diff --git a/.gitignore b/.gitignore
index 11b71aa3a..c3c267ce6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -43,3 +43,6 @@ Pipfile.lock
 
 # pyenv version file
 .python-version
+
+# uv
+uv.lock
diff --git a/cmd2/ansi.py b/cmd2/ansi.py
index d2f6832a8..52bf382a1 100644
--- a/cmd2/ansi.py
+++ b/cmd2/ansi.py
@@ -2,7 +2,8 @@
 """
 Support for ANSI escape sequences which are used for things like applying style to text,
 setting the window title, and asynchronous alerts.
- """
+"""
+
 import functools
 import re
 from enum import (
@@ -62,25 +63,25 @@ def __repr__(self) -> str:
 """
 
 # Regular expression to match ANSI style sequence
-ANSI_STYLE_RE = re.compile(fr'{ESC}\[[^m]*m')
+ANSI_STYLE_RE = re.compile(rf'{ESC}\[[^m]*m')
 
 # Matches standard foreground colors: CSI(30-37|90-97|39)m
-STD_FG_RE = re.compile(fr'{ESC}\[(?:[39][0-7]|39)m')
+STD_FG_RE = re.compile(rf'{ESC}\[(?:[39][0-7]|39)m')
 
 # Matches standard background colors: CSI(40-47|100-107|49)m
-STD_BG_RE = re.compile(fr'{ESC}\[(?:(?:4|10)[0-7]|49)m')
+STD_BG_RE = re.compile(rf'{ESC}\[(?:(?:4|10)[0-7]|49)m')
 
 # Matches eight-bit foreground colors: CSI38;5;(0-255)m
-EIGHT_BIT_FG_RE = re.compile(fr'{ESC}\[38;5;(?:1?[0-9]?[0-9]?|2[0-4][0-9]|25[0-5])m')
+EIGHT_BIT_FG_RE = re.compile(rf'{ESC}\[38;5;(?:1?[0-9]?[0-9]?|2[0-4][0-9]|25[0-5])m')
 
 # Matches eight-bit background colors: CSI48;5;(0-255)m
-EIGHT_BIT_BG_RE = re.compile(fr'{ESC}\[48;5;(?:1?[0-9]?[0-9]?|2[0-4][0-9]|25[0-5])m')
+EIGHT_BIT_BG_RE = re.compile(rf'{ESC}\[48;5;(?:1?[0-9]?[0-9]?|2[0-4][0-9]|25[0-5])m')
 
 # Matches RGB foreground colors: CSI38;2;(0-255);(0-255);(0-255)m
-RGB_FG_RE = re.compile(fr'{ESC}\[38;2(?:;(?:1?[0-9]?[0-9]?|2[0-4][0-9]|25[0-5])){{3}}m')
+RGB_FG_RE = re.compile(rf'{ESC}\[38;2(?:;(?:1?[0-9]?[0-9]?|2[0-4][0-9]|25[0-5])){{3}}m')
 
 # Matches RGB background colors: CSI48;2;(0-255);(0-255);(0-255)m
-RGB_BG_RE = re.compile(fr'{ESC}\[48;2(?:;(?:1?[0-9]?[0-9]?|2[0-4][0-9]|25[0-5])){{3}}m')
+RGB_BG_RE = re.compile(rf'{ESC}\[48;2(?:;(?:1?[0-9]?[0-9]?|2[0-4][0-9]|25[0-5])){{3}}m')
 
 
 def strip_style(text: str) -> str:
diff --git a/cmd2/argparse_completer.py b/cmd2/argparse_completer.py
index e4601307b..9bb86e9f1 100644
--- a/cmd2/argparse_completer.py
+++ b/cmd2/argparse_completer.py
@@ -92,7 +92,7 @@ def _looks_like_flag(token: str, parser: argparse.ArgumentParser) -> bool:
         return False
 
     # Flags have to start with a prefix character
-    if not token[0] in parser.prefix_chars:
+    if token[0] not in parser.prefix_chars:
         return False
 
     # If it looks like a negative number, it is not a flag unless there are negative-number-like flags
diff --git a/cmd2/clipboard.py b/cmd2/clipboard.py
index eda92bf64..454e3484c 100644
--- a/cmd2/clipboard.py
+++ b/cmd2/clipboard.py
@@ -2,6 +2,7 @@
 """
 This module provides basic ability to copy from and paste to the clipboard/pastebuffer.
 """
+
 import typing
 
 import pyperclip  # type: ignore[import]
diff --git a/cmd2/cmd2.py b/cmd2/cmd2.py
index 566d78787..1ecaadb18 100644
--- a/cmd2/cmd2.py
+++ b/cmd2/cmd2.py
@@ -21,6 +21,7 @@
 
 Git repository on GitHub at https://github.com/python-cmd2/cmd2
 """
+
 # This module has many imports, quite a few of which are only
 # infrequently utilized. To reduce the initial overhead of
 # import this module, many of these imports are lazy-loaded
@@ -2019,9 +2020,7 @@ def _determine_ap_completer_type(parser: argparse.ArgumentParser) -> Type[argpar
         :param parser: the parser to examine
         :return: type of ArgparseCompleter
         """
-        completer_type: Optional[
-            Type[argparse_completer.ArgparseCompleter]
-        ] = parser.get_ap_completer_type()  # type: ignore[attr-defined]
+        completer_type: Optional[Type[argparse_completer.ArgparseCompleter]] = parser.get_ap_completer_type()
 
         if completer_type is None:
             completer_type = argparse_completer.DEFAULT_AP_COMPLETER
@@ -5537,7 +5536,7 @@ def cmdloop(self, intro: Optional[str] = None) -> int:  # type: ignore[override]
         """
         # cmdloop() expects to be run in the main thread to support extensive use of KeyboardInterrupts throughout the
         # other built-in functions. You are free to override cmdloop, but much of cmd2's features will be limited.
-        if not threading.current_thread() is threading.main_thread():
+        if threading.current_thread() is not threading.main_thread():
             raise RuntimeError("cmdloop must be run in the main thread")
 
