diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 91bc539..609feec 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.7", "3.8", "3.9", "3.10"]
+        python-version: ["3.8", "3.9", "3.10"]
       # Ensure that all flavours are run to completion even if an other flavor failed
       fail-fast: false
 
diff --git a/Makefile b/Makefile
index a7eaf0a..7690e58 100644
--- a/Makefile
+++ b/Makefile
@@ -117,15 +117,15 @@ flake8: venv
 	@printf "${TERM_BRIGHT}FLAKE8 ${ALL_SRCS}\n${TERM_NONE}"
 	${Q} ${CURDIR}/venv/bin/flake8 --select=F,C90 $(ALL_SRCS)
 
-.PHONY: black
-black: venv
-	@printf "${TERM_BRIGHT}BLACK ${ALL_SRCS}\n${TERM_NONE}"
-	${Q} ${CURDIR}/venv/bin/black --check --diff $(ALL_SRCS) || { echo "Formatting errors found, try running 'make format'."; exit 1; }
+.PHONY: ruff
+ruff: venv
+	@printf "${TERM_BRIGHT}RUFF check ${ALL_SRCS}\n${TERM_NONE}"
+	${Q} ${CURDIR}/venv/bin/ruff check --diff $(ALL_SRCS) || { echo "Formatting errors found, try running 'make format'."; exit 1; }
 
-.PHONY: format_black
-format_black: venv
+.PHONY: format_ruff
+format_ruff: venv
 	@printf "${TERM_BRIGHT}FORMAT BLACK ${ALL_SRCS}\n${TERM_NONE}"
-	${Q} ${CURDIR}/venv/bin/black $(ALL_SRCS)
+	${Q} ${CURDIR}/venv/bin/ruff format $(ALL_SRCS)
 
 .PHONY: tests
 tests: \
@@ -134,12 +134,12 @@ tests: \
 	pytest_tests \
 	mypy \
 	flake8 \
-	black \
+	ruff \
 	check-copyright
 
 .PHONY: format
 format: \
-	format_black
+	format_ruff
 	@true
 ##
 ## Coverage
diff --git a/requirements-dev.txt b/requirements-dev.txt
index f4c633e..b72c75d 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,4 +1,4 @@
-black
+ruff
 coverage
 coveralls
 flake8
diff --git a/testslide/bdd/dsl.py b/testslide/bdd/dsl.py
index e66eedf..c4a5b8b 100644
--- a/testslide/bdd/dsl.py
+++ b/testslide/bdd/dsl.py
@@ -201,7 +201,7 @@ def nest_context(self, name: str, *args: Any, **kwargs: Any) -> None:
             raise TypeError('Shared context "{}" does not exist'.format(name))
         self._create_context(
             name,
-            self.current_context.all_shared_contexts[name],
+            self.current_context.all_shared_contexts[name],  # type: ignore
             *args,
             **kwargs,  # type: ignore
         )
diff --git a/testslide/bdd/lib.py b/testslide/bdd/lib.py
index de6d36f..31bcaa9 100644
--- a/testslide/bdd/lib.py
+++ b/testslide/bdd/lib.py
@@ -429,7 +429,7 @@ def addError(  # type:ignore
     #  inconsistently.
     def addFailure(  # type:ignore
         self,
-        test: "TestCase",
+        test: "TestCase",  # type: ignore
         err: Tuple[
             Type[BaseException],
             BaseException,
@@ -456,9 +456,9 @@ def addUnexpectedSuccess(self, test: "TestCase") -> None:  # type: ignore
     # pyre-ignore
     def addSubTest(
         self,
-        test: "TestCase",
-        subtest: "TestCase",
-        err: Tuple[
+        test: "TestCase",  # type: ignore
+        subtest: "TestCase",  # type: ignore
+        err: Tuple[  # type: ignore
             Optional[Type[BaseException]],
             Optional[BaseException],
             Optional[types.TracebackType],
@@ -532,7 +532,7 @@ class Context:
     def __init__(
         self,
         name: str,
-        parent_context: Optional["Context"] = None,
+        parent_context: Optional["Context"] = None,  # type: ignore
         shared: bool = False,
         skip: bool = False,
         focus: bool = False,
diff --git a/testslide/cli.pyi b/testslide/cli.pyi
index 89fc06a..328b050 100644
--- a/testslide/cli.pyi
+++ b/testslide/cli.pyi
@@ -1,6 +1,6 @@
 # pyre-unsafe
 from testslide.executor.cli import *
-from testslide.executor.import_profiler import ImportedModule, ImportProfiler
+from testslide.executor.import_profiler import ImportedModule, ImportProfiler  # noqa
 
