diff --git a/flake8_trio.py b/flake8_trio.py
index c55f803b..4a43d0a4 100644
--- a/flake8_trio.py
+++ b/flake8_trio.py
@@ -9,24 +9,14 @@
 Pairs well with flake8-async and flake8-bugbear.
 """
 
+from __future__ import annotations
+
 import argparse
 import ast
 import tokenize
 from argparse import Namespace
 from fnmatch import fnmatch
-from typing import (
-    Any,
-    Dict,
-    Iterable,
-    List,
-    NamedTuple,
-    Optional,
-    Sequence,
-    Set,
-    Tuple,
-    Union,
-    cast,
-)
+from typing import Any, Iterable, NamedTuple, Sequence, Union, cast
 
 from flake8.options.manager import OptionManager
 
@@ -95,7 +85,7 @@ def __eq__(self, other: Any) -> bool:
 
 def get_matching_call(
     node: ast.AST, *names: str, base: str = "trio"
-) -> Optional[Tuple[ast.Call, str]]:
+) -> tuple[ast.Call, str] | None:
     if (
         isinstance(node, ast.Call)
         and isinstance(node.func, ast.Attribute)
@@ -150,7 +140,7 @@ def __repr__(self) -> str:
 class Flake8TrioVisitor(ast.NodeVisitor):
     def __init__(self, options: Namespace):
         super().__init__()
-        self._problems: List[Error] = []
+        self._problems: list[Error] = []
         self.suppress_errors = False
         self.options = options
 
@@ -160,9 +150,7 @@ def run(cls, tree: ast.AST, options: Namespace) -> Iterable[Error]:
         visitor.visit(tree)
         yield from visitor._problems
 
-    def visit_nodes(
-        self, *nodes: Union[ast.AST, Iterable[ast.AST]], generic: bool = False
-    ):
+    def visit_nodes(self, *nodes: ast.AST | Iterable[ast.AST], generic: bool = False):
         if generic:
             visit = self.generic_visit
         else:
@@ -178,10 +166,10 @@ def error(self, error: str, node: HasLineCol, *args: object):
         if not self.suppress_errors:
             self._problems.append(Error(error, node.lineno, node.col_offset, *args))
 
-    def get_state(self, *attrs: str, copy: bool = False) -> Dict[str, Any]:
+    def get_state(self, *attrs: str, copy: bool = False) -> dict[str, Any]:
         if not attrs:
             attrs = tuple(self.__dict__.keys())
-        res: Dict[str, Any] = {}
+        res: dict[str, Any] = {}
         for attr in attrs:
             if attr == "_problems":
                 continue
@@ -191,7 +179,7 @@ def get_state(self, *attrs: str, copy: bool = False) -> Dict[str, Any]:
             res[attr] = value
         return res
 
-    def set_state(self, attrs: Dict[str, Any], copy: bool = False):
+    def set_state(self, attrs: dict[str, Any], copy: bool = False):
         for attr, value in attrs.items():
             if copy and hasattr(value, "copy"):
                 value = value.copy()
@@ -203,7 +191,7 @@ def walk(self, *body: ast.AST) -> Iterable[ast.AST]:
 
 
 # ignores module and only checks the unqualified name of the decorator
-def has_decorator(decorator_list: List[ast.expr], *names: str):
+def has_decorator(decorator_list: list[ast.expr], *names: str):
     for dec in decorator_list:
         if (isinstance(dec, ast.Name) and dec.id in names) or (
             isinstance(dec, ast.Attribute) and dec.attr in names
@@ -214,8 +202,8 @@ def has_decorator(decorator_list: List[ast.expr], *names: str):
 
 # matches the fully qualified name against fnmatch pattern
 # used to match decorators and methods to user-supplied patterns
-def fnmatch_qualified_name(name_list: List[ast.expr], *patterns: str):
-    def construct_name(expr: ast.expr) -> Optional[str]:
+def fnmatch_qualified_name(name_list: list[ast.expr], *patterns: str):
+    def construct_name(expr: ast.expr) -> str | None:
         if isinstance(expr, ast.Call):
             expr = expr.func
         if isinstance(expr, ast.Name):
@@ -257,13 +245,13 @@ def __init__(self, *args: Any, **kwargs: Any):
         self._safe_decorator = False
 