         # Register signal handlers
diff --git a/cmd2/command_definition.py b/cmd2/command_definition.py
index 1dcd4116f..9f713d83d 100644
--- a/cmd2/command_definition.py
+++ b/cmd2/command_definition.py
@@ -2,6 +2,7 @@
 """
 Supports the definition of commands in separate classes to be composed into cmd2.Cmd
 """
+
 from typing import (
     TYPE_CHECKING,
     Callable,
diff --git a/cmd2/decorators.py b/cmd2/decorators.py
index 601da6f97..cd9fd358c 100644
--- a/cmd2/decorators.py
+++ b/cmd2/decorators.py
@@ -1,5 +1,6 @@
 # coding=utf-8
 """Decorators for ``cmd2`` commands"""
+
 import argparse
 from typing import (
     TYPE_CHECKING,
diff --git a/cmd2/plugin.py b/cmd2/plugin.py
index affe2421d..e7e2c6863 100644
--- a/cmd2/plugin.py
+++ b/cmd2/plugin.py
@@ -1,6 +1,7 @@
 #
 # coding=utf-8
 """Classes for the cmd2 plugin system"""
+
 from dataclasses import (
     dataclass,
 )
diff --git a/cmd2/rl_utils.py b/cmd2/rl_utils.py
index f89d2b18d..b02aa73a2 100644
--- a/cmd2/rl_utils.py
+++ b/cmd2/rl_utils.py
@@ -2,6 +2,7 @@
 """
 Imports the proper Readline for the platform and provides utility functions for it
 """
+
 import sys
 from enum import (
     Enum,
diff --git a/cmd2/table_creator.py b/cmd2/table_creator.py
index c7c277562..409e7a994 100644
--- a/cmd2/table_creator.py
+++ b/cmd2/table_creator.py
@@ -5,6 +5,7 @@
 The general use case is to inherit from TableCreator to create a table class with custom formatting options.
 There are already implemented and ready-to-use examples of this below TableCreator's code.
 """
+
 import copy
 import io
 from collections import (
diff --git a/cmd2/transcript.py b/cmd2/transcript.py
index a38c19023..fdbcd0299 100644
--- a/cmd2/transcript.py
+++ b/cmd2/transcript.py
@@ -9,6 +9,7 @@
 This file contains the class necessary to make that work. This
 class is used in cmd2.py::run_transcript_tests()
 """
+
 import re
 import unittest
 from typing import (
diff --git a/cmd2/utils.py b/cmd2/utils.py
index d1e077fdc..f718d5f14 100644
--- a/cmd2/utils.py
+++ b/cmd2/utils.py
@@ -1,5 +1,6 @@
 # coding=utf-8
 """Shared utility functions"""
+
 import argparse
 import collections
 import functools
@@ -157,7 +158,7 @@ def __init__(
         :param choices_provider: function that provides choices for this argument
         :param completer: tab completion function that provides choices for this argument
         """
-        if val_type == bool:
+        if val_type is bool:
 
             def get_bool_choices(_) -> List[str]:  # type: ignore[no-untyped-def]
                 """Used to tab complete lowercase boolean values"""
@@ -1189,9 +1190,7 @@ def get_defining_class(meth: Callable[..., Any]) -> Optional[Type[Any]]:
     if isinstance(meth, functools.partial):
         return get_defining_class(meth.func)
     if inspect.ismethod(meth) or (
-        inspect.isbuiltin(meth)
-        and getattr(meth, '__self__') is not None
-        and getattr(meth.__self__, '__class__')  # type: ignore[attr-defined]
+        inspect.isbuiltin(meth) and getattr(meth, '__self__') is not None and getattr(meth.__self__, '__class__')
     ):
         for cls in inspect.getmro(meth.__self__.__class__):  # type: ignore[attr-defined]
             if meth.__name__ in cls.__dict__:
diff --git a/examples/alias_startup.py b/examples/alias_startup.py
index 72e969fcc..1ad493ffa 100755
--- a/examples/alias_startup.py
+++ b/examples/alias_startup.py
@@ -1,9 +1,10 @@
 #!/usr/bin/env python
 # coding=utf-8
 """A simple example demonstrating the following:
-    1) How to add custom command aliases using the alias command
-    2) How to run an initialization script at startup
+1) How to add custom command aliases using the alias command
+2) How to run an initialization script at startup
 """
+
 import os
 
 import cmd2
diff --git a/examples/arg_decorators.py b/examples/arg_decorators.py
index 3b02835ed..e42960b1c 100755
--- a/examples/arg_decorators.py
+++ b/examples/arg_decorators.py
@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 # coding=utf-8
 """An example demonstrating how use one of cmd2's argument parsing decorators"""
+
 import argparse
 import os
 
