diff --git a/src/async_wrap.cc b/src/async_wrap.cc
index 4c8647604ae1df..22d5d91eb096f9 100644
--- a/src/async_wrap.cc
+++ b/src/async_wrap.cc
@@ -19,6 +19,7 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
+#include "async_wrap.h"  // NOLINT(build/include_inline)
 #include "async_wrap-inl.h"
 #include "env-inl.h"
 #include "node_errors.h"
diff --git a/src/debug_utils.cc b/src/debug_utils.cc
index f1024183cdaedf..bff2f9ae915c8e 100644
--- a/src/debug_utils.cc
+++ b/src/debug_utils.cc
@@ -22,11 +22,6 @@
 #include <cstdio>
 #endif
 
-#else  // __POSIX__
-
-#include <windows.h>
-#include <dbghelp.h>
-
 #endif  // __POSIX__
 
 #if defined(__linux__) || defined(__sun) || defined(__FreeBSD__)
diff --git a/src/env.cc b/src/env.cc
index 767cde7ae79241..095715380323ea 100644
--- a/src/env.cc
+++ b/src/env.cc
@@ -1,3 +1,5 @@
+#include "env.h"
+
 #include "async_wrap.h"
 #include "node_buffer.h"
 #include "node_context_data.h"
@@ -14,9 +16,9 @@
 #include "tracing/traced_value.h"
 #include "v8-profiler.h"
 
-#include <cstdio>
 #include <algorithm>
 #include <atomic>
+#include <cstdio>
 
 namespace node {
 
diff --git a/src/inspector/main_thread_interface.cc b/src/inspector/main_thread_interface.cc
index 14f90fbd9d3a6c..af123d9ac5b549 100644
--- a/src/inspector/main_thread_interface.cc
+++ b/src/inspector/main_thread_interface.cc
@@ -2,10 +2,11 @@
 
 #include "node_mutex.h"
 #include "v8-inspector.h"
+#include "util-inl.h"
 
-#include <functional>
 #include <unicode/unistr.h>
-#include "util-inl.h"
+
+#include <functional>
 
 namespace node {
 namespace inspector {
diff --git a/src/inspector_agent.cc b/src/inspector_agent.cc
index 2376ae50044f0e..7b4dec90fc9548 100644
--- a/src/inspector_agent.cc
+++ b/src/inspector_agent.cc
@@ -16,16 +16,16 @@
 
 #include "libplatform/libplatform.h"
 
+#ifdef __POSIX__
+#include <pthread.h>
+#include <climits>  // PTHREAD_STACK_MIN
+#endif  // __POSIX__
+
 #include <cstring>
 #include <sstream>
 #include <unordered_map>
 #include <vector>
 
-#ifdef __POSIX__
-#include <climits>  // PTHREAD_STACK_MIN
-#include <pthread.h>
-#endif  // __POSIX__
-
 namespace node {
 namespace inspector {
 namespace {
diff --git a/src/inspector_agent.h b/src/inspector_agent.h
index b8b03b2edc3388..aa89fbba6bc099 100644
--- a/src/inspector_agent.h
+++ b/src/inspector_agent.h
@@ -1,12 +1,7 @@
-#ifndef SRC_INSPECTOR_AGENT_H_
-#define SRC_INSPECTOR_AGENT_H_
+#pragma once
 
 #if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
 
-#include <memory>
-
-#include <cstddef>
-
 #if !HAVE_INSPECTOR
 #error("This header can only be used when inspector is enabled")
 #endif
@@ -15,6 +10,9 @@
 #include "node_persistent.h"
 #include "v8.h"
 
+#include <cstddef>
+#include <memory>
+
 namespace v8_inspector {
 class StringView;
 }  // namespace v8_inspector
@@ -143,5 +141,3 @@ class Agent {
 }  // namespace node
 
