diff --git a/CHANGELOG.md b/CHANGELOG.md
index aae03b1..64b2e02 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,9 @@
 # Changelog
+## Pedantic 2.2.3
+- remove support for deprecated `typing.ByteString`
+- fix `WithDecoratedMethods`
+- use start method `spawn` for `multiprocess`
+
 ## Pedantic 2.2.2
 - fix `GenericMixin`
 
diff --git a/pedantic/decorators/fn_deco_in_subprocess.py b/pedantic/decorators/fn_deco_in_subprocess.py
index 8809d49..dfc285e 100644
--- a/pedantic/decorators/fn_deco_in_subprocess.py
+++ b/pedantic/decorators/fn_deco_in_subprocess.py
@@ -4,8 +4,11 @@
 from typing import Callable, TypeVar, Any, Awaitable, Optional, Type, Union
 
 try:
+    import multiprocess as mp
     from multiprocess import Process, Pipe
     from multiprocess.connection import Connection
+
+    mp.set_start_method(method="spawn", force=True)
 except ImportError:
     Process: Optional[Type] = None
     Pipe: Optional[Type] = None
diff --git a/pedantic/mixins/with_decorated_methods.py b/pedantic/mixins/with_decorated_methods.py
index 9c7826c..7a86abf 100644
--- a/pedantic/mixins/with_decorated_methods.py
+++ b/pedantic/mixins/with_decorated_methods.py
@@ -11,13 +11,14 @@ class DecoratorType(StrEnum):
 
     The values of this enum are used as property names and the properties are added to the decorated functions.
     So I would recommend naming them with a leading underscore to keep them private and also write it lowercase.
+
     Example:
         >>> class Decorators(DecoratorType):
         ...     FOO = '_foo'
     """
 
 
-E = TypeVar('E', bound=DecoratorType)
+DecoratorTypeVar = TypeVar('DecoratorTypeVar', bound=DecoratorType)
 T = TypeVar('T')
 C = TypeVar('C', bound=Callable)
 
@@ -45,7 +46,7 @@ def fun(f: C) -> C:
     return decorator
 
 
-class WithDecoratedMethods(ABC, Generic[E], GenericMixin):
+class WithDecoratedMethods(ABC, Generic[DecoratorTypeVar], GenericMixin):
     """
     A mixin that is used to figure out which method is decorated with custom parameterized decorators.
     Example:
@@ -79,12 +80,12 @@ class WithDecoratedMethods(ABC, Generic[E], GenericMixin):
         }
     """
 
-    def get_decorated_functions(self) -> dict[E, dict[C, T]]:
-        decorator_types = self.type_var
+    def get_decorated_functions(self) -> dict[DecoratorTypeVar, dict[C, T]]:
+        decorator_types = self.type_vars[DecoratorTypeVar]
         decorated_functions = {t: dict() for t in decorator_types}  # type: ignore
 
         for attribute_name in dir(self):
-            if attribute_name.startswith('__'):
+            if attribute_name.startswith('__') or attribute_name in ['type_var', 'type_vars']:
                 continue
 
             attribute = getattr(self, attribute_name)
diff --git a/pedantic/tests/test_with_decorated_methods.py b/pedantic/tests/test_with_decorated_methods.py
index b095712..b05325c 100644
--- a/pedantic/tests/test_with_decorated_methods.py
+++ b/pedantic/tests/test_with_decorated_methods.py
@@ -1,8 +1,10 @@
 import unittest
 from functools import wraps
+from typing import TypeVar, Generic
 
 from pedantic import DecoratorType, create_decorator, WithDecoratedMethods
 
+T = TypeVar('T')
 
 class Decorators(DecoratorType):
     FOO = '_foo'
@@ -96,3 +98,12 @@ def m1(self) -> int:
         assert instance.get_decorated_functions() == expected
 
         assert instance.m1() == 4422  # check that transformation was applied
+
+    def test_with_decorated_methods_can_have_generic_child_class(self):
+        class MyClass(Generic[T], WithDecoratedMethods[Decorators]):
+            @foo(42)
+            def m1(self) -> None: ...
+
+        instance = MyClass[int]()
+        actual = instance.get_decorated_functions()
+        assert actual == {Decorators.FOO: {instance.m1: 42}, Decorators.BAR: {}}
\ No newline at end of file
diff --git a/pedantic/type_checking_logic/check_types.py b/pedantic/type_checking_logic/check_types.py
index 32a49b7..293329c 100644
--- a/pedantic/type_checking_logic/check_types.py
+++ b/pedantic/type_checking_logic/check_types.py
@@ -3,7 +3,7 @@
 import types
 import typing
 from io import BytesIO, StringIO, BufferedWriter, TextIOWrapper
-from typing import Any, Dict, Iterable, ItemsView, Callable, Union, Optional, Tuple, Mapping, TypeVar, NewType, \
+from typing import Any, Dict, Iterable, ItemsView, Callable, Optional, Tuple, Mapping, TypeVar, NewType, \
     _ProtocolMeta
 import collections
 
@@ -965,7 +965,6 @@ def _instancecheck_type(value: Any, type_: Any, type_vars: Dict, context: Dict[s
     'typing.Sequence': _instancecheck_iterable,
     'typing.Iterable': _instancecheck_iterable,
     'typing.MutableSequence': _instancecheck_iterable,
-    'typing.ByteString': _instancecheck_iterable,
     'typing.Deque': _instancecheck_iterable,
     'typing.List': _instancecheck_iterable,
     'typing.Set': _instancecheck_iterable,
diff --git a/pyproject.toml b/pyproject.toml
index a59938b..92ecf82 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "pedantic"
-version = "2.2.2"
+version = "2.2.3"
 description = "Some useful Python decorators for cleaner software development."
 readme = "README.md"
 requires-python = ">=3.11"