error with an intentional KeyError
         self.assertGreater(len(registry.errors.get('init')), 0)
         self.assertEqual(
-            registry.errors.get('init')[0]['broken_sample'], "'This is a dummy error'"
+            registry.errors.get('init')[0]['broken_sample'],  # type: ignore[call-possibly-unbound-method]
+            "'This is a dummy error'",
         )
 
     @override_settings(PLUGIN_TESTING=True, PLUGIN_TESTING_SETUP=True)
@@ -337,7 +342,7 @@ class DummyCIPlugin(InvenTreePlugin):
 
         def create_plugin_file(
             version: str, enabled: bool = True, reload: bool = True
-        ) -> str:
+        ) -> Optional[str]:
             """Create a plugin file with the given version.
 
             Arguments:
diff --git a/src/backend/InvenTree/report/api.py b/src/backend/InvenTree/report/api.py
index b873cde37f69..77adf2f80784 100644
--- a/src/backend/InvenTree/report/api.py
+++ b/src/backend/InvenTree/report/api.py
@@ -6,8 +6,9 @@
 from django.utils.translation import gettext_lazy as _
 from django.views.decorators.cache import never_cache
 
-from django_filters import rest_framework as rest_filters
+import django_filters.rest_framework.filters as rest_filters
 from django_filters.rest_framework import DjangoFilterBackend
+from django_filters.rest_framework.filterset import FilterSet
 from rest_framework.generics import GenericAPIView
 from rest_framework.response import Response
 
@@ -32,7 +33,7 @@ class TemplatePermissionMixin:
     permission_classes = [InvenTree.permissions.IsStaffOrReadOnlyScope]
 
 
-class ReportFilterBase(rest_filters.FilterSet):
+class ReportFilterBase(FilterSet):
     """Base filter class for label and report templates."""
 
     enabled = rest_filters.BooleanFilter()
diff --git a/src/backend/InvenTree/report/apps.py b/src/backend/InvenTree/report/apps.py
index cf7d679ffd92..c227a6e50935 100644
--- a/src/backend/InvenTree/report/apps.py
+++ b/src/backend/InvenTree/report/apps.py
@@ -67,7 +67,7 @@ def ready(self):
     def cleanup(self):
         """Cleanup old label and report outputs."""
         try:
-            from report.tasks import cleanup_old_report_outputs
+            from report.tasks import cleanup_old_report_outputs  # type: ignore[import]
 
             cleanup_old_report_outputs()
         except Exception:
diff --git a/src/backend/InvenTree/report/models.py b/src/backend/InvenTree/report/models.py
index 8cc046c91d5d..1bc97ab5d3fb 100644
--- a/src/backend/InvenTree/report/models.py
+++ b/src/backend/InvenTree/report/models.py
@@ -225,7 +225,7 @@ def save(self, *args, **kwargs):
         ),
     )
 
-    def generate_filename(self, context, **kwargs):
+    def generate_filename(self, context, **kwargs) -> str:
         """Generate a filename for this report."""
         template_string = Template(self.filename_pattern)
 
@@ -391,7 +391,8 @@ def get_report_size(self) -> str:
     def get_context(self, instance, request=None, **kwargs):
         """Supply context data to the report template for rendering."""
         base_context = super().get_context(instance, request)
-        report_context: ReportContextExtension = {
+
+        report_context: ReportContextExtension = {  # type: ignore[invalid-assignment]
             'page_size': self.get_report_size(),
             'landscape': self.landscape,
         }
@@ -438,7 +439,7 @@ def print(self, items: list, request=None, output=None, **kwargs) -> DataOutput:
         debug_mode = get_global_setting('REPORT_DEBUG_MODE', False)
 
         # Start with a default report name
-        report_name = None
+        report_name: Optional[str] = None
 
         report_plugins = registry.with_mixin(PluginMixinEnum.REPORT)
 
@@ -513,6 +514,9 @@ def print(self, items: list, request=None, output=None, **kwargs) -> DataOutput:
                 'path': request.path if request else None,
             })
 
+        if not report_name:
+            report_name = ''  # pragma: no cover
+
         if not report_name.endswith('.pdf'):
             report_name += '.pdf'
 
@@ -541,7 +545,8 @@ def print(self, items: list, request=None, output=None, **kwargs) -> DataOutput:
 