         # 111
-        self._context_managers: List[VisitorMiscChecks.TrioContextManager] = []
-        self._nursery_call: Optional[VisitorMiscChecks.NurseryCall] = None
+        self._context_managers: list[VisitorMiscChecks.TrioContextManager] = []
+        self._nursery_call: VisitorMiscChecks.NurseryCall | None = None
 
         self.defaults = self.get_state(copy=True)
 
     # ---- 100, 101, 111, 112 ----
-    def visit_With(self, node: Union[ast.With, ast.AsyncWith]):
+    def visit_With(self, node: ast.With | ast.AsyncWith):
         self.check_for_trio100(node)
         self.check_for_trio112(node)
 
@@ -305,7 +293,7 @@ def visit_With(self, node: Union[ast.With, ast.AsyncWith]):
     visit_AsyncWith = visit_With
 
     # ---- 100 ----
-    def check_for_trio100(self, node: Union[ast.With, ast.AsyncWith]):
+    def check_for_trio100(self, node: ast.With | ast.AsyncWith):
         # Context manager with no `await trio.X` call within
         for item in (i.context_expr for i in node.items):
             call = get_matching_call(item, *cancel_scope_names)
@@ -316,7 +304,7 @@ def check_for_trio100(self, node: Union[ast.With, ast.AsyncWith]):
                 self.error("TRIO100", item, f"trio.{call[1]}")
 
     # ---- 101 ----
-    def visit_FunctionDef(self, node: Union[ast.FunctionDef, ast.AsyncFunctionDef]):
+    def visit_FunctionDef(self, node: ast.FunctionDef | ast.AsyncFunctionDef):
         outer = self.get_state()
         self.set_state(self.defaults, copy=True)
 
@@ -433,7 +421,7 @@ def visit_Name(self, node: ast.Name):
     # if with has a withitem `trio.open_nursery() as <X>`,
     # and the body is only a single expression <X>.start[_soon](),
     # and does not pass <X> as a parameter to the expression
-    def check_for_trio112(self, node: Union[ast.With, ast.AsyncWith]):
+    def check_for_trio112(self, node: ast.With | ast.AsyncWith):
         # body is single expression
         if len(node.body) != 1 or not isinstance(node.body[0], ast.Expr):
             return
@@ -462,8 +450,8 @@ def check_for_trio112(self, node: Union[ast.With, ast.AsyncWith]):
 
 
 # used in 102, 103 and 104
-def critical_except(node: ast.ExceptHandler) -> Optional[Statement]:
-    def has_exception(node: Optional[ast.expr]) -> str:
+def critical_except(node: ast.ExceptHandler) -> Statement | None:
+    def has_exception(node: ast.expr | None) -> str:
         if isinstance(node, ast.Name) and node.id == "BaseException":
             return "BaseException"
         if (
@@ -496,7 +484,7 @@ class TrioScope:
         def __init__(self, node: ast.Call, funcname: str):
             self.node = node
             self.funcname = funcname
-            self.variable_name: Optional[str] = None
+            self.variable_name: str | None = None
             self.shielded: bool = False
             self.has_timeout: bool = True
 
@@ -514,14 +502,14 @@ def __init__(self, node: ast.Call, funcname: str):
 
     def __init__(self, *args: Any, **kwargs: Any):
         super().__init__(*args, **kwargs)
-        self._critical_scope: Optional[Statement] = None
-        self._trio_context_managers: List[Visitor102.TrioScope] = []
+        self._critical_scope: Statement | None = None
+        self._trio_context_managers: list[Visitor102.TrioScope] = []
 
     # if we're inside a finally, and we're not inside a scope that doesn't have
     # both a timeout and shield
     def visit_Await(
         self,
-        node: Union[ast.Await, ast.AsyncFor, ast.AsyncWith],
+        node: ast.Await | ast.AsyncFor | ast.AsyncWith,
         visit_children: bool = True,
     ):
         if self._critical_scope is not None and not any(
@@ -533,7 +521,7 @@ def visit_Await(
 
     visit_AsyncFor = visit_Await
 
-    def visit_With(self, node: Union[ast.With, ast.AsyncWith]):
+    def visit_With(self, node: ast.With | ast.AsyncWith):
         has_context_manager = False
 
