diff --git a/README.rst b/README.rst
index eb6c615..a035f33 100644
--- a/README.rst
+++ b/README.rst
@@ -26,7 +26,7 @@ Usage—you are responsible for ensuring build requirements are available:
     from pep517.wrappers import Pep517HookCaller
 
     src = 'path/to/source'  # Folder containing 'pyproject.toml'
-    with open(os.path.join(src, 'pyproject.toml')) as f:
+    with open(os.path.join(src, 'pyproject.toml'), 'rb') as f:
         build_sys = tomli.load(f)['build-system']
 
     print(build_sys['requires'])  # List of static requirements
diff --git a/dev-requirements.txt b/dev-requirements.txt
index 34c422c..1384c9c 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -1,6 +1,6 @@
 pytest
 pytest-flake8
-flake8 < 4  # https://github.com/tholo/pytest-flake8/issues/81
+flake8
 testpath
 tomli
 setuptools>=30
diff --git a/pep517/_compat.py b/pep517/_compat.py
new file mode 100644
index 0000000..c06d7fe
--- /dev/null
+++ b/pep517/_compat.py
@@ -0,0 +1,8 @@
+__all__ = ("tomllib",)
+
+import sys
+
+if sys.version_info >= (3, 11):
+    import tomllib
+else:
+    import tomli as tomllib
diff --git a/pep517/build.py b/pep517/build.py
index ad1c253..b30909c 100644
--- a/pep517/build.py
+++ b/pep517/build.py
@@ -6,8 +6,7 @@
 import shutil
 import tempfile
 
-import tomli
-
+from ._compat import tomllib
 from .envbuild import BuildEnvironment
 from .wrappers import Pep517HookCaller
 
@@ -32,7 +31,7 @@ def load_system(source_dir):
     """
     pyproject = os.path.join(source_dir, 'pyproject.toml')
     with open(pyproject, 'rb') as f:
-        pyproject_data = tomli.load(f)
+        pyproject_data = tomllib.load(f)
     return pyproject_data['build-system']
 
 
diff --git a/pep517/check.py b/pep517/check.py
index a5f9305..b79f627 100644
--- a/pep517/check.py
+++ b/pep517/check.py
@@ -12,8 +12,7 @@
 from subprocess import CalledProcessError
 from tempfile import mkdtemp
 
-import tomli
-
+from ._compat import tomllib
 from .colorlog import enable_colourful_output
 from .envbuild import BuildEnvironment
 from .wrappers import Pep517HookCaller
@@ -144,14 +143,14 @@ def check(source_dir):
 
     try:
         with open(pyproject, 'rb') as f:
-            pyproject_data = tomli.load(f)
+            pyproject_data = tomllib.load(f)
         # Ensure the mandatory data can be loaded
         buildsys = pyproject_data['build-system']
         requires = buildsys['requires']
         backend = buildsys['build-backend']
         backend_path = buildsys.get('backend-path')
         log.info('Loaded pyproject.toml')
-    except (tomli.TOMLDecodeError, KeyError):
+    except (tomllib.TOMLDecodeError, KeyError):
         log.error("Invalid pyproject.toml", exc_info=True)
         return False
 
diff --git a/pep517/envbuild.py b/pep517/envbuild.py
index 8437e1b..c0415c4 100644
--- a/pep517/envbuild.py
+++ b/pep517/envbuild.py
@@ -9,8 +9,7 @@
 from sysconfig import get_paths
 from tempfile import mkdtemp
 
-import tomli
-
+from ._compat import tomllib
 from .wrappers import LoggerWrapper, Pep517HookCaller
 
 log = logging.getLogger(__name__)
@@ -21,7 +20,7 @@ def _load_pyproject(source_dir):
             os.path.join(source_dir, 'pyproject.toml'),
             'rb',
             ) as f:
-        pyproject_data = tomli.load(f)
+        pyproject_data = tomllib.load(f)
     buildsys = pyproject_data['build-system']
     return (
         buildsys['requires'],
diff --git a/pyproject.toml b/pyproject.toml
index bd3650f..f24e689 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -9,7 +9,7 @@ author-email = "thomas@kluyver.me.uk"
 home-page = "https://github.com/pypa/pep517"
 description-file = "README.rst"
 requires = [
-    "tomli >=1.1.0",
+    "tomli >=1.1.0;python_version<'3.11'",
     "importlib_metadata;python_version<'3.8'",
     "zipp;python_version<'3.8'",
 ]