         # Save the generated report to the database
         output.complete = True
-        output.output = ContentFile(data, report_name)
+        if data:
+            output.output = ContentFile(data, report_name)
         output.save()
 
         return output
@@ -598,7 +603,7 @@ def generate_page_style(self, **kwargs):
     def get_context(self, instance, request=None, **kwargs):
         """Supply context data to the label template for rendering."""
         base_context = super().get_context(instance, request, **kwargs)
-        label_context: LabelContextExtension = {
+        label_context: LabelContextExtension = {  # type: ignore[invalid-assignment]
             'width': self.width,
             'height': self.height,
             'page_style': None,
diff --git a/src/backend/InvenTree/report/templatetags/barcode.py b/src/backend/InvenTree/report/templatetags/barcode.py
index 75237bbd7a56..9a87adb3b3fe 100644
--- a/src/backend/InvenTree/report/templatetags/barcode.py
+++ b/src/backend/InvenTree/report/templatetags/barcode.py
@@ -4,6 +4,7 @@
 from django.utils.safestring import mark_safe
 
 import barcode as python_barcode
+import barcode.writer as python_barcode_writer
 import qrcode.constants as ECL
 from PIL import Image, ImageColor
 from qrcode.main import QRCode
@@ -122,7 +123,7 @@ def barcode(data: str, barcode_class='code128', **kwargs) -> str:
 
     data = str(data).zfill(constructor.digits)
 
-    writer = python_barcode.writer.ImageWriter
+    writer = python_barcode_writer.ImageWriter
 
     barcode_image = constructor(data, writer=writer())
 
@@ -148,7 +149,7 @@ def datamatrix(data: str, **kwargs) -> str:
     Returns:
         image (str): base64 encoded image data
     """
-    from ppf.datamatrix import DataMatrix
+    from ppf.datamatrix.datamatrix import DataMatrix
 
     data = str(data).strip()
 
diff --git a/src/backend/InvenTree/report/templatetags/report.py b/src/backend/InvenTree/report/templatetags/report.py
index ed6b5c3da801..5c7973730212 100644
--- a/src/backend/InvenTree/report/templatetags/report.py
+++ b/src/backend/InvenTree/report/templatetags/report.py
@@ -50,7 +50,7 @@ def filter_queryset(queryset: QuerySet, **kwargs) -> QuerySet:
 
 
 @register.simple_tag()
-def filter_db_model(model_name: str, **kwargs) -> QuerySet:
+def filter_db_model(model_name: str, **kwargs) -> Optional[QuerySet]:
     """Filter a database model based on the provided keyword arguments.
 
     Arguments:
@@ -102,7 +102,7 @@ def getindex(container: list, index: int) -> Any:
 
 
 @register.simple_tag()
-def getkey(container: dict, key: str, backup_value: Optional[any] = None) -> Any:
+def getkey(container: dict, key: str, backup_value: Optional[Any] = None) -> Any:
     """Perform key lookup in the provided dict object.
 
     This function is provided to get around template rendering limitations.
@@ -301,14 +301,13 @@ def part_image(part: Part, preview: bool = False, thumbnail: bool = False, **kwa
     if type(part) is not Part:
         raise TypeError(_('part_image tag requires a Part instance'))
 
-    if not part.image:
+    part_img = part.image
+    if not part_img:
         img = None
     elif preview:
-        img = None if not hasattr(part.image, 'preview') else part.image.preview.name
+        img = None if not hasattr(part.image, 'preview') else part_img.preview.name
     elif thumbnail:
-        img = (
-            None if not hasattr(part.image, 'thumbnail') else part.image.thumbnail.name
-        )
+        img = None if not hasattr(part.image, 'thumbnail') else part_img.thumbnail.name
     else:
         img = part.image.name
 
@@ -316,7 +315,7 @@ def part_image(part: Part, preview: bool = False, thumbnail: bool = False, **kwa
 
 
 @register.simple_tag()
-def part_parameter(part: Part, parameter_name: str) -> str:
+def part_parameter(part: Part, parameter_name: str) -> Optional[str]:
     """Return a PartParameter object for the given part and parameter name.
 
