diff --git a/.flake8 b/.flake8
deleted file mode 100644
index eb0260b03..000000000
--- a/.flake8
+++ /dev/null
@@ -1,178 +0,0 @@
-[flake8]
-
-ignore =
-  # unnecessary list comprehension; A generator only better than a list
-  # comprehension if we don't always need to iterate through all items in
-  # the generator (based on the use case).
-  C407,
-  # The following codes belong to pycodestyle, and overlap with black:
-  # indentation contains mixed spaces and tabs
-  E101,
-  # indentation is not a multiple of four
-  E111,
-  # expected an indented block
-  E112,
-  # unexpected indentation
-  E113,
-  # indentation is not a multiple of four (comment)
-  E114,
-  # expected an indented block (comment)
-  E115,
-  # unexpected indentation (comment)
-  E116,
-  # continuation line under-indented for hanging indent
-  E121,
-  # continuation line missing indentation or outdented
-  E122,
-  # closing bracket does not match indentation of opening bracket’s line
-  E123,
-  # closing bracket does not match visual indentation
-  E124,
-  # continuation line with same indent as next logical line
-  E125,
-  # continuation line over-indented for hanging indent
-  E126,
-  # continuation line over-indented for visual indent; is harmless
-  # (over-indent is visually unambiguous) and currently generates too
-  # many warnings for existing code.
-  E127,
-         
-  # continuation line under-indented for visual indent
-  E128,
-  # visually indented line with same indent as next logical line
-  E129,
-  # continuation line unaligned for hanging indent
-  E131,
-  # closing bracket is missing indentation
-  E133,
-  # whitespace after ‘(‘
-  E201,
-  # whitespace before ‘)’
-  E202,
-  # whitespace before ‘:’; this warning is invalid for slices
-  E203,
-  # whitespace before ‘(‘
-  E211,
-  # multiple spaces before operator
-  E221,
-  # multiple spaces after operator
-  E222,
-  # tab before operator
-  E223,
-  # tab after operator
-  E224,
-  # missing whitespace around operator
-  E225,
-  # missing whitespace around arithmetic operator
-  E226,
-  # missing whitespace around bitwise or shift operator
-  E227,
-  # missing whitespace around modulo operator
-  E228,
-  # missing whitespace after ‘,’, ‘;’, or ‘:’
-  E231,
-  # multiple spaces after ‘,’
-  E241,
-  # tab after ‘,’
-  E242,
-  # unexpected spaces around keyword / parameter equals
-  E251,
-  # at least two spaces before inline comment
-  E261,
-  # inline comment should start with ‘# ‘
-  E262,
-  # block comment should start with ‘# ‘
-  E265,
-  # too many leading ‘#’ for block comment
-  E266,
-  # multiple spaces after keyword
-  E271,
-  # multiple spaces before keyword
-  E272,
-  # tab after keyword
-  E273,
-  # tab before keyword
-  E274,
-  # missing whitespace after keyword
-  E275,
-  # expected 1 blank line, found 0
-  E301,
-  # expected 2 blank lines, found 0
-  E302,
-  # too many blank lines (3)
-  E303,
-  # blank lines found after function decorator
-  E304,
-  # expected 2 blank lines after end of function or class
-  E305,
-  # expected 1 blank line before a nested definition
-  E306,
-  # multiple imports on one line
-  E401,
-  # line too long (> 79 characters)
-  E501,
-  # the backslash is redundant between brackets
-  E502,
-  # multiple statements on one line (colon)
-  E701,
-  # multiple statements on one line (semicolon)
-  E702,
-  # statement ends with a semicolon
-  E703,
-  # multiple statements on one line (def)
-  E704,
-  # These are pycodestyle lints that black doesn't catch:
-  # E711,  # comparison to None should be ‘if cond is None:’
-  # E712,  # comparison to True should be ‘if cond is True:’ or ‘if cond:’
-  # E713,  # test for membership should be ‘not in’
-  # E714,  # test for object identity should be ‘is not’
-  # E721,  # do not compare types, use ‘isinstance()’
-  # E722,  # do not use bare except, specify exception instead
-  # E731,  # do not assign a lambda expression, use a def
-  # E741,  # do not use variables named ‘l’, ‘O’, or ‘I’
-  # E742,  # do not define classes named ‘l’, ‘O’, or ‘I’
-  # E743,  # do not define functions named ‘l’, ‘O’, or ‘I’
-  # I think these are internal to pycodestyle?
-  # E901,  # SyntaxError or IndentationError
-  # E902,  # IOError
-  # isn't aware of type-only imports, results in false-positives
-  F811,
-  # indentation contains tabs
-  W191,
-  # trailing whitespace
-  W291,
-  # no newline at end of file
-  W292,
-  # blank line contains whitespace
-  W293,
-  # blank line at end of file
-  W391,
-  # line break before binary operator; binary operator in a new line is
-  # the standard
-  W503,
-  # line break after binary operator
-  W504,
-  # not part of PEP8; doc line too long (> 79 characters)
-  W505,
-  # These are pycodestyle lints that black doesn't catch:
-  # W601,  # .has_key() is deprecated, use ‘in’
-  # W602,  # deprecated form of raising exception
-  # W603,  # ‘<>’ is deprecated, use ‘!=’
-  # W604,  # backticks are deprecated, use ‘repr()’
-  # W605,  # invalid escape sequence ‘x’
-  # W606,  # ‘async’ and ‘await’ are reserved keywords starting with Python 3.7
-
-# We should've silenced all of Flake8's line-length related lints, in favor of
-# Black. However, let's just set this to a large value just to be safe, in case
-# we accidentally left in a line-length related lint rule. If we don't set
-# anything, it defaults to 79, which is also wrong.
-max-line-length = 999
-
-exclude =
-  .pyre,
-  __pycache__,
-  .tox,
-  native,
-
-max-complexity = 12
-
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 9af09650b..7858b2d7c 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -31,7 +31,7 @@ disclosure of security bugs. In those cases, please go through the process
 outlined on that page and do not file a public issue.
 