diff --git a/examples/argparse_completion.py b/examples/argparse_completion.py
index 506f94e26..daad63ab0 100644
--- a/examples/argparse_completion.py
+++ b/examples/argparse_completion.py
@@ -3,6 +3,7 @@
 """
 A simple example demonstrating how to integrate tab completion with argparse-based commands.
 """
+
 import argparse
 from typing import (
     Dict,
diff --git a/examples/async_printing.py b/examples/async_printing.py
index 55dff35bd..e94ee89a0 100755
--- a/examples/async_printing.py
+++ b/examples/async_printing.py
@@ -4,6 +4,7 @@
 A simple example demonstrating an application that asynchronously prints alerts, updates the prompt
 and changes the window title
 """
+
 import random
 import threading
 import time
diff --git a/examples/basic.py b/examples/basic.py
index 1f9683bf9..6ce4d2838 100755
--- a/examples/basic.py
+++ b/examples/basic.py
@@ -1,13 +1,14 @@
 #!/usr/bin/env python3
 # coding=utf-8
 """A simple example demonstrating the following:
-    1) How to add a command
-    2) How to add help for that command
-    3) Persistent history
-    4) How to run an initialization script at startup
-    5) How to add custom command aliases using the alias command
-    6) Shell-like capabilities
+1) How to add a command
+2) How to add help for that command
+3) Persistent history
+4) How to run an initialization script at startup
+5) How to add custom command aliases using the alias command
+6) Shell-like capabilities
 """
+
 import cmd2
 from cmd2 import (
     Bg,
diff --git a/examples/basic_completion.py b/examples/basic_completion.py
index febe58a3a..c713f2b0d 100755
--- a/examples/basic_completion.py
+++ b/examples/basic_completion.py
@@ -12,6 +12,7 @@
 familiar with argparse. The recommended approach for tab completing positional tokens and flags is to use
 argparse-based completion. For an example integrating tab completion with argparse, see argparse_completion.py
 """
+
 import functools
 from typing import (
     List,
diff --git a/examples/custom_parser.py b/examples/custom_parser.py
index 6e5a33b4a..94df3b054 100644
--- a/examples/custom_parser.py
+++ b/examples/custom_parser.py
@@ -2,6 +2,7 @@
 """
 Defines the CustomParser used with override_parser.py example
 """
+
 import sys
 
 from cmd2 import (
diff --git a/examples/decorator_example.py b/examples/decorator_example.py
index 75bc8dff4..ea8fd3b50 100755
--- a/examples/decorator_example.py
+++ b/examples/decorator_example.py
@@ -10,6 +10,7 @@
 all the commands in the transcript against decorator_example.py,
 verifying that the output produced matches the transcript.
 """
+
 import argparse
 from typing import (
     List,
diff --git a/examples/dynamic_commands.py b/examples/dynamic_commands.py
index eee5b8cce..82dde732d 100755
--- a/examples/dynamic_commands.py
+++ b/examples/dynamic_commands.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python3
 # coding=utf-8
-"""A simple example demonstrating how do_* commands can be created in a loop.
-"""
+"""A simple example demonstrating how do_* commands can be created in a loop."""
+
 import functools
 
 import cmd2
diff --git a/examples/environment.py b/examples/environment.py
index 3eaaa8d1d..1bb9812be 100755
--- a/examples/environment.py
+++ b/examples/environment.py
@@ -3,6 +3,7 @@
 """
 A sample application for cmd2 demonstrating customized environment parameters
 """
+
 import cmd2
 
 
diff --git a/examples/event_loops.py b/examples/event_loops.py
index 86dc01fba..e5435181a 100755
--- a/examples/event_loops.py
+++ b/examples/event_loops.py
@@ -6,6 +6,7 @@
 
 This opens up the possibility of registering cmd2 input with event loops, like asyncio, without occupying the main loop.
 """
+
 import cmd2
 
 
diff --git a/examples/example.py b/examples/example.py
index da6c3c9ff..2ff64d747 100755
--- a/examples/example.py
+++ b/examples/example.py
@@ -10,6 +10,7 @@
 the transcript against example.py, verifying that the output produced matches
 the transcript.
 """
+
 import random
 
 import cmd2
diff --git a/examples/exit_code.py b/examples/exit_code.py
index 23b172a1c..d8e538ced 100755
--- a/examples/exit_code.py
+++ b/examples/exit_code.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 # coding=utf-8
-"""A simple example demonstrating the following how to emit a non-zero exit code in your cmd2 application.
-"""
+"""A simple example demonstrating the following how to emit a non-zero exit code in your cmd2 application."""
+
 from typing import (
     List,
 )
diff --git a/examples/hello_cmd2.py b/examples/hello_cmd2.py
index 0e639e29b..a67205834 100755
--- a/examples/hello_cmd2.py
+++ b/examples/hello_cmd2.py
@@ -3,6 +3,7 @@
 """
 This is intended to be a completely bare-bones cmd2 application suitable for rapid testing and debugging.
 """
+
 from cmd2 import (
     cmd2,
 )
diff --git a/examples/help_categories.py b/examples/help_categories.py
index b2a1623fa..5c349422c 100755
--- a/examples/help_categories.py
+++ b/examples/help_categories.py
@@ -5,6 +5,7 @@
 
