diff --git a/src/nipanel/_typing.py b/src/nipanel/_typing.py
index 59817c5..877f1ff 100644
--- a/src/nipanel/_typing.py
+++ b/src/nipanel/_typing.py
@@ -1,25 +1,133 @@
-"""Single source for typing backports to avoid depending on typing_extensions at run time."""
+"""Version-specific compatibility shims for the standard `typing` module.
+
+For `typing` symbols that require Python 3.10 or later, this submodule redirects to the standard
+`typing` module (when appropriate), the `typing_extensions` package, or provides a minimial stub
+implementation for run time. This allows us to use new typing features without littering the rest of
+our code with conditionals or making our Python packages depend on `typing_extenions` at run time.
+
+For `typing` symbols that are supported in Python 3.9, you do not need this submodule. Import these
+symbols directly from the standard `typing` module.
+
+This submodule is vendored in multiple packages (nitypes, nipanel, etc.) to avoid compatibility
+breakage when upgrading these packages.
+
+Do not add project-specific types to this submodule.
+
+Many of these symbosl are references to `None` at run time. Clients of this submodule should use
+`from __future__ import annotations` to avoid parsing type hints at run time.
+"""
 
 from __future__ import annotations
 
 import sys
 from typing import TYPE_CHECKING
 
+if sys.version_info >= (3, 10):
+    from typing import (
+        Concatenate,
+        ParamSpec,
+        ParamSpecArgs,
+        ParamSpecKwargs,
+        TypeAlias,
+        TypeGuard,
+    )
+elif TYPE_CHECKING:
+    from typing_extensions import (
+        Concatenate,
+        ParamSpec,
+        ParamSpecArgs,
+        ParamSpecKwargs,
+        TypeAlias,
+        TypeGuard,
+    )
+else:
+    Concatenate = ParamSpecArgs = ParamSpecKwargs = TypeAlias = TypeGuard = None
+
+    def ParamSpec(  # noqa: D103, N802 - Missing docstring, wrong case
+        name, *, bound=None, covariant=False, contravariant=False
+    ):
+        return None
+
+
 if sys.version_info >= (3, 11):
-    from typing import Self
+    from typing import (
+        LiteralString,
+        Never,
+        NotRequired,
+        Required,
+        Self,
+        TypeVarTuple,
+        Unpack,
+        assert_never,
+        assert_type,
+        reveal_type,
+    )
 elif TYPE_CHECKING:
-    from typing_extensions import Self
+    from typing_extensions import (
+        LiteralString,
+        Never,
+        NotRequired,
+        Required,
+        Self,
+        TypeVarTuple,
+        Unpack,
+        assert_never,
+        assert_type,
+        reveal_type,
+    )
 else:
-    Self = None
+    LiteralString = Never = NotRequired = Required = Self = Unpack = None
 
-if sys.version_info >= (3, 10):
-    from typing import ParamSpec
+    def assert_never(arg, /):  # noqa: D103 - Missing docstring in public function
+        pass
+
+    def assert_type(val, typ, /):  # noqa: D103 - Missing docstring in public function
+        pass
+
+    def reveal_type(obj, /):  # noqa: D103 - Missing docstring in public function
+        pass
+
+    def TypeVarTuple(name):  # noqa: D103, N802 - Missing docstring, wrong case
+        return None
+
+
+if sys.version_info >= (3, 12):
+    from typing import TypeAliasType, override
+elif TYPE_CHECKING:
+    from typing_extensions import TypeAliasType, override
+else:
+    TypeAliasType = None
+
+    def override(arg, /):  # noqa: D103 - Missing docstring in public function
+        return arg
+
+
+if sys.version_info >= (3, 13):
+    from typing import ReadOnly, TypeIs
 elif TYPE_CHECKING:
-    from typing_extensions import ParamSpec
+    from typing_extensions import ReadOnly, TypeIs
 else:
-    from typing import TypeVar as ParamSpec
+    ReadOnly = TypeIs = None
 
 __all__ = [
-    "Self",
+    "assert_never",
+    "assert_type",
+    "Concatenate",
+    "LiteralString",
+    "Never",
+    "NotRequired",
+    "override",
     "ParamSpec",
+    "ParamSpecArgs",
+    "ParamSpecKwargs",
+    "ReadOnly",
+    "Required",
+    "reveal_type",
+    "Self",
+    "TypeAlias",
+    "TypeAliasType",
+    "TypeGuard",
+    "TypeIs",
+    "TypeVarTuple",
+    "Unpack",
 ]