 #endif  // defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
-
-#endif  // SRC_INSPECTOR_AGENT_H_
diff --git a/src/inspector_io.h b/src/inspector_io.h
index e4b4ee44f81d8c..0dfb08f470345e 100644
--- a/src/inspector_io.h
+++ b/src/inspector_io.h
@@ -1,18 +1,18 @@
-#ifndef SRC_INSPECTOR_IO_H_
-#define SRC_INSPECTOR_IO_H_
+#pragma once
 
 #if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
 
+#if !HAVE_INSPECTOR
+#error("This header can only be used when inspector is enabled")
+#endif
+
 #include "inspector_socket_server.h"
 #include "node_mutex.h"
+
 #include "uv.h"
 
-#include <memory>
 #include <cstddef>
-
-#if !HAVE_INSPECTOR
-#error("This header can only be used when inspector is enabled")
-#endif
+#include <memory>
 
 
 namespace v8_inspector {
@@ -93,5 +93,3 @@ class InspectorIo {
 }  // namespace node
 
 #endif  // defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
-
-#endif  // SRC_INSPECTOR_IO_H_
diff --git a/src/inspector_socket.cc b/src/inspector_socket.cc
index e341d3c2557a61..a95f768e16553a 100644
--- a/src/inspector_socket.cc
+++ b/src/inspector_socket.cc
@@ -12,8 +12,8 @@
 
 #include "openssl/sha.h"  // Sha-1 hash
 
-#include <map>
 #include <cstring>
+#include <map>
 
 #define ACCEPT_KEY_LENGTH base64_encoded_size(20)
 
diff --git a/src/large_pages/node_large_page.cc b/src/large_pages/node_large_page.cc
index 4b860d9ccb47ca..ad599a1a91bfdc 100644
--- a/src/large_pages/node_large_page.cc
+++ b/src/large_pages/node_large_page.cc
@@ -20,8 +20,8 @@
 //
 // SPDX-License-Identifier: MIT
 
-#include <errno.h>
-#include <fcntl.h>  // _O_RDWR
+#include <errno.h>   // NOLINT(build/include)
+#include <fcntl.h>   // _O_RDWR
 #include <limits.h>  // PATH_MAX
 #include <locale.h>
 #include <signal.h>
@@ -31,11 +31,12 @@
 #include <string.h>
 #include <sys/types.h>
 #include <sys/mman.h>
+#include <unistd.h>  // readlink
+
 #include <string>
 #include <fstream>
 #include <iostream>
 #include <sstream>
-#include <unistd.h>  // readlink
 
 // The functions in this file map the text segment of node into 2M pages.
 // The algorithm is simple
diff --git a/src/memory_tracker.h b/src/memory_tracker.h
index 4125f9585f1d74..c5d9b2106f0826 100644
--- a/src/memory_tracker.h
+++ b/src/memory_tracker.h
@@ -1,16 +1,17 @@
-#ifndef SRC_MEMORY_TRACKER_H_
-#define SRC_MEMORY_TRACKER_H_
+#pragma once
 
 #if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
 
-#include <unordered_map>
+#include "aliased_buffer.h"
+#include "v8-profiler.h"
+
+#include <uv.h>
+
+#include <limits>
 #include <queue>
 #include <stack>
 #include <string>
-#include <limits>
-#include <uv.h>
-#include "aliased_buffer.h"
-#include "v8-profiler.h"
+#include <unordered_map>
 
 namespace node {
 
@@ -253,5 +254,3 @@ class MemoryTracker {
 }  // namespace node
 
 #endif  // defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
-
-#endif  // SRC_MEMORY_TRACKER_H_
diff --git a/src/module_wrap.cc b/src/module_wrap.cc
index 3d55d12cc3874a..d311f7cacaee1e 100644
--- a/src/module_wrap.cc
+++ b/src/module_wrap.cc
@@ -1,6 +1,3 @@
-#include <algorithm>
-#include <climits>  // PATH_MAX
-#include <sys/stat.h>  // S_IFDIR
 #include "module_wrap.h"
 
 #include "env.h"
@@ -10,6 +7,11 @@
 #include "node_contextify.h"
 #include "node_watchdog.h"
 