 It also demonstrates the effects of decorator order when it comes to argparse errors occurring.
 """
+
 import functools
 
 import cmd2
diff --git a/examples/initialization.py b/examples/initialization.py
index 292756d9d..426a5a4a2 100755
--- a/examples/initialization.py
+++ b/examples/initialization.py
@@ -1,17 +1,18 @@
 #!/usr/bin/env python3
 # coding=utf-8
 """A simple example cmd2 application demonstrating the following:
-     1) Colorizing/stylizing output
-     2) Using multiline commands
-     3) Persistent history
-     4) How to run an initialization script at startup
-     5) How to group and categorize commands when displaying them in help
-     6) Opting-in to using the ipy command to run an IPython shell
-     7) Allowing access to your application in py and ipy
-     8) Displaying an intro banner upon starting your application
-     9) Using a custom prompt
-    10) How to make custom attributes settable at runtime
+ 1) Colorizing/stylizing output
+ 2) Using multiline commands
+ 3) Persistent history
+ 4) How to run an initialization script at startup
+ 5) How to group and categorize commands when displaying them in help
+ 6) Opting-in to using the ipy command to run an IPython shell
+ 7) Allowing access to your application in py and ipy
+ 8) Displaying an intro banner upon starting your application
+ 9) Using a custom prompt
+10) How to make custom attributes settable at runtime
 """
+
 import cmd2
 from cmd2 import (
     Bg,
diff --git a/examples/migrating.py b/examples/migrating.py
index fab40d25f..22efadab9 100755
--- a/examples/migrating.py
+++ b/examples/migrating.py
@@ -3,6 +3,7 @@
 """
 A sample application for cmd which can be used to show how to migrate to cmd2.
 """
+
 import cmd
 import random
 
diff --git a/examples/modular_commands/commandset_basic.py b/examples/modular_commands/commandset_basic.py
index ab52a326a..a4b7582f5 100644
--- a/examples/modular_commands/commandset_basic.py
+++ b/examples/modular_commands/commandset_basic.py
@@ -2,6 +2,7 @@
 """
 A simple example demonstrating a loadable command set
 """
+
 from typing import (
     List,
 )
diff --git a/examples/modular_commands/commandset_custominit.py b/examples/modular_commands/commandset_custominit.py
index e24ac291c..a3f4f59ad 100644
--- a/examples/modular_commands/commandset_custominit.py
+++ b/examples/modular_commands/commandset_custominit.py
@@ -2,6 +2,7 @@
 """
 A simple example demonstrating a loadable command set
 """
+
 from cmd2 import (
     Cmd,
     CommandSet,
diff --git a/examples/modular_commands_main.py b/examples/modular_commands_main.py
index 3aeb8b2a2..74483987b 100644
--- a/examples/modular_commands_main.py
+++ b/examples/modular_commands_main.py
@@ -4,6 +4,7 @@
 A complex example demonstrating a variety of methods to load CommandSets using a mix of command decorators
 with examples of how to integrate tab completion with argparse-based commands.
 """
+
 import argparse
 from typing import (
     Iterable,
diff --git a/examples/modular_subcommands.py b/examples/modular_subcommands.py
index 082903fb1..14d117814 100644
--- a/examples/modular_subcommands.py
+++ b/examples/modular_subcommands.py
@@ -10,6 +10,7 @@
 The `load` and `unload` command will load and unload the CommandSets. The available top level commands as well as
 subcommands to the `cut` command will change depending on which CommandSets are loaded.
 """
+
 import argparse
 
 import cmd2
diff --git a/examples/paged_output.py b/examples/paged_output.py
index afed8a6e7..0f7173b2e 100755
--- a/examples/paged_output.py
+++ b/examples/paged_output.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 # coding=utf-8
-"""A simple example demonstrating the using paged output via the ppaged() method.
-"""
+"""A simple example demonstrating the using paged output via the ppaged() method."""
+
 import os
 from typing import (
     List,
diff --git a/examples/persistent_history.py b/examples/persistent_history.py
index 330e35379..ab4b89f2b 100755
--- a/examples/persistent_history.py
+++ b/examples/persistent_history.py
@@ -5,6 +5,7 @@
 This will allow end users of your cmd2-based application to use the arrow keys and Ctrl+r in a manner which persists
 across invocations of your cmd2 application.  This can make it much easier for them to use your application.
 """
+
 import cmd2
 
 
diff --git a/examples/python_scripting.py b/examples/python_scripting.py
index 397870858..e2403c0c2 100755
--- a/examples/python_scripting.py
+++ b/examples/python_scripting.py
@@ -20,6 +20,7 @@
 This application and the "examples/scripts/conditional.py" script serve as an
 example for one way in which this can be done.
 """
+
 import os
 
 import cmd2
diff --git a/examples/read_input.py b/examples/read_input.py
index 3a13e9d3a..bfc43380b 100644
--- a/examples/read_input.py
+++ b/examples/read_input.py
@@ -3,6 +3,7 @@
 """
 A simple example demonstrating the various ways to call cmd2.Cmd.read_input() for input history and tab completion
 """
+
 from typing import (
     List,
 )
diff --git a/examples/remove_settable.py b/examples/remove_settable.py
index a7b871266..fad671cbe 100755
--- a/examples/remove_settable.py
+++ b/examples/remove_settable.py
@@ -3,6 +3,7 @@
 """
 A sample application for cmd2 demonstrating how to remove one of the built-in runtime settable parameters.
 """
+
 import cmd2
 
 
diff --git a/examples/scripts/conditional.py b/examples/scripts/conditional.py
index eb7106958..dd3adcca0 100644
--- a/examples/scripts/conditional.py
+++ b/examples/scripts/conditional.py
@@ -10,6 +10,7 @@
 Note: The "app" function is defined within the cmd2 embedded Python environment and in there "self" is your cmd2
 application instance. Note: self only exists in this environment if self_in_py is True.
 """
+
 import os
 import sys
 