         # Check for a `with trio.<scope_creater>`
@@ -564,7 +552,7 @@ def visit_AsyncWith(self, node: ast.AsyncWith):
 
     def critical_visit(
         self,
-        node: Union[ast.ExceptHandler, Iterable[ast.AST]],
+        node: ast.ExceptHandler | Iterable[ast.AST],
         block: Statement,
         generic: bool = False,
     ):
@@ -612,7 +600,7 @@ def visit_Assign(self, node: ast.Assign):
 class Visitor103_104(Flake8TrioVisitor):
     def __init__(self, *args: Any, **kwargs: Any):
         super().__init__(*args, **kwargs)
-        self.except_name: Optional[str] = ""
+        self.except_name: str | None = ""
         self.unraised: bool = False
         self.unraised_break: bool = False
         self.unraised_continue: bool = False
@@ -659,7 +647,7 @@ def visit_Raise(self, node: ast.Raise):
 
         self.generic_visit(node)
 
-    def visit_Return(self, node: Union[ast.Return, ast.Yield]):
+    def visit_Return(self, node: ast.Return | ast.Yield):
         if self.unraised:
             # Error: must re-raise
             self.error("TRIO104", node)
@@ -709,7 +697,7 @@ def visit_If(self, node: ast.If):
     #   else always raises, and
     #   always raise before break
     # or body always raises (before break) and is guaranteed to run at least once
-    def visit_For(self, node: Union[ast.For, ast.While]):
+    def visit_For(self, node: ast.For | ast.While):
         if not self.unraised:
             self.generic_visit(node)
             return
@@ -829,7 +817,7 @@ class Visitor105(Flake8TrioVisitor):
     def __init__(self, *args: Any, **kwargs: Any):
         super().__init__(*args, **kwargs)
         # keep a node stack so we can check whether calls are awaited
-        self.node_stack: List[ast.AST] = []
+        self.node_stack: list[ast.AST] = []
 
     def visit(self, node: ast.AST):
         self.node_stack.append(node)
@@ -854,7 +842,7 @@ def visit_Call(self, node: ast.Call):
         self.generic_visit(node)
 
 
-def empty_body(body: List[ast.stmt]) -> bool:
+def empty_body(body: list[ast.stmt]) -> bool:
     # Does the function body consist solely of `pass`, `...`, and (doc)string literals?
     return all(
         isinstance(stmt, ast.Pass)
@@ -874,9 +862,9 @@ def __init__(self, *args: Any, **kwargs: Any):
         self.safe_decorator = False
         self.async_function = False
 
-        self.uncheckpointed_statements: Set[Statement] = set()
-        self.uncheckpointed_before_continue: Set[Statement] = set()
-        self.uncheckpointed_before_break: Set[Statement] = set()
+        self.uncheckpointed_statements: set[Statement] = set()
+        self.uncheckpointed_before_continue: set[Statement] = set()
+        self.uncheckpointed_before_break: set[Statement] = set()
 
         self.default = self.get_state()
 
@@ -913,7 +901,7 @@ def visit_AsyncFunctionDef(self, node: ast.AsyncFunctionDef):
         self.set_state(outer)
 
     # error if function exits or returns with uncheckpointed statements
-    def check_function_exit(self, node: Union[ast.Return, ast.AsyncFunctionDef]):
+    def check_function_exit(self, node: ast.Return | ast.AsyncFunctionDef):
         for statement in self.uncheckpointed_statements:
             self.error(
                 "TRIO108" if self.has_yield else "TRIO107",
@@ -937,7 +925,7 @@ def visit_FunctionDef(self, node: ast.FunctionDef):
         self.set_state(outer)
 
     # checkpoint functions
-    def visit_Await(self, node: Union[ast.Await, ast.Raise]):
+    def visit_Await(self, node: ast.Await | ast.Raise):
         # the expression being awaited is not checkpointed
         # so only set checkpoint after the await node
         self.generic_visit(node)
@@ -994,7 +982,7 @@ def visit_Try(self, node: ast.Try):
         try_checkpoint = self.uncheckpointed_statements
 
         # check that all except handlers checkpoint (await or most likely raise)
-        except_uncheckpointed_statements: Set[Statement] = set()
+        except_uncheckpointed_statements: set[Statement] = set()
 
         for handler in node.handlers:
             # enter with worst case of try
@@ -1032,7 +1020,7 @@ def visit_Try(self, node: ast.Try):
             self.uncheckpointed_statements.difference_update(added)
 