 ## Coding Style
-We use flake8 and ufmt to enforce coding style.
+We use Ruff to enforce coding style.
 
 ## License
 By contributing to LibCST, you agree that your contributions will be licensed
diff --git a/README.rst b/README.rst
index 5957ba3e8..ef0732798 100644
--- a/README.rst
+++ b/README.rst
@@ -183,7 +183,7 @@ We have multiple linters, including copyright checks and
 
     hatch run lint
 
-We use `ufmt <https://ufmt.omnilib.dev/en/stable/>`_ to format code. To format
+We use `ruff <https://beta.ruff.rs/>`_ to format code. To format
 changes to be conformant, run the following in the root:
 
 .. code-block:: shell
diff --git a/docs/source/conf.py b/docs/source/conf.py
index c210fc1d8..220f31326 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -196,6 +196,7 @@
 # If true, `todo` and `todoList` produce output, else they produce nothing.
 todo_include_todos = True
 
+
 # -- autodoc customization
 def strip_class_signature(app, what, name, obj, options, signature, return_annotation):
     if what == "class":
diff --git a/libcst/_nodes/base.py b/libcst/_nodes/base.py
index d9689f8f8..61161923d 100644
--- a/libcst/_nodes/base.py
+++ b/libcst/_nodes/base.py
@@ -341,7 +341,7 @@ def deep_clone(self: _CSTNodeSelfT) -> _CSTNodeSelfT:
         True
         """
         cloned_fields: Dict[str, object] = {}
-        for field in fields(self):
+        for field in fields(self):  # noqa: F402
             key = field.name
             if key[0] == "_":
                 continue
diff --git a/libcst/_nodes/tests/test_with.py b/libcst/_nodes/tests/test_with.py
index 517ce357f..ef9245a81 100644
--- a/libcst/_nodes/tests/test_with.py
+++ b/libcst/_nodes/tests/test_with.py
@@ -331,5 +331,6 @@ def test_adding_parens(self) -> None:
         )
         module = cst.Module([])
         self.assertEqual(
-            module.code_for_node(node), ("with ( foo(),\n" "bar(), ): pass\n")  # noqa
+            module.code_for_node(node),
+            ("with ( foo(),\n" "bar(), ): pass\n"),  # noqa
         )
diff --git a/libcst/_parser/conversions/params.py b/libcst/_parser/conversions/params.py
index 9ac7f1d16..311ea02f3 100644
--- a/libcst/_parser/conversions/params.py
+++ b/libcst/_parser/conversions/params.py
@@ -102,7 +102,7 @@ def convert_argslist(  # noqa: C901
     kwonly_params: List[Param] = []
     star_kwarg: Optional[Param] = None
 
-    def add_param(
+    def add_param(  # noqa: C901
         current_param: Optional[List[Param]], param: Union[Param, ParamStar]
     ) -> Optional[List[Param]]:
         nonlocal star_arg
diff --git a/libcst/_typed_visitor.py b/libcst/_typed_visitor.py
index 7e1d1c420..cb64ce352 100644
--- a/libcst/_typed_visitor.py
+++ b/libcst/_typed_visitor.py
@@ -12,7 +12,6 @@
 from libcst._removal_sentinel import RemovalSentinel
 from libcst._typed_visitor_base import mark_no_op
 
