diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index eb38f038..8d039f8b 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -58,6 +58,7 @@ repos:
       - types-jinja2
       - types-certifi
       - types-toml
+      - tomli
   - id: mypy
     name: mypy 3.7+ on bin/
     files: ^((bin|docs)/.*py|noxfile.py)$
@@ -69,7 +70,7 @@ repos:
       - types-pyyaml
       - types-click
       - types-requests
-      - types-toml
+      - tomli
 
 - repo: https://github.com/PyCQA/flake8
   rev: 4.0.1
diff --git a/bin/update_pythons.py b/bin/update_pythons.py
index 457d63a9..b1b2c95a 100755
--- a/bin/update_pythons.py
+++ b/bin/update_pythons.py
@@ -11,13 +11,13 @@ from typing import Any, Union
 import click
 import requests
 import rich
-import toml
+import tomli
 from packaging.specifiers import Specifier
 from packaging.version import Version
 from rich.logging import RichHandler
 from rich.syntax import Syntax
 
-from cibuildwheel.extra import InlineArrayDictEncoder
+from cibuildwheel.extra import dump_python_configurations
 from cibuildwheel.typing import Final, Literal, TypedDict
 
 log = logging.getLogger("cibw")
@@ -291,7 +291,8 @@ def update_pythons(force: bool, level: str) -> None:
     toml_file_path = RESOURCES_DIR / "build-platforms.toml"
 
     original_toml = toml_file_path.read_text()
-    configs = toml.loads(original_toml)
+    with toml_file_path.open("rb") as f:
+        configs = tomli.load(f)
 
     for config in configs["windows"]["python_configurations"]:
         all_versions.update_config(config)
@@ -299,7 +300,7 @@ def update_pythons(force: bool, level: str) -> None:
     for config in configs["macos"]["python_configurations"]:
         all_versions.update_config(config)
 
-    result_toml = toml.dumps(configs, encoder=InlineArrayDictEncoder())  # type: ignore
+    result_toml = dump_python_configurations(configs)
 
     rich.print()  # spacer
 
diff --git a/cibuildwheel/extra.py b/cibuildwheel/extra.py
index ea106130..60eecbad 100644
--- a/cibuildwheel/extra.py
+++ b/cibuildwheel/extra.py
@@ -2,22 +2,31 @@
 These are utilities for the `/bin` scripts, not for the `cibuildwheel` program.
 """
 
-from typing import Any, Dict
+from io import StringIO
+from typing import Dict, List
 
-import toml.encoder
-from packaging.version import Version
+from .typing import Protocol
+
+__all__ = ("Printable", "dump_python_configurations")
 
 
-class InlineArrayDictEncoder(toml.encoder.TomlEncoder):  # type: ignore
-    def __init__(self) -> None:
-        super().__init__()
-        self.dump_funcs[Version] = lambda v: f'"{v}"'
+class Printable(Protocol):
+    def __str__(self) -> str:
+        ...
 
-    def dump_sections(self, o: Dict[str, Any], sup: str) -> Any:
-        if not all(isinstance(a, list) for a in o.values()):
-            return super().dump_sections(o, sup)
-        val = ""
-        for k, v in o.items():
-            inner = ",\n  ".join(self.dump_inline_table(d_i).strip() for d_i in v)
-            val += f"{k} = [\n  {inner},\n]\n"
-        return val, self._dict()
+
+def dump_python_configurations(inp: Dict[str, Dict[str, List[Dict[str, Printable]]]]) -> str:
+    output = StringIO()
+    for header, values in inp.items():
+        output.write(f"[{header}]\n")
+        for inner_header, listing in values.items():
+            output.write(f"{inner_header} = [\n")
+            for item in listing:
+                output.write("  { ")
+                dict_contents = (f'{key} = "{value}"' for key, value in item.items())
+                output.write(", ".join(dict_contents))
+                output.write(" },\n")
+            output.write("]\n")
+        output.write("\n")
+    # Strip the final newline, to avoid two blank lines at the end.
+    return output.getvalue()[:-1]
diff --git a/cibuildwheel/options.py b/cibuildwheel/options.py
index 164cd409..6a1c19e3 100644
--- a/cibuildwheel/options.py
+++ b/cibuildwheel/options.py
@@ -5,7 +5,7 @@ from configparser import ConfigParser
 from pathlib import Path
 from typing import Any, Dict, List, Mapping, Optional, Set, Tuple, Union
 
-import toml
+import tomli
 from packaging.specifiers import SpecifierSet
 
 from .architecture import Architecture
@@ -143,7 +143,8 @@ class ConfigOptions:
         """
         Load a toml file, returns global and platform as separate dicts.
         """
-        config = toml.load(filename)
+        with filename.open("rb") as f:
+            config = tomli.load(f)
 
         global_options = config.get("tool", {}).get("cibuildwheel", {})
         platform_options = global_options.get(self.platform, {})
diff --git a/cibuildwheel/projectfiles.py b/cibuildwheel/projectfiles.py
index dd6efd07..6dda6582 100644
--- a/cibuildwheel/projectfiles.py
+++ b/cibuildwheel/projectfiles.py
@@ -4,7 +4,7 @@ from configparser import ConfigParser
 from pathlib import Path
 from typing import Any, Optional
 
