diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 2690c6bb8..927417f98 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -9,17 +9,15 @@ on:
 jobs:
   clang-format:
 
-    runs-on: ubuntu-20.04 # latest
+    runs-on: ubuntu-24.04 # latest
 
     steps:
     - name: Checkout Sources
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
 
     - name: clang-format lint
-      uses: DoozyX/clang-format-lint-action@v0.3.1
-      with:
-        # List of extensions to check
-        extensions: c,h
+      run: |
+        ./format-check.py
 
   autopep8:
     runs-on: ubuntu-20.04 # latest
diff --git a/format-check.py b/format-check.py
new file mode 100755
index 000000000..f9c17bdbe
--- /dev/null
+++ b/format-check.py
@@ -0,0 +1,46 @@
+#!/usr/bin/env python3
+import argparse
+import os
+from pathlib import Path
+import re
+from subprocess import list2cmdline, run
+from tempfile import NamedTemporaryFile
+
+CLANG_FORMAT_VERSION = '18.1.6'
+
+INCLUDE_REGEX = re.compile(r'^source/.*\.(c|h)$')
+EXCLUDE_REGEX = re.compile(r'^$')
+
+arg_parser = argparse.ArgumentParser(description="Check with clang-format")
+arg_parser.add_argument('-i', '--inplace-edit', action='store_true',
+                        help="Edit files inplace")
+args = arg_parser.parse_args()
+
+os.chdir(Path(__file__).parent)
+
+# create file containing list of all files to format
+filepaths_file = NamedTemporaryFile(delete=False)
+for dirpath, dirnames, filenames in os.walk('.'):
+    for filename in filenames:
+        # our regexes expect filepath to use forward slash
+        filepath = Path(dirpath, filename).as_posix()
+        if not INCLUDE_REGEX.match(filepath):
+            continue
+        if EXCLUDE_REGEX.match(filepath):
+            continue
+
+        filepaths_file.write(f"{filepath}\n".encode())
+filepaths_file.close()
+
+# use pipx to run clang-format from PyPI
+# this is a simple way to run the same clang-format version regardless of OS
+cmd = ['pipx', 'run', f'clang-format=={CLANG_FORMAT_VERSION}',
+       f'--files={filepaths_file.name}']
+if args.inplace_edit:
+    cmd += ['-i']
+else:
+    cmd += ['--Werror', '--dry-run']
+
+print(f"{Path.cwd()}$ {list2cmdline(cmd)}")
+if run(cmd).returncode:
+    exit(1)
diff --git a/format-check.sh b/format-check.sh
deleted file mode 100755
index fce95eabc..000000000
--- a/format-check.sh
+++ /dev/null
@@ -1,24 +0,0 @@
-#!/usr/bin/env bash
-
-if [[ -z $CLANG_FORMAT ]] ; then
-    CLANG_FORMAT=clang-format
-fi
-
-if NOT type $CLANG_FORMAT 2> /dev/null ; then
-    echo "No appropriate clang-format found."
-    exit 1
-fi
-
-FAIL=0
-SOURCE_FILES=`find source -type f \( -name '*.h' -o -name '*.c' \)`
-for i in $SOURCE_FILES
-do
-    $CLANG_FORMAT -output-replacements-xml $i | grep -c "<replacement " > /dev/null
-    if [ $? -ne 1 ]
-    then
-        echo "$i failed clang-format check."
-        FAIL=1
-    fi
-done
-
-exit $FAIL
diff --git a/guides/dev/README.md b/guides/dev/README.md
index 9fda4c7c0..39dc0189e 100644
--- a/guides/dev/README.md
+++ b/guides/dev/README.md
@@ -179,10 +179,11 @@ the code is formatted correctly.
 
 `autopep8` is used for python code. You installed this earlier via `requirements-dev.txt`.
 
-For C code `clang-format` is used (specifically version 9).
-To install this on Mac using homebrew, run:
+For C code `clang-format` is used. You need to install an exact version (see `CLANG_FORMAT_VERSION=...` line at the top of [format-check.py](../../format-check.py)) via [pipx](https://github.com/pypa/pipx). Doing this on MacOS looks like:
 ```sh
-(.venv) $ brew install llvm@9
+(.venv) $ brew install pipx
+(.venv) $ pipx ensurepath
+(.venv) $ pipx install clang-format==<CLANG_FORMAT_VERSION from format-check.py>
 ```
 
 Use helper scripts to automatically format your code (or configure your IDE to do it):
@@ -194,7 +195,7 @@ Use helper scripts to automatically format your code (or configure your IDE to d
 (.venv) $ python3 scripts/format-python.py
 