     # valid checkpoint if both body and orelse checkpoint
-    def visit_If(self, node: Union[ast.If, ast.IfExp]):
+    def visit_If(self, node: ast.If | ast.IfExp):
         # visit condition
         self.visit_nodes(node.test)
         outer = self.uncheckpointed_statements.copy()
@@ -1055,7 +1043,7 @@ def visit_If(self, node: Union[ast.If, ast.IfExp]):
     # after completing all of loop body, and after any continues.
     # yield in else have same requirement
     # state after the loop same as above, and in addition the state at any break
-    def visit_loop(self, node: Union[ast.While, ast.For, ast.AsyncFor]):
+    def visit_loop(self, node: ast.While | ast.For | ast.AsyncFor):
         # visit condition
         infinite_loop = False
         if isinstance(node, ast.While):
@@ -1307,8 +1295,8 @@ def __call__(
         self,
         parser: argparse.ArgumentParser,
         namespace: argparse.Namespace,
-        values: Optional[Sequence[Any]],
-        option_string: Optional[str] = None,
+        values: Sequence[Any] | None,
+        option_string: str | None = None,
     ):
         assert values is not None
         assert option_string is not None
@@ -1327,7 +1315,7 @@ def __init__(self, tree: ast.AST):
         self._tree = tree
 
     @classmethod
-    def from_filename(cls, filename: str) -> "Plugin":
+    def from_filename(cls, filename: str) -> Plugin:
         with tokenize.open(filename) as f:
             source = f.read()
         return cls(ast.parse(source))
diff --git a/tests/conftest.py b/tests/conftest.py
index af3a52de..0bc2c0da 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -1,4 +1,4 @@
-from typing import List
+from __future__ import annotations
 
 import pytest
 
@@ -15,7 +15,7 @@ def pytest_configure(config: pytest.Config):
     )
 
 
-def pytest_collection_modifyitems(config: pytest.Config, items: List[pytest.Item]):
+def pytest_collection_modifyitems(config: pytest.Config, items: list[pytest.Item]):
     if config.getoption("--runfuzz"):
         # --runfuzz given in cli: do not skip fuzz tests
         return
diff --git a/tests/test_changelog_and_version.py b/tests/test_changelog_and_version.py
index e925a287..2c8c941d 100644
--- a/tests/test_changelog_and_version.py
+++ b/tests/test_changelog_and_version.py
@@ -1,9 +1,11 @@
 """Tests for flake8-trio package metadata."""
+from __future__ import annotations
+
 import os
 import re
 import unittest
 from pathlib import Path
-from typing import Dict, Iterable, NamedTuple, Set
+from typing import Iterable, NamedTuple
 
 from test_flake8_trio import trio_test_files_regex
 
@@ -51,7 +53,7 @@ def test_version_increments_are_correct():
 
 class test_messages_documented(unittest.TestCase):
     def runTest(self):
-        documented_errors: Dict[str, Set[str]] = {}
+        documented_errors: dict[str, set[str]] = {}
         for filename in (
             "CHANGELOG.md",
             "README.md",
@@ -71,8 +73,8 @@ def runTest(self):
             if re.match(trio_test_files_regex, f)
         }
 
-        unique_errors: Dict[str, Set[str]] = {}
-        missing_errors: Dict[str, Set[str]] = {}
+        unique_errors: dict[str, set[str]] = {}
+        missing_errors: dict[str, set[str]] = {}
         for key, codes in documented_errors.items():
             unique_errors[key] = codes.copy()
             missing_errors[key] = set()
diff --git a/tests/test_decorator.py b/tests/test_decorator.py
index 90937b8d..9399989d 100644
--- a/tests/test_decorator.py
+++ b/tests/test_decorator.py
@@ -1,7 +1,8 @@
+from __future__ import annotations
+
 import ast
 import sys
 from argparse import Namespace
-from typing import Tuple
 
 import pytest
 from flake8.main.application import Application
@@ -18,7 +19,7 @@ def dec_list(*decorators: str) -> ast.Module:
     return tree
 