     Arguments:
@@ -348,12 +347,15 @@ def company_image(
     if type(company) is not Company:
         raise TypeError(_('company_image tag requires a Company instance'))
 
-    if preview:
-        img = company.image.preview.name
+    cmp_img = company.image
+    if not cmp_img:
+        img = None
+    elif preview:
+        img = cmp_img.preview.name
     elif thumbnail:
-        img = company.image.thumbnail.name
+        img = cmp_img.thumbnail.name
     else:
-        img = company.image.name
+        img = cmp_img.name
 
     return uploaded_image(img, **kwargs)
 
diff --git a/src/backend/InvenTree/stock/api.py b/src/backend/InvenTree/stock/api.py
index 81c9bea06d99..5544ecbfb237 100644
--- a/src/backend/InvenTree/stock/api.py
+++ b/src/backend/InvenTree/stock/api.py
@@ -9,7 +9,8 @@
 from django.urls import include, path
 from django.utils.translation import gettext_lazy as _
 
-from django_filters import rest_framework as rest_filters
+import django_filters.rest_framework.filters as rest_filters
+from django_filters.rest_framework.filterset import FilterSet
 from drf_spectacular.types import OpenApiTypes
 from drf_spectacular.utils import extend_schema_field
 from rest_framework import status
@@ -228,7 +229,7 @@ def get_serializer_context(self):
         return ctx
 
 
-class StockLocationFilter(rest_filters.FilterSet):
+class StockLocationFilter(FilterSet):
     """Base class for custom API filters for the StockLocation endpoint."""
 
     class Meta:
@@ -396,11 +397,11 @@ def destroy(self, request, *args, **kwargs):
         return super().destroy(
             request,
             *args,
-            **dict(
-                kwargs,
-                delete_sub_locations=delete_sub_locations,
-                delete_stock_items=delete_stock_items,
-            ),
+            **{
+                **kwargs,
+                'delete_sub_locations': delete_sub_locations,
+                'delete_stock_items': delete_stock_items,
+            },
         )
 
 
@@ -476,7 +477,7 @@ def get_queryset(self):
         return queryset
 
 
-class StockFilter(rest_filters.FilterSet):
+class StockFilter(FilterSet):
     """FilterSet for StockItem LIST API."""
 
     class Meta:
@@ -1272,7 +1273,7 @@ class StockItemTestResultDetail(StockItemTestResultMixin, RetrieveUpdateDestroyA
     """Detail endpoint for StockItemTestResult."""
 
 
-class StockItemTestResultFilter(rest_filters.FilterSet):
+class StockItemTestResultFilter(FilterSet):
     """API filter for the StockItemTestResult list."""
 
     class Meta:
diff --git a/src/backend/InvenTree/stock/generators.py b/src/backend/InvenTree/stock/generators.py
index 7b11dc7db8c6..9c0a7aef6eb2 100644
--- a/src/backend/InvenTree/stock/generators.py
+++ b/src/backend/InvenTree/stock/generators.py
@@ -1,6 +1,7 @@
 """Generator functions for the stock app."""
 
 from inspect import signature
+from typing import Optional
 
 from django.core.exceptions import ValidationError
 
@@ -74,7 +75,7 @@ def generate_batch_code(**kwargs):
     return Template(batch_template).render(context)
 
 
-def generate_serial_number(part=None, quantity=1, **kwargs) -> str:
+def generate_serial_number(part=None, quantity=1, **kwargs) -> Optional[str]:
     """Generate a default 'serial number' for a new StockItem."""
     quantity = quantity or 1
 
diff --git a/src/backend/InvenTree/stock/migrations/0061_auto_20210511_0911.py b/src/backend/InvenTree/stock/migrations/0061_auto_20210511_0911.py
index ba44e9c1bd0b..e5d2b823999a 100644
--- a/src/backend/InvenTree/stock/migrations/0061_auto_20210511_0911.py
+++ b/src/backend/InvenTree/stock/migrations/0061_auto_20210511_0911.py
@@ -51,10 +51,10 @@ def update_history(apps, schema_editor):
 
             q = entry.quantity
 
-            if idx == 0 or not q == quantity:
+            if idx == 0 or q != quantity:
 
                 try:
-                    deltas['quantity']: float(q)
+                    deltas['quantity']= float(q)
                     updated = True
                 except Exception:
                     print(f"WARNING: Error converting quantity '{q}'")
diff --git a/src/backend/InvenTree/stock/models.py b/src/backend/InvenTree/stock/models.py
index 168a684eaacf..b08a4f6e1880 100644
--- a/src/backend/InvenTree/stock/models.py
+++ b/src/backend/InvenTree/stock/models.py
@@ -593,7 +593,7 @@ def _create_serial_numbers(cls, serials: list, **kwargs) -> QuerySet:
         return StockItem.objects.filter(part=part, serial__in=serials)
 
     @staticmethod
-    def convert_serial_to_int(serial: str) -> int:
+    def convert_serial_to_int(serial: str) -> Optional[int]:
         """Convert the provided serial number to an integer value.
 