diff --git a/examples/scripts/script.py b/examples/scripts/script.py
index 5195b8cc9..339fbf2c8 100644
--- a/examples/scripts/script.py
+++ b/examples/scripts/script.py
@@ -3,4 +3,5 @@
 """
 Trivial example of a Python script which can be run inside a cmd2 application.
 """
+
 print("This is a python script running ...")
diff --git a/examples/table_creation.py b/examples/table_creation.py
index 78b3a0f08..852f2d84d 100755
--- a/examples/table_creation.py
+++ b/examples/table_creation.py
@@ -1,6 +1,7 @@
 #!/usr/bin/env python
 # coding=utf-8
 """Examples of using the cmd2 table creation API"""
+
 import functools
 import sys
 from typing import (
diff --git a/examples/unicode_commands.py b/examples/unicode_commands.py
index 0a7c5ac74..6c76a76e7 100755
--- a/examples/unicode_commands.py
+++ b/examples/unicode_commands.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 # coding=utf-8
-"""A simple example demonstrating support for unicode command names.
-"""
+"""A simple example demonstrating support for unicode command names."""
+
 import math
 
 import cmd2
diff --git a/plugins/ext_test/tasks.py b/plugins/ext_test/tasks.py
index 6370af0c1..640117863 100644
--- a/plugins/ext_test/tasks.py
+++ b/plugins/ext_test/tasks.py
@@ -8,6 +8,7 @@
     - wheel >= 0.31.0
     - setuptools >= 39.1.0
 """
+
 import os
 import pathlib
 import shutil
diff --git a/plugins/tasks.py b/plugins/tasks.py
index a22eb310d..4ef83255d 100644
--- a/plugins/tasks.py
+++ b/plugins/tasks.py
@@ -8,6 +8,7 @@
     - wheel >= 0.31.0
     - setuptools >= 39.1.0
 """
+
 import invoke
 
 from plugins.ext_test import (
diff --git a/pyproject.toml b/pyproject.toml
index de8bb4063..50aab79d4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -25,3 +25,172 @@ exclude = '''
   | htmlcov
 )/
 '''
+
+[tool.ruff]
+# Exclude a variety of commonly ignored directories.
+exclude = [
+    ".bzr",
+    ".direnv",
+    ".eggs",
+    ".git",
+    ".git-rewrite",
+    ".hg",
+    ".ipynb_checkpoints",
+    ".mypy_cache",
+    ".nox",
+    ".pants.d",
+    ".pyenv",
+    ".pytest_cache",
+    ".pytype",
+    ".ruff_cache",
+    ".svn",
+    ".tox",
+    ".venv",
+    ".vscode",
+    "__pypackages__",
+    "_build",
+    "buck-out",
+    "build",
+    "dist",
+    "node_modules",
+    "site-packages",
+    "venv",
+]
+
+# Same as Black.
+line-length = 127
+indent-width = 4
+
+# Assume Python 3.13
+target-version = "py313"
+output-format = "full"
+
+[tool.ruff.lint]
+# Enable Pyflakes (`F`) and a subset of the pycodestyle (`E`)  codes by default.
+# Unlike Flake8, Ruff doesn't enable pycodestyle warnings (`W`) or
+# McCabe complexity (`C901`) by default.
+select = [
+    # https://beta.ruff.rs/docs/rules
+    #    "A", # flake8-builtins
+    #    "ARG", # flake8-unused-arguments
+    "ASYNC", # flake8-async
+    #    "B", # flake8-bugbear
+    #    "BLE", # flake8-blind-except
+    #    "C4", # flake8-comprehensions
+    "C90", # McCabe cyclomatic complexity
+    "DJ", # flake8-django
+    #    "DTZ", # flake8-datetimez
+    "E", # pycodestyle
+    #    "EM", # flake8-errmsg
+    #    "EXE", # flake8-executable
+    "F", # Pyflakes
+    "FA", # flake8-future-annotations
+    #    "FLY", # flynt
+    "G", # flake8-logging-format
+    #    "I", # isort
+    "ICN", # flake8-import-conventions
+    #    "INP", # flake8-no-pep420
+    "INT", # flake8-gettext
+    #    "ISC", # flake8-implicit-str-concat
+    #    "N", # pep8-naming
+    "NPY", # NumPy-specific rules
+    "PD", # pandas-vet
+    #    "PGH", # pygrep-hooks
+    #    "PIE", # flake8-pie
+    #    "PL", # Pylint
+    #    "PT", # flake8-pytest-style
+    #    "PYI", # flake8-pyi
+    "RSE", # flake8-raise
+    #    "RUF", # Ruff-specific rules
+    #    "S", # flake8-bandit
+    #    "SIM", # flake8-simplify
+    #    "SLF", # flake8-self
+    #    "T10", # flake8-debugger
+    #    "TD", # flake8-todos
+    #    "TID", # flake8-tidy-imports
+    #    "UP", # pyupgrade
+    #    "W", # pycodestyle
+    #    "YTT", # flake8-2020
+    # "ANN",  # flake8-annotations  # FIX ME?
+    # "COM",  # flake8-commas
+    # "D",    # pydocstyle -- FIX ME?
+    # "ERA",  # eradicate -- DO NOT FIX
+    # "FBT",  # flake8-boolean-trap  # FIX ME
+    # "PTH",  # flake8-use-pathlib  # FIX ME
+    # "Q",    # flake8-quotes
+    # "RET",  # flake8-return  # FIX ME?
+    # "T20",  # flake8-print
+    # "TCH",  # flake8-type-checking
+    # "TRY",  # tryceratops
+]
+ignore = [
+    # `ruff rule S101` for a description of that rule
+    "B904", # Within an `except` clause, raise exceptions with `raise ... from err` -- FIX ME
+    "B905", # `zip()` without an explicit `strict=` parameter -- FIX ME
+    "E501", # Line too long
+    "EM101", # Exception must not use a string literal, assign to variable first
+    "EXE001", # Shebang is present but file is not executable -- DO NOT FIX
+    "G004", # Logging statement uses f-string
+    "PLC1901", # `{}` can be simplified to `{}` as an empty string is falsey
+    "PLW060", # Using global for `{name}` but no assignment is done -- DO NOT FIX
+    "PLW2901", # PLW2901: Redefined loop variable -- FIX ME
+    "PT011", # `pytest.raises(Exception)` is too broad, set the `match` parameter or use a more specific exception
+    "PT018", # Assertion should be broken down into multiple parts
+    "S101", # Use of `assert` detected -- DO NOT FIX
+    "S311", # Standard pseudo-random generators are not suitable for cryptographic purposes -- FIX ME
+    "SLF001", # Private member accessed: `_Iterator` -- FIX ME
+    "UP038", # Use `X | Y` in `{}` call instead of `(X, Y)` -- DO NOT FIX
+]
+
+# Allow fix for all enabled rules (when `--fix`) is provided.
+fixable = ["ALL"]
+unfixable = []
+
+# Allow unused variables when underscore-prefixed.
+dummy-variable-rgx = "^(_+|(_+[a-zA-Z0-9_]*[a-zA-Z0-9]+?))$"
+
+mccabe.max-complexity = 49
+
+per-file-ignores."cmd2/__init__.py" = [
+    "E402", # Module level import not at top of file
+    "F401", # Unused import
+]
+
+per-file-ignores."examples/override_parser.py" = [
+    "E402", # Module level import not at top of file
+]
+
+per-file-ignores."examples/scripts/*.py" = [
+    "F821", # Undefined name `app`
+]
+
+per-file-ignores."tests/pyscript/*.py" = [
+    "F821", # Undefined name `app`
+]
+
+[tool.ruff.format]
+# Like Black, use double quotes for strings.
+quote-style = "preserve"
+
+# Like Black, indent with spaces, rather than tabs.
+indent-style = "space"
+
+# Like Black, respect magic trailing commas.
+skip-magic-trailing-comma = false
+
+# Like Black, automatically detect the appropriate line ending.
+line-ending = "auto"
+
+# Enable auto-formatting of code examples in docstrings. Markdown,
+# reStructuredText code/literal blocks and doctests are all supported.
+#
+# This is currently disabled by default, but it is planned for this
+# to be opt-out in the future.
+docstring-code-format = false
+
+# Set the line length limit used when formatting code snippets in
+# docstrings.
+#
+# This only has an effect when the `docstring-code-format` setting is
+# enabled.
+docstring-code-line-length = "dynamic"
diff --git a/setup.py b/setup.py
index 749f254ab..047015e7d 100755
--- a/setup.py
+++ b/setup.py
@@ -3,6 +3,7 @@
 """
 Setuptools setup file, used to install or test 'cmd2'
 """
+
 import codecs
 