 
-def wrap(decorators: Tuple[str, ...], decs2: str) -> bool:
+def wrap(decorators: tuple[str, ...], decs2: str) -> bool:
     tree = dec_list(*decorators)
     assert isinstance(tree.body[0], ast.AsyncFunctionDef)
     return fnmatch_qualified_name(tree.body[0].decorator_list, decs2)
diff --git a/tests/test_flake8_trio.py b/tests/test_flake8_trio.py
index 29489272..f529381a 100644
--- a/tests/test_flake8_trio.py
+++ b/tests/test_flake8_trio.py
@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import ast
 import copy
 import itertools
@@ -8,7 +10,7 @@
 import tokenize
 import unittest
 from pathlib import Path
-from typing import DefaultDict, Iterable, List, Sequence, Tuple, Type
+from typing import DefaultDict, Iterable, Sequence
 
 import pytest
 from flake8 import __version_info__ as flake8_version_info
@@ -22,7 +24,7 @@
 
 trio_test_files_regex = re.compile(r"trio\d\d\d(_py.*)?.py")
 
-test_files: List[Tuple[str, str]] = sorted(
+test_files: list[tuple[str, str]] = sorted(
     (os.path.splitext(f)[0].upper(), f)
     for f in os.listdir("tests")
     if re.match(trio_test_files_regex, f)
@@ -62,7 +64,7 @@ def test_eval(test: str, path: str):
     assert test in Error_codes.keys(), "error code not defined in flake8_trio.py"
 
     include = [test]
-    expected: List[Error] = []
+    expected: list[Error] = []
     with open(os.path.join("tests", path), encoding="utf-8") as file:
         lines = file.readlines()
 
@@ -134,7 +136,7 @@ def visit_Await(self, node: ast.Await):
         newnode = self.generic_visit(node.value)
         return newnode
 
-    def replace_async(self, node: ast.AST, target: Type[ast.AST]) -> ast.AST:
+    def replace_async(self, node: ast.AST, target: type[ast.AST]) -> ast.AST:
         node = self.generic_visit(node)
         newnode = target()
         newnode.__dict__ = node.__dict__
@@ -188,8 +190,8 @@ def assert_expected_errors(plugin: Plugin, include: Iterable[str], *expected: Er
 
 
 def print_first_diff(errors: Sequence[Error], expected: Sequence[Error]):
-    first_error_line: List[Error] = []
-    first_expected_line: List[Error] = []
+    first_error_line: list[Error] = []
+    first_expected_line: list[Error] = []
     for err, exp in zip(errors, expected):
         if err == exp:
             continue
diff --git a/typings/flake8/__init__.pyi b/typings/flake8/__init__.pyi
index bf8f2de6..2745afa7 100644
--- a/typings/flake8/__init__.pyi
+++ b/typings/flake8/__init__.pyi
@@ -5,8 +5,6 @@ This type stub file was generated by pyright.
 from __future__ import annotations
 
 import logging
-import sys
-from typing import Dict, Tuple
 
 """Top-level module for Flake8.
 
@@ -21,8 +19,8 @@ This module
 """
 LOG: logging.Logger = ...
 __version__: str = ...
-__version_info__: Tuple[int, ...] = ...
-_VERBOSITY_TO_LOG_LEVEL: Dict[int, int] = ...
+__version_info__: tuple[int, ...] = ...
+_VERBOSITY_TO_LOG_LEVEL: dict[int, int] = ...
 LOG_FORMAT: str = ...
 
 def configure_logging(
diff --git a/typings/flake8/options/manager.pyi b/typings/flake8/options/manager.pyi
index 89e2d324..540a60f3 100644
--- a/typings/flake8/options/manager.pyi
+++ b/typings/flake8/options/manager.pyi
@@ -3,18 +3,14 @@ This type stub file was generated by pyright.
 Generated for flake8 5, so OptionManager signature is incorrect for flake8 6
 """
 
+from __future__ import annotations
+
 import argparse
 from typing import (
     Any,
     Callable,
-    Dict,
-    List,
     Mapping,
-    Optional,
     Sequence,
-    Tuple,
-    Type,
-    Union,
 )
 
 from flake8.plugins.finder import Plugins
@@ -22,7 +18,7 @@ from flake8.plugins.finder import Plugins
 """Option handling and Option management logic."""
 LOG = ...
 _ARG = ...
-_optparse_callable_map: Dict[str, Union[Type[Any], _ARG]] = ...
+_optparse_callable_map: dict[str, type[Any] | _ARG] = ...
 