         This function hooks into the plugin system to allow for custom serial number conversion.
@@ -1644,7 +1644,7 @@ def add_tracking_entry(
         self,
         entry_type: int,
         user: User,
-        deltas: dict | None = None,
+        deltas: Optional[dict] = None,
         notes: str = '',
         commit: bool = True,
         **kwargs,
diff --git a/src/backend/InvenTree/stock/serializers.py b/src/backend/InvenTree/stock/serializers.py
index 89eaf4bf4a3f..743692b72daf 100644
--- a/src/backend/InvenTree/stock/serializers.py
+++ b/src/backend/InvenTree/stock/serializers.py
@@ -20,6 +20,7 @@
 import company.models
 import company.serializers as company_serializers
 import InvenTree.helpers
+import InvenTree.ready
 import InvenTree.serializers
 import order.models
 import part.filters as part_filters
diff --git a/src/backend/InvenTree/users/models.py b/src/backend/InvenTree/users/models.py
index cc39ba9ec35b..019891b8700f 100644
--- a/src/backend/InvenTree/users/models.py
+++ b/src/backend/InvenTree/users/models.py
@@ -47,7 +47,9 @@ def user_model_str(self):
 
 
 if settings.LDAP_AUTH:
-    from django_auth_ldap.backend import populate_user
+    from django_auth_ldap.backend import (  # type: ignore[unresolved-import]
+        populate_user,
+    )
 
     @receiver(populate_user)
     def create_email_address(user, **kwargs):
diff --git a/src/backend/InvenTree/users/serializers.py b/src/backend/InvenTree/users/serializers.py
index 5950fb286dd6..522d4ac649be 100644
--- a/src/backend/InvenTree/users/serializers.py
+++ b/src/backend/InvenTree/users/serializers.py
@@ -295,7 +295,7 @@ def get_permissions(self, group: Group) -> dict:
 class ExtendedUserSerializer(UserSerializer):
     """Serializer for a User with a bit more info."""
 
-    from users.serializers import GroupSerializer
+    # from users.serializers import GroupSerializer
 
     class Meta(UserSerializer.Meta):
         """Metaclass defines serializer fields."""
diff --git a/src/backend/InvenTree/web/templatetags/__init__.py b/src/backend/InvenTree/web/templatetags/__init__.py
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/src/backend/InvenTree/web/templatetags/spa_helper.py b/src/backend/InvenTree/web/templatetags/spa_helper.py
index 743d1ef17bd1..0355ca906046 100644
--- a/src/backend/InvenTree/web/templatetags/spa_helper.py
+++ b/src/backend/InvenTree/web/templatetags/spa_helper.py
@@ -1,6 +1,7 @@
 """Template tag to render SPA imports."""
 
 import json
+import json.decoder
 from pathlib import Path
 from typing import Union
 