 from setuptools import (
diff --git a/tasks.py b/tasks.py
index e0eb16a0f..4c0a32dcd 100644
--- a/tasks.py
+++ b/tasks.py
@@ -8,6 +8,7 @@
     - wheel >= 0.31.0
     - setuptools >= 39.1.0
 """
+
 import os
 import pathlib
 import re
@@ -366,3 +367,14 @@ def format(context):
 
 
 namespace.add_task(format)
+
+
+# ruff extremely fast Python linter and formatter written in Rust
+@invoke.task()
+def ruff(context):
+    """Run ruff linter and formatter"""
+    with context.cd(TASK_ROOT_STR):
+        context.run("ruff check && ruff format --check")
+
+
+namespace.add_task(ruff)
diff --git a/tests/conftest.py b/tests/conftest.py
index 35ff2e89d..644ae7cca 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -2,6 +2,7 @@
 """
 Cmd2 unit/functional testing
 """
+
 import argparse
 import sys
 from contextlib import (
diff --git a/tests/pyscript/raises_exception.py b/tests/pyscript/raises_exception.py
index 738edaf28..ab4670890 100644
--- a/tests/pyscript/raises_exception.py
+++ b/tests/pyscript/raises_exception.py
@@ -3,4 +3,5 @@
 """
 Example demonstrating what happens when a Python script raises an exception
 """
+
 1 + 'blue'
diff --git a/tests/pyscript/recursive.py b/tests/pyscript/recursive.py
index b88ba5a52..206f356cb 100644
--- a/tests/pyscript/recursive.py
+++ b/tests/pyscript/recursive.py
@@ -4,6 +4,7 @@
 """
 Example demonstrating that calling run_pyscript recursively inside another Python script isn't allowed
 """
+
 import os
 import sys
 
diff --git a/tests/script.py b/tests/script.py
index 5195b8cc9..339fbf2c8 100644
--- a/tests/script.py
+++ b/tests/script.py
@@ -3,4 +3,5 @@
 """
 Trivial example of a Python script which can be run inside a cmd2 application.
 """
+
 print("This is a python script running ...")
diff --git a/tests/test_ansi.py b/tests/test_ansi.py
index a2c49702a..65ec68a9d 100644
--- a/tests/test_ansi.py
+++ b/tests/test_ansi.py
@@ -3,6 +3,7 @@
 """
 Unit testing for cmd2/ansi.py module
 """
+
 import pytest
 