 # pyre-fixme[21]: Could not find name `AggregatedExceptions` in
 #  `testslide.executor.lib`.
diff --git a/testslide/core/mock_callable.py b/testslide/core/mock_callable.py
index 868c2b4..722652e 100644
--- a/testslide/core/mock_callable.py
+++ b/testslide/core/mock_callable.py
@@ -170,7 +170,7 @@ def _is_coroutine(obj: Any) -> bool:
         return inspect.iscoroutine(obj) or isinstance(
             obj,
             # pyre-ignore
-            asyncio.coroutines.CoroWrapper,
+            asyncio.coroutines.CoroWrapper,  # type: ignore
         )
     else:
         return inspect.iscoroutine(obj)
@@ -1014,7 +1014,7 @@ def to_raise(
                 _RaiseRunner(
                     self._original_target,
                     self._method,
-                    self._original_callable,
+                    self._original_callable,  # type: ignore
                     ex,  # type: ignore
                 )
             )
@@ -1023,7 +1023,7 @@ def to_raise(
                 _RaiseRunner(
                     self._original_target,
                     self._method,
-                    self._original_callable,
+                    self._original_callable,  # type: ignore
                     ex(),  # type: ignore
                 )
             )
@@ -1246,7 +1246,7 @@ def with_implementation(self, func: Callable) -> "_MockAsyncCallableDSL":
             _AsyncImplementationRunner(
                 self._original_target,
                 self._method,
-                self._original_callable,
+                self._original_callable,  # type: ignore
                 func,  # type: ignore
             )
         )
diff --git a/testslide/core/mock_constructor.py b/testslide/core/mock_constructor.py
index cebd472..19813c4 100644
--- a/testslide/core/mock_constructor.py
+++ b/testslide/core/mock_constructor.py
@@ -341,7 +341,7 @@ def mock_constructor(
 
     if target_class_id in _mocked_target_classes:
         original_class, mocked_class = _mocked_target_classes[target_class_id]
-        if not getattr(target, class_name) is mocked_class:
+        if getattr(target, class_name) is not mocked_class:
             raise AssertionError(
                 "The class {} at {} was changed after mock_constructor() mocked "
                 "it!".format(class_name, target)
diff --git a/testslide/executor/cli.py b/testslide/executor/cli.py
index e0f8092..fc64eee 100644
--- a/testslide/executor/cli.py
+++ b/testslide/executor/cli.py
@@ -158,7 +158,7 @@ def example_code(self: Any) -> None:
             "{}.{}".format(
                 test_case.__module__,
                 # pyre-ignore
-                test_case.__name__,
+                test_case.__name__,  # type: ignore
             )
         )(get_context_code(test_case))
 
diff --git a/testslide/executor/runner.py b/testslide/executor/runner.py
index 3781b9b..cfe7329 100644
--- a/testslide/executor/runner.py
+++ b/testslide/executor/runner.py
@@ -532,7 +532,7 @@ def finish(self, not_executed_examples: List[Example]) -> None:
                 print("")
                 self.print_failed_example(
                     number + 1,
-                    result["example"],
+                    result["example"],  # type: ignore
                     result["exception"],  # type: ignore
                 )
         print("")
diff --git a/testslide/lib.pyi b/testslide/lib.pyi
index 948ad4d..7a7a122 100644
--- a/testslide/lib.pyi
+++ b/testslide/lib.pyi
@@ -1,9 +1,9 @@
 # pyre-unsafe
 from testslide.core.lib import (
-    _extract_NonCallableMock_template,
-    CoroutineValueError,
+    _extract_NonCallableMock_template,  # noqa
+    CoroutineValueError,  # noqa
     TypeCheckError,
-    WrappedMock,
+    WrappedMock,  # noqa
 )
 
 TypeCheckError = TypeCheckError