-
 if TYPE_CHECKING:
     from libcst._nodes.expression import (  # noqa: F401
         Annotation,
@@ -75,7 +74,9 @@
         UnaryOperation,
         Yield,
     )
-    from libcst._nodes.module import Module  # noqa: F401
+    from libcst._nodes.module import (  # noqa: F401
+        Module,
+    )
     from libcst._nodes.op import (  # noqa: F401
         Add,
         AddAssign,
diff --git a/libcst/_typed_visitor_base.py b/libcst/_typed_visitor_base.py
index de751a158..5a218347e 100644
--- a/libcst/_typed_visitor_base.py
+++ b/libcst/_typed_visitor_base.py
@@ -5,7 +5,6 @@
 
 from typing import Any, Callable, cast, TypeVar
 
-
 # pyre-fixme[24]: Generic type `Callable` expects 2 type parameters.
 F = TypeVar("F", bound=Callable)
 
diff --git a/libcst/codegen/generate.py b/libcst/codegen/generate.py
index 92f131765..3e075c29d 100644
--- a/libcst/codegen/generate.py
+++ b/libcst/codegen/generate.py
@@ -26,7 +26,7 @@
 
 def format_file(fname: str) -> None:
     subprocess.check_call(
-        ["ufmt", "format", fname],
+        ["ruff", "format", fname],
         stdout=subprocess.DEVNULL,
         stderr=subprocess.DEVNULL,
     )
diff --git a/libcst/codemod/commands/add_trailing_commas.py b/libcst/codemod/commands/add_trailing_commas.py
index 2f33a4bd7..a80472a7e 100644
--- a/libcst/codemod/commands/add_trailing_commas.py
+++ b/libcst/codemod/commands/add_trailing_commas.py
@@ -10,7 +10,6 @@
 import libcst as cst
 from libcst.codemod import CodemodContext, VisitorBasedCodemodCommand
 
-
 presets_per_formatter: Dict[str, Dict[str, int]] = {
     "black": {
         "parameter_count": 1,
diff --git a/libcst/codemod/visitors/_apply_type_annotations.py b/libcst/codemod/visitors/_apply_type_annotations.py
index 9c826cc43..20348170e 100644
--- a/libcst/codemod/visitors/_apply_type_annotations.py
+++ b/libcst/codemod/visitors/_apply_type_annotations.py
@@ -9,7 +9,6 @@
 
 import libcst as cst
 import libcst.matchers as m
-
 from libcst.codemod._context import CodemodContext
 from libcst.codemod._visitor import ContextAwareTransformer
 from libcst.codemod.visitors._add_imports import AddImportsVisitor
@@ -19,7 +18,6 @@
 from libcst.helpers import get_full_name_for_node
 from libcst.metadata import PositionProvider, QualifiedNameProvider
 
-
 NameOrAttribute = Union[cst.Name, cst.Attribute]
 NAME_OR_ATTRIBUTE = (cst.Name, cst.Attribute)
 # Union type for *args and **args
@@ -881,7 +879,7 @@ def _quote_future_annotations(self, annotation: cst.Annotation) -> cst.Annotatio
         if (
             isinstance(node, cst.Name)
             and (node.value in self.global_names)
-            and not (node.value in self.visited_classes)
+            and node.value not in self.visited_classes
         ):
             return annotation.with_changes(
                 annotation=cst.SimpleString(value=f'"{node.value}"')
diff --git a/libcst/matchers/__init__.py b/libcst/matchers/__init__.py
index 7e3761b82..ed40d70a8 100644
--- a/libcst/matchers/__init__.py
+++ b/libcst/matchers/__init__.py
@@ -12,7 +12,6 @@
 
 import libcst as cst
 from libcst.matchers._decorators import call_if_inside, call_if_not_inside, leave, visit
-
 from libcst.matchers._matcher_base import (
     AbstractBaseMatcherNodeMeta,
     AllOf,
diff --git a/libcst/matchers/_matcher_base.py b/libcst/matchers/_matcher_base.py
index 039694a5f..8792630f6 100644
--- a/libcst/matchers/_matcher_base.py
+++ b/libcst/matchers/_matcher_base.py
@@ -1017,7 +1017,7 @@ def _matches_zero_nodes(
         MatchIfTrue[libcst.CSTNode],
         _BaseMetadataMatcher,
         DoNotCareSentinel,
-    ]
+    ],
 ) -> bool:
     if isinstance(matcher, AtLeastN) and matcher.n == 0:
         return True
diff --git a/libcst/matchers/_return_types.py b/libcst/matchers/_return_types.py
index 9d20a23ad..e28e58006 100644
--- a/libcst/matchers/_return_types.py
+++ b/libcst/matchers/_return_types.py
@@ -71,7 +71,6 @@
     Yield,
 )
 from libcst._nodes.module import Module
-
 from libcst._nodes.op import (
     Add,
     AddAssign,
@@ -202,7 +201,6 @@
 )
 from libcst._removal_sentinel import RemovalSentinel
 