 from cmd2 import (
diff --git a/tests/test_argparse.py b/tests/test_argparse.py
index 19512aff9..7a682c5ce 100644
--- a/tests/test_argparse.py
+++ b/tests/test_argparse.py
@@ -3,6 +3,7 @@
 """
 Cmd2 testing for argument parsing
 """
+
 import argparse
 from typing import (
     Optional,
@@ -404,7 +405,7 @@ def test_add_another_subcommand(subcommand_app):
     to add_parser() write the correct prog value to the parser being added.
     """
     base_parser = subcommand_app._command_parsers.get('base')
-    subcommand_parser = find_subcommand(subcommand_app._command_parsers.get('base'), [])
+    find_subcommand(subcommand_app._command_parsers.get('base'), [])
     for sub_action in base_parser._actions:
         if isinstance(sub_action, argparse._SubParsersAction):
             new_parser = sub_action.add_parser('new_sub', help='stuff')
@@ -449,16 +450,16 @@ def test_unittest_mock():
 
     with mock.patch.object(ArgparseApp, 'namespace_provider'):
         with pytest.raises(CommandSetRegistrationError):
-            app = ArgparseApp()
+            ArgparseApp()
 
     with mock.patch.object(ArgparseApp, 'namespace_provider', spec=True):
-        app = ArgparseApp()
+        ArgparseApp()
 
     with mock.patch.object(ArgparseApp, 'namespace_provider', spec_set=True):
-        app = ArgparseApp()
+        ArgparseApp()
 
     with mock.patch.object(ArgparseApp, 'namespace_provider', autospec=True):
-        app = ArgparseApp()
+        ArgparseApp()
 
 
 def test_pytest_mock_invalid(mocker):
@@ -468,7 +469,7 @@ def test_pytest_mock_invalid(mocker):
 
     mocker.patch.object(ArgparseApp, 'namespace_provider')
     with pytest.raises(CommandSetRegistrationError):
-        app = ArgparseApp()
+        ArgparseApp()
 
 
 @pytest.mark.parametrize(
@@ -481,4 +482,4 @@ def test_pytest_mock_invalid(mocker):
 )
 def test_pytest_mock_valid(mocker, spec_param):
     mocker.patch.object(ArgparseApp, 'namespace_provider', **spec_param)
-    app = ArgparseApp()
+    ArgparseApp()
diff --git a/tests/test_argparse_completer.py b/tests/test_argparse_completer.py
index a764a45f5..a2fb89eb1 100644
--- a/tests/test_argparse_completer.py
+++ b/tests/test_argparse_completer.py
@@ -3,6 +3,7 @@
 """
 Unit/functional testing for argparse completer in cmd2
 """
+
 import argparse
 import numbers
 from typing import (
diff --git a/tests/test_argparse_custom.py b/tests/test_argparse_custom.py
index 768cac0bc..a3f85558c 100644
--- a/tests/test_argparse_custom.py
+++ b/tests/test_argparse_custom.py
@@ -2,6 +2,7 @@
 """
 Unit/functional testing for argparse customizations in cmd2
 """
+
 import argparse
 
 import pytest
diff --git a/tests/test_cmd2.py b/tests/test_cmd2.py
index d76c0bbfc..96d666611 100755
--- a/tests/test_cmd2.py
+++ b/tests/test_cmd2.py
@@ -3,10 +3,10 @@
 """
 Cmd2 unit/functional testing
 """
+
 import builtins
 import io
 import os
-import readline
 import signal
 import sys
 import tempfile
@@ -149,7 +149,7 @@ def test_base_shortcuts(base_app):
 
 def test_command_starts_with_shortcut():
     with pytest.raises(ValueError) as excinfo:
-        app = cmd2.Cmd(shortcuts={'help': 'fake'})
+        cmd2.Cmd(shortcuts={'help': 'fake'})
     assert "Invalid command name 'help'" in str(excinfo.value)
 
 
@@ -813,9 +813,9 @@ def test_get_paste_buffer_exception(base_app, mocker, capsys):
 
 
 def test_allow_clipboard_initializer(base_app):
-    assert base_app.allow_clipboard == True
+    assert base_app.allow_clipboard is True
     noclipcmd = cmd2.Cmd(allow_clipboard=False)
-    assert noclipcmd.allow_clipboard == False
+    assert noclipcmd.allow_clipboard is False
 
 
 # if clipboard access is not allowed, cmd2 should check that first
diff --git a/tests/test_completion.py b/tests/test_completion.py
index 2eebaaebe..27b974af4 100755
--- a/tests/test_completion.py
+++ b/tests/test_completion.py
@@ -6,6 +6,7 @@
 These are primarily tests related to readline completer functions which handle tab completion of cmd2/cmd commands,
 file system paths, and shell commands.
 """
+
 import enum
 import os
 import sys
@@ -274,7 +275,7 @@ def test_cmd2_help_completion_nomatch(cmd2_app):
 def test_set_allow_style_completion(cmd2_app):
     """Confirm that completing allow_style presents AllowStyle strings"""
     text = ''
-    line = 'set allow_style'.format(text)
+    line = 'set allow_style'.format()
     endidx = len(line)
     begidx = endidx - len(text)
 
@@ -288,7 +289,7 @@ def test_set_allow_style_completion(cmd2_app):
 def test_set_bool_completion(cmd2_app):
     """Confirm that completing a boolean Settable presents true and false strings"""
     text = ''
-    line = 'set debug'.format(text)
+    line = 'set debug'.format()
     endidx = len(line)
     begidx = endidx - len(text)
 