 class _CallbackAction(argparse.Action):
     """Shim for optparse-style callback actions."""
@@ -32,15 +28,15 @@ class _CallbackAction(argparse.Action):
         *args: Any,
         callback: Callable[..., Any],
         callback_args: Sequence[Any] = ...,
-        callback_kwargs: Optional[Dict[str, Any]] = ...,
+        callback_kwargs: dict[str, Any] | None = ...,
         **kwargs: Any,
     ) -> None: ...
     def __call__(
         self,
         parser: argparse.ArgumentParser,
         namespace: argparse.Namespace,
-        values: Optional[Union[Sequence[str], str]],
-        option_string: Optional[str] = ...,
+        values: Sequence[str] | str | None,
+        option_string: str | None = ...,
     ) -> None: ...
 
 class Option:
@@ -48,21 +44,21 @@ class Option:
 
     def __init__(
         self,
-        short_option_name: Union[str, _ARG] = ...,
-        long_option_name: Union[str, _ARG] = ...,
-        action: Union[str, Type[argparse.Action], _ARG] = ...,
-        default: Union[Any, _ARG] = ...,
-        type: Union[str, Callable[..., Any], _ARG] = ...,
-        dest: Union[str, _ARG] = ...,
-        nargs: Union[int, str, _ARG] = ...,
-        const: Union[Any, _ARG] = ...,
-        choices: Union[Sequence[Any], _ARG] = ...,
-        help: Union[str, _ARG] = ...,
-        metavar: Union[str, _ARG] = ...,
-        callback: Union[Callable[..., Any], _ARG] = ...,
-        callback_args: Union[Sequence[Any], _ARG] = ...,
-        callback_kwargs: Union[Mapping[str, Any], _ARG] = ...,
-        required: Union[bool, _ARG] = ...,
+        short_option_name: str | _ARG = ...,
+        long_option_name: str | _ARG = ...,
+        action: str | type[argparse.Action] | _ARG = ...,
+        default: Any | _ARG = ...,
+        type: str | Callable[..., Any] | _ARG = ...,
+        dest: str | _ARG = ...,
+        nargs: int | str | _ARG = ...,
+        const: Any | _ARG = ...,
+        choices: Sequence[Any] | _ARG = ...,
+        help: str | _ARG = ...,
+        metavar: str | _ARG = ...,
+        callback: Callable[..., Any] | _ARG = ...,
+        callback_args: Sequence[Any] | _ARG = ...,
+        callback_kwargs: Mapping[str, Any] | _ARG = ...,
+        required: bool | _ARG = ...,
         parse_from_config: bool = ...,
         comma_separated_list: bool = ...,
         normalize_paths: bool = ...,
@@ -130,14 +126,14 @@ class Option:
         """
         ...
     @property
-    def filtered_option_kwargs(self) -> Dict[str, Any]:
+    def filtered_option_kwargs(self) -> dict[str, Any]:
         """Return any actually-specified arguments."""
         ...
     def __repr__(self) -> str: ...
     def normalize(self, value: Any, *normalize_args: str) -> Any:
         """Normalize the value based on the option configuration."""
         ...
-    def to_argparse(self) -> Tuple[List[str], Dict[str, Any]]:
+    def to_argparse(self) -> tuple[list[str], dict[str, Any]]:
         """Convert a Flake8 Option to argparse ``add_argument`` arguments."""
         ...
 
@@ -149,7 +145,7 @@ class OptionManager:
         *,
         version: str,
         plugin_versions: str,
-        parents: List[argparse.ArgumentParser],
+        parents: list[argparse.ArgumentParser],
     ) -> None:
         """Initialize an instance of an OptionManager.
 
@@ -197,8 +193,8 @@ class OptionManager:
         ...
     def parse_args(
         self,
-        args: Optional[Sequence[str]] = ...,
-        values: Optional[argparse.Namespace] = ...,
+        args: Sequence[str] | None = ...,
+        values: argparse.Namespace | None = ...,
     ) -> argparse.Namespace:
         """Proxy to calling the OptionParser's parse_args method."""
         ...