diff --git a/src/backend/requirements-dev.in b/src/backend/requirements-dev.in
index 42ddbb679c03..d9782f1a19d8 100644
--- a/src/backend/requirements-dev.in
+++ b/src/backend/requirements-dev.in
@@ -9,3 +9,6 @@ pip-tools                               # Compile pip requirements
 pre-commit                              # Git pre-commit
 setuptools                              # Standard dependency
 pdfminer.six                            # PDF validation
+ty                                      # type checking
+django-types                            # typing
+django-stubs                            # typing
diff --git a/src/backend/requirements-dev.txt b/src/backend/requirements-dev.txt
index b63c8d890695..e6439abd1d81 100644
--- a/src/backend/requirements-dev.txt
+++ b/src/backend/requirements-dev.txt
@@ -6,6 +6,7 @@ asgiref==3.8.1 \
     # via
     #   -c src/backend/requirements.txt
     #   django
+    #   django-stubs
 build==1.2.2.post1 \
     --hash=sha256:1d61c0887fa860c01971625baae8bdd338e517b836a2f70dd1f7aa3a6b2fc5b5 \
     --hash=sha256:b36993e92ca9375a219c99e606a122ff365a760a2d4bba0caa09bd5278b608b7
@@ -301,16 +302,30 @@ django==4.2.21 \
     # via
     #   -c src/backend/requirements.txt
     #   django-slowtests
+    #   django-stubs
+    #   django-stubs-ext
 django-querycount==0.8.3 \
     --hash=sha256:0782484e8a1bd29498fa0195a67106e47cdcc98fafe80cebb1991964077cb694
     # via -r src/backend/requirements-dev.in
 django-slowtests==1.1.1 \
     --hash=sha256:3c6936d420c9df444ac03625b41d97de043c662bbde61fbcd33e4cd407d0c247
     # via -r src/backend/requirements-dev.in
+django-stubs==5.1.3 \
+    --hash=sha256:716758ced158b439213062e52de6df3cff7c586f9f9ad7ab59210efbea5dfe78 \
+    --hash=sha256:8c230bc5bebee6da282ba8a27ad1503c84a0c4cd2f46e63d149e76d2a63e639a
+    # via -r src/backend/requirements-dev.in
+django-stubs-ext==5.1.3 \
+    --hash=sha256:3e60f82337f0d40a362f349bf15539144b96e4ceb4dbd0239be1cd71f6a74ad0 \
+    --hash=sha256:64561fbc53e963cc1eed2c8eb27e18b8e48dcb90771205180fe29fc8a59e55fd
+    # via django-stubs
 django-test-migrations==1.4.0 \
     --hash=sha256:294dff98f6d43d020d4046b971bac5339e7c71458a35e9ad6450c388fe16ed6b \
     --hash=sha256:f0c9c92864ed27d0c9a582e92056637e91227f54bd868a50cb9a1726668c563e
     # via -r src/backend/requirements-dev.in
+django-types==0.20.0 \
+    --hash=sha256:4e55d2c56155e3d69d75def9eb1d95a891303f2ac19fccf6fe8056da4293fae7 \
+    --hash=sha256:a0b5c2c9a1e591684bb21a93b64e50ca6cb2d3eab48f49faff1eac706bd3a9c7
+    # via -r src/backend/requirements-dev.in
 filelock==3.18.0 \
     --hash=sha256:adbc88eabb99d2fec8c9c1b229b171f18afa655400173ddc653d5d01501fb9f2 \
     --hash=sha256:c401f4f8377c4464e6db25fff06205fd89bdd83b65eb0488ed1b160f780e21de
@@ -480,13 +495,44 @@ tomli==2.2.1 \
     #   -c src/backend/requirements.txt
     #   build
     #   coverage
+    #   django-stubs
     #   pip-tools
+ty==0.0.1a3 \
+    --hash=sha256:015657bdb165ad01f5baf822ef430c8dec98c5a70f8d86e32cf20ff679bdd57a \
+    --hash=sha256:1b6c38f7252b38d6c3b5517f33b8a5736bdf1313d96d72d2bf2cf7ed96d3e3ee \
+    --hash=sha256:225dcfb52cd757aab1585caa94602e5f87edbab6bd260bbea5c8a821b389baa1 \
+    --hash=sha256:23e9b730ba9c8772801ea16fe5da6007cd7f5cae504b9eb746782600b910c389 \
+    --hash=sha256:28a09ae6c97c38f540af87df5a37e71b91e153dceb7128ff40bfd6742c9a01c5 \
+    --hash=sha256:56e73d152888576932c67c61b295a5428636e3ef15e8a19a83977822b3a8a762 \
+    --hash=sha256:5f7f63794a660cf7d87562bedf124152a9a284b637d80488c13a1cb5ed6aaf85 \
+    --hash=sha256:7f16a4fae298f6886a5dad8e81919bb848b0bb0839f39715a0e0723665092efe \
+    --hash=sha256:8abf6f1c391fe4f506bf36f9e66b3f95844a4c74c01c037a80e71f440073c1e5 \
+    --hash=sha256:90c068448d5a66b8aa0a533380fe8f10d6d6522bc2a20b41ba713029c775f9da \
+    --hash=sha256:aa754e4ff7685910769812d92c1e31b664142c7067b79487e58889aca67fc3ae \
+    --hash=sha256:aef675b51212ee2f5c731fd4b26191f13ef7d51509aafd959685d5716781c875 \
+    --hash=sha256:bb04a11d2b772ddd680f09fffd60c3ee827e5b020a20dd8ce07f2c64ed0d554a \
+    --hash=sha256:c04c852d8382712a8235b05984b22176f9397d58e596d69abf4073729b3404c6 \
+    --hash=sha256:cb0c3d664840d1fefecc63b1cf5a62a2039b039ddca9a868eac51ce3cc1b3ab5 \
+    --hash=sha256:dc7b7617b4ae3471546543e3b5922bfffcfb138c34b19f41d0c102bf6c3f064f \
+    --hash=sha256:f04dd8d6a1db1e8cf40270619a555ea306f7b6bfc265e0919a7b89ee1a467232 \
+    --hash=sha256:f45db3b40b265fd4e4f67d26e038dcdd1a10a9246e09c1b0f310150fc01e101a
+    # via -r src/backend/requirements-dev.in
+types-psycopg2==2.9.21.20250318 \
+    --hash=sha256:7296d111ad950bbd2fc979a1ab0572acae69047f922280e77db657c00d2c79c0 \
+    --hash=sha256:eb6eac5bfb16adfd5f16b818918b9e26a40ede147e0f2bbffdf53a6ef7025a87
+    # via django-types
+types-pyyaml==6.0.12.20250402 \
+    --hash=sha256:652348fa9e7a203d4b0d21066dfb00760d3cbd5a15ebb7cf8d33c88a49546681 \
+    --hash=sha256:d7c13c3e6d335b6af4b0122a01ff1d270aba84ab96d1a1a1063ecba3e13ec075
+    # via django-stubs
 typing-extensions==4.13.2 \
     --hash=sha256:a439e7c04b49fec3e5d3e2beaa21755cadbbdc391694e28ccdd36ca4a1408f8c \
     --hash=sha256:e6c81219bd689f51865d9e372991c540bda33a0379d5573cddb9a3a23f7caaef
     # via
     #   -c src/backend/requirements.txt
     #   asgiref
+    #   django-stubs
+    #   django-stubs-ext
     #   django-test-migrations
 virtualenv==20.31.2 \
     --hash=sha256:36efd0d9650ee985f0cad72065001e66d49a6f24eb44d98980f630686243cf11 \
diff --git a/tasks.py b/tasks.py
index 5e7133c54c50..f7ade23e63fe 100644
--- a/tasks.py
+++ b/tasks.py
@@ -448,7 +448,9 @@ def check_file_existence(filename: Path, overwrite: bool = False):
 @state_logger('TASK01')
 def plugins(c, uv=False):
     """Installs all plugins as specified in 'plugins.txt'."""
-    from src.backend.InvenTree.InvenTree.config import get_plugin_file
+    from src.backend.InvenTree.InvenTree.config import (  # type: ignore[import]
+        get_plugin_file,
+    )
 