@@ -1331,7 +1332,7 @@ def test_help_subcommand_completion_nomatch_scu(scu_app):
     begidx = endidx - len(text)
 
     first_match = complete_tester(text, line, begidx, endidx, scu_app)
-    assert first_match == None
+    assert first_match is None
 
 
 def test_subcommand_tab_completion_scu(scu_app):
diff --git a/tests/test_history.py b/tests/test_history.py
index 38b539c68..1a3bd744b 100755
--- a/tests/test_history.py
+++ b/tests/test_history.py
@@ -3,6 +3,7 @@
 """
 Test history functions of cmd2
 """
+
 import os
 import tempfile
 from unittest import (
@@ -478,7 +479,7 @@ def test_history_item_instantiate():
         Statement,
     )
 
-    statement = Statement(
+    Statement(
         'history',
         raw='help history',
         command='help',
@@ -898,7 +899,7 @@ def test_history_file_is_directory(capsys):
 def test_history_can_create_directory(mocker):
     # Mock out atexit.register so the persistent file doesn't written when this function
     # exists because we will be deleting the directory it needs to go to.
-    mock_register = mocker.patch('atexit.register')
+    mocker.patch('atexit.register')
 
     # Create a temp path for us to use and let it get deleted
     with tempfile.TemporaryDirectory() as test_dir:
diff --git a/tests/test_parsing.py b/tests/test_parsing.py
index 37a93ba26..83df13cf5 100755
--- a/tests/test_parsing.py
+++ b/tests/test_parsing.py
@@ -3,6 +3,7 @@
 """
 Test the parsing logic in parsing.py
 """
+
 import dataclasses
 
 import pytest
diff --git a/tests/test_plugin.py b/tests/test_plugin.py
index 61b140ab0..eb91892c4 100644
--- a/tests/test_plugin.py
+++ b/tests/test_plugin.py
@@ -3,6 +3,7 @@
 """
 Test plugin infrastructure and hooks.
 """
+
 import argparse
 import sys
 from unittest import (
diff --git a/tests/test_run_pyscript.py b/tests/test_run_pyscript.py
index 3732e57e1..594a30b75 100644
--- a/tests/test_run_pyscript.py
+++ b/tests/test_run_pyscript.py
@@ -3,6 +3,7 @@
 """
 Unit/functional testing for run_pytest in cmd2
 """
+
 import builtins
 import os
 from unittest import (
diff --git a/tests/test_table_creator.py b/tests/test_table_creator.py
index 585ed62ab..fbbdfbc4a 100644
--- a/tests/test_table_creator.py
+++ b/tests/test_table_creator.py
@@ -3,6 +3,7 @@
 """
 Unit testing for cmd2/table_creator.py module
 """
+
 import pytest
 
 from cmd2 import (
diff --git a/tests/test_transcript.py b/tests/test_transcript.py
index ed193a00c..986221ff2 100644
--- a/tests/test_transcript.py
+++ b/tests/test_transcript.py
@@ -3,6 +3,7 @@
 """
 Cmd2 functional testing based on transcript
 """
+
 import os
 import random
 import re
diff --git a/tests/test_utils.py b/tests/test_utils.py
index e8198d4be..2779a38b8 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -3,6 +3,7 @@
 """
 Unit testing for cmd2/utils.py module.
 """
+
 import os
 import signal
 import sys
diff --git a/tests/test_utils_defining_class.py b/tests/test_utils_defining_class.py
index 5d667678a..8b6ede8bf 100644
--- a/tests/test_utils_defining_class.py
+++ b/tests/test_utils_defining_class.py
@@ -3,6 +3,7 @@
 """
 Unit testing for get_defining_class in cmd2/utils.py module.
 """
+
 import functools
 
 import cmd2.utils as cu
@@ -23,7 +24,8 @@ def func_with_overrides(self):
     def child_function(self):
         pass
 
-    lambda1 = lambda: 1
+    def lambda1():
+        return 1
 
     lambda2 = (lambda: lambda: 2)()
 
diff --git a/tests_isolated/test_commandset/conftest.py b/tests_isolated/test_commandset/conftest.py
index 41d5b6a4d..c8c6d34b4 100644
--- a/tests_isolated/test_commandset/conftest.py
+++ b/tests_isolated/test_commandset/conftest.py
@@ -2,6 +2,7 @@
 """
 Cmd2 unit/functional testing
 """
+
 import sys
 from contextlib import (
     redirect_stderr,
diff --git a/tests_isolated/test_commandset/test_categories.py b/tests_isolated/test_commandset/test_categories.py
index 71f1db8e2..986ae3fa9 100644
--- a/tests_isolated/test_commandset/test_categories.py
+++ b/tests_isolated/test_commandset/test_categories.py
@@ -3,6 +3,7 @@
 """
 Simple example demonstrating basic CommandSet usage.
 """
+
 from typing import (
     Any,
 )
diff --git a/tests_isolated/test_commandset/test_commandset.py b/tests_isolated/test_commandset/test_commandset.py
index e400437b1..c7293d411 100644
--- a/tests_isolated/test_commandset/test_commandset.py
+++ b/tests_isolated/test_commandset/test_commandset.py
@@ -963,7 +963,7 @@ def cut_banana(self, ns: argparse.Namespace):
             self.poutput('cutting banana: ' + ns.direction)
 
     with pytest.raises(CommandSetRegistrationError):
-        app = BadSubcommandApp()
+        BadSubcommandApp()
 
 
 def test_commandset_settables():