-import toml
+import tomli
 
 if sys.version_info < (3, 8):
     Constant = ast.Str
@@ -56,7 +56,8 @@ def get_requires_python_str(package_dir: Path) -> Optional[str]:
 
     # Read in from pyproject.toml:project.requires-python
     try:
-        info = toml.load(package_dir / "pyproject.toml")
+        with (package_dir / "pyproject.toml").open("rb") as f1:
+            info = tomli.load(f1)
         return str(info["project"]["requires-python"])
     except (FileNotFoundError, KeyError, IndexError, TypeError):
         pass
@@ -70,8 +71,8 @@ def get_requires_python_str(package_dir: Path) -> Optional[str]:
         pass
 
     try:
-        with open(package_dir / "setup.py") as f:
-            return setup_py_python_requires(f.read())
+        with (package_dir / "setup.py").open() as f2:
+            return setup_py_python_requires(f2.read())
     except FileNotFoundError:
         pass
 
diff --git a/cibuildwheel/typing.py b/cibuildwheel/typing.py
index b8e91764..b9bd207b 100644
--- a/cibuildwheel/typing.py
+++ b/cibuildwheel/typing.py
@@ -4,9 +4,9 @@ import sys
 from typing import TYPE_CHECKING, NoReturn, Set, Union
 
 if sys.version_info < (3, 8):
-    from typing_extensions import Final, Literal, TypedDict
+    from typing_extensions import Final, Literal, Protocol, TypedDict
 else:
-    from typing import Final, Literal, TypedDict
+    from typing import Final, Literal, Protocol, TypedDict
 
 
 __all__ = (
@@ -18,6 +18,7 @@ __all__ = (
     "PopenBytes",
     "PathOrStr",
     "PlatformName",
+    "Protocol",
     "PLATFORMS",
     "assert_never",
 )
diff --git a/cibuildwheel/util.py b/cibuildwheel/util.py
index a5896ebd..016d559d 100644
--- a/cibuildwheel/util.py
+++ b/cibuildwheel/util.py
@@ -16,7 +16,7 @@ from typing import Dict, Iterator, List, NamedTuple, Optional, Set
 
 import bracex
 import certifi
-import toml
+import tomli
 from packaging.specifiers import SpecifierSet
 from packaging.version import Version
 
@@ -71,7 +71,8 @@ def get_build_verbosity_extra_flags(level: int) -> List[str]:
 
 def read_python_configs(config: PlatformName) -> List[Dict[str, str]]:
     input_file = resources_dir / "build-platforms.toml"
-    loaded_file = toml.load(input_file)
+    with input_file.open("rb") as f:
+        loaded_file = tomli.load(f)
     results: List[Dict[str, str]] = list(loaded_file[config]["python_configurations"])
     return results
 
diff --git a/pyproject.toml b/pyproject.toml
index 60ca9618..2789fd27 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -58,7 +58,6 @@ module = [
     "setuptools",
     "pytest", # ignored in pre-commit to speed up check
     "bashlex",
-    "toml.encoder", # encoder missing from stub package
     "bracex",
     "importlib_resources",
     "nox",
diff --git a/setup.cfg b/setup.cfg
index c14557d8..5cc57757 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -35,7 +35,7 @@ install_requires =
     bracex
     certifi
     packaging
-    toml
+    tomli
     typing_extensions;python_version < '3.8'
 python_requires = >=3.6
 include_package_data = True
diff --git a/unit_test/build_ids_test.py b/unit_test/build_ids_test.py
index 6aa100e3..927d110a 100644
--- a/unit_test/build_ids_test.py
+++ b/unit_test/build_ids_test.py
@@ -1,28 +1,32 @@
-import toml
+from typing import Dict, List
+
+import tomli
 from packaging.version import Version
 
-from cibuildwheel.extra import InlineArrayDictEncoder  # noqa: E402
+from cibuildwheel.extra import Printable, dump_python_configurations
 from cibuildwheel.util import resources_dir
 
 
 def test_compare_configs():
-    with open(resources_dir / "build-platforms.toml") as f:
-        txt = f.read()
+    with open(resources_dir / "build-platforms.toml") as f1:
+        txt = f1.read()
 
-    dict_txt = toml.loads(txt)
+    with open(resources_dir / "build-platforms.toml", "rb") as f2:
+        dict_txt = tomli.load(f2)
 
-    new_txt = toml.dumps(dict_txt, encoder=InlineArrayDictEncoder())  # type: ignore
+    new_txt = dump_python_configurations(dict_txt)
     print(new_txt)
 
     assert new_txt == txt
 
 
 def test_dump_with_Version():
-    example = {
+    # MyPy doesn't understand deeply nested dicts correctly
+    example: Dict[str, Dict[str, List[Dict[str, Printable]]]] = {
         "windows": {
             "python_configurations": [
                 {"identifier": "cp27-win32", "version": Version("2.7.18"), "arch": "32"},
-                {"identifier": "cp27-win_amd64", "version": Version("2.7.18"), "arch": "64"},
+                {"identifier": "cp27-win_amd64", "version": "2.7.18", "arch": "64"},
             ]
         }
     }
@@ -35,6 +39,6 @@ python_configurations = [
 ]
 """
 
-    output = toml.dumps(example, encoder=InlineArrayDictEncoder())  # type: ignore
+    output = dump_python_configurations(example)
     print(output)
     assert output == result