     plugin_file = get_plugin_file()
 
@@ -552,7 +554,9 @@ def rebuild_models(c):
 @task
 def rebuild_thumbnails(c):
     """Rebuild missing image thumbnails."""
-    from src.backend.InvenTree.InvenTree.config import get_media_dir
+    from src.backend.InvenTree.InvenTree.config import (  # type: ignore[import]
+        get_media_dir,
+    )
 
     info(f'Rebuilding image thumbnails in {get_media_dir()}')
     manage(c, 'rebuild_thumbnails', pty=True)
@@ -1133,7 +1137,7 @@ def test_translations(c):
     info('Fill in dummy translations...')
 
     file_path = pathlib.Path(settings.LOCALE_PATHS[0], 'xx', 'LC_MESSAGES', 'django.po')
-    new_file_path = str(file_path) + '_new'
+    new_file_path = Path(str(file_path) + '_new')
 
     # compile regex
     reg = re.compile(
@@ -1269,7 +1273,9 @@ def setup_test(
     path='inventree-demo-dataset',
 ):
     """Setup a testing environment."""
-    from src.backend.InvenTree.InvenTree.config import get_media_dir
+    from src.backend.InvenTree.InvenTree.config import (  # type: ignore[import]
+        get_media_dir,
+    )
 
     if not ignore_update:
         update(c)
@@ -1416,8 +1422,8 @@ def export_definitions(c, basedir: str = ''):
 @task(default=True)
 def version(c):
     """Show the current version of InvenTree."""
-    import src.backend.InvenTree.InvenTree.version as InvenTreeVersion
-    from src.backend.InvenTree.InvenTree.config import (
+    import src.backend.InvenTree.InvenTree.version as InvenTreeVersion  # type: ignore[import]
+    from src.backend.InvenTree.InvenTree.config import (  # type: ignore[import]
         get_backup_dir,
         get_config_file,
         get_media_dir,