-
 TYPED_FUNCTION_RETURN_MAPPING: TypingDict[Type[CSTNode], object] = {
     Add: BaseBinaryOp,
     AddAssign: BaseAugOp,
diff --git a/libcst/metadata/accessor_provider.py b/libcst/metadata/accessor_provider.py
index 5d4f22e42..4563984bc 100644
--- a/libcst/metadata/accessor_provider.py
+++ b/libcst/metadata/accessor_provider.py
@@ -7,7 +7,6 @@
 import dataclasses
 
 import libcst as cst
-
 from libcst.metadata.base_provider import VisitorMetadataProvider
 
 
diff --git a/libcst/metadata/tests/test_accessor_provider.py b/libcst/metadata/tests/test_accessor_provider.py
index 6ccfad5ee..148ee9a73 100644
--- a/libcst/metadata/tests/test_accessor_provider.py
+++ b/libcst/metadata/tests/test_accessor_provider.py
@@ -4,7 +4,6 @@
 # LICENSE file in the root directory of this source tree.
 
 import dataclasses
-
 from textwrap import dedent
 
 import libcst as cst
diff --git a/libcst/tests/__main__.py b/libcst/tests/__main__.py
index 44e6bbe0a..a4bfb978a 100644
--- a/libcst/tests/__main__.py
+++ b/libcst/tests/__main__.py
@@ -7,7 +7,6 @@
 
 from libcst._parser.entrypoints import is_native
 
-
 if __name__ == "__main__":
     parser_type = "native" if is_native() else "pure"
     print(f"running tests with {parser_type!r} parser")
diff --git a/libcst/tests/test_add_slots.py b/libcst/tests/test_add_slots.py
index e354f60b6..5dd1d30d4 100644
--- a/libcst/tests/test_add_slots.py
+++ b/libcst/tests/test_add_slots.py
@@ -8,7 +8,6 @@
 from typing import ClassVar
 
 from libcst._add_slots import add_slots
-
 from libcst.testing.utils import UnitTest
 
 
diff --git a/pyproject.toml b/pyproject.toml
index dae305532..7a1d2e70e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -25,11 +25,10 @@ dependencies = [
 
 [project.optional-dependencies]
 dev = [
-    "black==23.9.1",
+    "black==23.9.1",  # required for testing formatting
     "coverage>=4.5.4",
     "build>=0.10.0",
     "fixit==2.0.0.post1",
-    "flake8==6.1.0",
     "Sphinx>=5.1.1",
     "hypothesis>=4.36.0",
     "hypothesmith>=0.0.4",
@@ -40,8 +39,7 @@ dev = [
     "pyre-check==0.9.18; platform_system != 'Windows'",
     "setuptools_scm>=6.0.1",
     "sphinx-rtd-theme>=0.4.3",
-    "ufmt==2.2.0",
-    "usort==1.0.7",
+    "ruff==0.1.6",
     "setuptools-rust>=1.5.2",
     "slotscheck>=0.7.1",
     "jinja2==3.1.2",
@@ -62,10 +60,9 @@ features = ["dev"]
 [tool.hatch.envs.default.scripts]
 docs = "sphinx-build -ab html docs/source docs/build"
 fixtures = ["python scripts/regenerate-fixtures.py", "git diff --exit-code"]
-format = "ufmt format libcst scripts"
+format = "ruff format ."
 lint = [
-    "flake8 libcst",
-    "ufmt check libcst scripts",
+    "ruff .",
     "python -m slotscheck libcst",
     "python scripts/check_copyright.py",
 ]
@@ -75,5 +72,34 @@ typecheck = ["pyre --version", "pyre check"]
 [tool.slotscheck]
 exclude-modules = '^libcst\.(testing|tests)'
 
-[tool.ufmt]
-excludes = ["native/", "stubs/"]
+[tool.ruff]
+exclude = [
+    ".pyre",
+    "__pycache__",
+    ".tox",
+    "native",
+    "stubs",
+]
+ignore = [
+    "E101",
+    "E401",
+    "E501",
+    "F811",
+    "W292",
+    "W293",
+    "W505",
+]
+extend-select = [
+    "C9",
+    "E",
+    "F",
+    "I",
+    "W",
+]
+
+[tool.ruff.isort]
+order-by-type = false
+combine-as-imports = true
+
+[tool.ruff.mccabe]
+max-complexity = 12