 # just format C files
-(.venv) $ python3 scripts/format-c.py
+(.venv) $ python3 format-check.py -i
 ```
 
 ## Using an IDE
diff --git a/scripts/format-all.py b/scripts/format-all.py
index a185d3669..ec816f028 100755
--- a/scripts/format-all.py
+++ b/scripts/format-all.py
@@ -3,5 +3,5 @@
 
 utils.chdir_project_root()
 
-utils.run('python3 scripts/format-c.py')
+utils.run('python3 format-check.py -i')
 utils.run('python3 scripts/format-python.py')
diff --git a/scripts/format-c.py b/scripts/format-c.py
deleted file mode 100755
index d52a1c8e6..000000000
--- a/scripts/format-c.py
+++ /dev/null
@@ -1,16 +0,0 @@
-#!/usr/bin/env python3
-import utils
-import glob
-
-FILE_PATTERNS = [
-    'source/**/*.h',
-    'source/**/*.c',
-]
-
-utils.chdir_project_root()
-
-files = []
-for pattern in FILE_PATTERNS:
-    files.extend(glob.glob(pattern, recursive=True))
-
-utils.run(['clang-format', '-i', *files])
diff --git a/source/module.c b/source/module.c
index 0648957e5..983054e79 100644
--- a/source/module.c
+++ b/source/module.c
@@ -364,7 +364,8 @@ PyObject *PyErr_AwsLastError(void) {
 }
 
 #define AWS_DEFINE_ERROR_INFO_CRT(CODE, STR)                                                                           \
-    [(CODE)-AWS_ERROR_ENUM_BEGIN_RANGE(AWS_CRT_PYTHON_PACKAGE_ID)] = AWS_DEFINE_ERROR_INFO(CODE, STR, "aws-crt-python")
+    [(CODE) - AWS_ERROR_ENUM_BEGIN_RANGE(AWS_CRT_PYTHON_PACKAGE_ID)] =                                                 \
+        AWS_DEFINE_ERROR_INFO(CODE, STR, "aws-crt-python")
 
 /* clang-format off */
 static struct aws_error_info s_errors[] = {
@@ -655,8 +656,7 @@ static void s_install_crash_handler(void) {
  * Definitions
  ******************************************************************************/
 
-#define AWS_PY_METHOD_DEF(NAME, FLAGS)                                                                                 \
-    { #NAME, aws_py_##NAME, (FLAGS), NULL }
+#define AWS_PY_METHOD_DEF(NAME, FLAGS) {#NAME, aws_py_##NAME, (FLAGS), NULL}
 
 static PyMethodDef s_module_methods[] = {
     /* Common */
diff --git a/source/mqtt5_client.c b/source/mqtt5_client.c
index bcedffaf4..243af6a0e 100644
--- a/source/mqtt5_client.c
+++ b/source/mqtt5_client.c
@@ -272,7 +272,9 @@ static void s_on_publish_received(const struct aws_mqtt5_packet_publish_view *pu
         /* i */ (int)(publish_packet->payload_format ? *publish_packet->payload_format : 0),
         /* O */ publish_packet->message_expiry_interval_seconds ? Py_True : Py_False,
         /* I */
-        (unsigned int)(publish_packet->message_expiry_interval_seconds ? *publish_packet->message_expiry_interval_seconds : 0),
+        (unsigned int)(publish_packet->message_expiry_interval_seconds
+                           ? *publish_packet->message_expiry_interval_seconds
+                           : 0),
         /* O */ publish_packet->topic_alias ? Py_True : Py_False,
         /* H */ (unsigned short)(publish_packet->topic_alias ? *publish_packet->topic_alias : 0),
         /* s */ publish_packet->response_topic ? publish_packet->response_topic->ptr : NULL,
@@ -544,7 +546,9 @@ static void s_lifecycle_event_disconnection(
         /* i */ (int)(disconnect ? disconnect->reason_code : 0),
         /* O */ (disconnect && disconnect->session_expiry_interval_seconds) ? Py_True : Py_False,
         /* I */
-        (unsigned int)((disconnect && disconnect->session_expiry_interval_seconds) ? *disconnect->session_expiry_interval_seconds : 0),
+        (unsigned int)((disconnect && disconnect->session_expiry_interval_seconds)
+                           ? *disconnect->session_expiry_interval_seconds
+                           : 0),
         /* s */ (disconnect && disconnect->reason_string) ? disconnect->reason_string->ptr : NULL,
         /* # */ (disconnect && disconnect->reason_string) ? disconnect->reason_string->len : 0,
         /* O */ user_property_count > 0 ? user_properties_list : Py_None,