+#include <sys/stat.h>  // S_IFDIR
+
+#include <algorithm>
+#include <climits>  // PATH_MAX
+
 namespace node {
 namespace loader {
 
diff --git a/src/node.cc b/src/node.cc
index f7ce82b3258ce7..e5d671c58b489d 100644
--- a/src/node.cc
+++ b/src/node.cc
@@ -19,6 +19,10 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
+#include "node.h"
+
+// ========== local headers ==========
+
 #include "debug_utils.h"
 #include "node_binding.h"
 #include "node_buffer.h"
@@ -72,25 +76,19 @@
 #include "large_pages/node_large_page.h"
 #endif
 
-#include <cerrno>
+#ifdef NODE_REPORT
+#include "node_report.h"
+#endif
+
+// ========== global C headers ==========
+
 #include <fcntl.h>  // _O_RDWR
-#include <climits>  // PATH_MAX
-#include <csignal>
-#include <cstdio>
-#include <cstdlib>
-#include <cstring>
 #include <sys/types.h>
 
-#include <string>
-#include <vector>
-
 #if defined(NODE_HAVE_I18N_SUPPORT)
 #include <unicode/uvernum.h>
 #endif
 
-#ifdef NODE_REPORT
-#include "node_report.h"
-#endif
 
 #if defined(LEAK_SANITIZER)
 #include <sanitizer/lsan_interface.h>
@@ -106,6 +104,18 @@
 #include <unistd.h>        // STDIN_FILENO, STDERR_FILENO
 #endif
 
+// ========== global C++ headers ==========
+
+#include <cerrno>
+#include <climits>  // PATH_MAX
+#include <csignal>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+
+#include <string>
+#include <vector>
+
 namespace node {
 
 using options_parser::kAllowedInEnvironment;
diff --git a/src/node_constants.cc b/src/node_constants.cc
index e4eae1727cb62e..be27de4ed64430 100644
--- a/src/node_constants.cc
+++ b/src/node_constants.cc
@@ -24,28 +24,31 @@
 
 #include "zlib.h"
 
-#include <cerrno>
 #if !defined(_MSC_VER)
 #include <unistd.h>
 #endif
+
 #include <fcntl.h>
-#include <csignal>
 #include <sys/types.h>
 #include <sys/stat.h>
-#include <limits>
+
 
 #if HAVE_OPENSSL
-# include <openssl/ec.h>
-# include <openssl/ssl.h>
-# ifndef OPENSSL_NO_ENGINE
-#  include <openssl/engine.h>
-# endif  // !OPENSSL_NO_ENGINE
-#endif
+#include <openssl/ec.h>
+#include <openssl/ssl.h>
+#ifndef OPENSSL_NO_ENGINE
+#include <openssl/engine.h>
+#endif  // !OPENSSL_NO_ENGINE
+#endif  // HAVE_OPENSSL
 
 #if defined(__POSIX__)
 #include <dlfcn.h>
 #endif
 
+#include <cerrno>
+#include <csignal>
+#include <limits>
+
 namespace node {
 
 using v8::Local;
diff --git a/src/node_contextify.cc b/src/node_contextify.cc
index 0ba2b1a90cb93b..b9962f091d9e40 100644
--- a/src/node_contextify.cc
+++ b/src/node_contextify.cc
@@ -19,11 +19,11 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-#include "node_errors.h"
+#include "node_contextify.h"
+
 #include "node_internals.h"
 #include "node_watchdog.h"
 #include "base_object-inl.h"
-#include "node_contextify.h"
 #include "node_context_data.h"
 #include "node_errors.h"
 #include "module_wrap.h"
diff --git a/src/node_crypto_clienthello.cc b/src/node_crypto_clienthello.cc
index b0375755774318..268d4773570f8b 100644
--- a/src/node_crypto_clienthello.cc
+++ b/src/node_crypto_clienthello.cc
@@ -19,6 +19,7 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
+#include "node_crypto_clienthello.h"  // NOLINT(build/include_inline)
 #include "node_crypto_clienthello-inl.h"
 
 namespace node {
diff --git a/src/node_http_parser_impl.h b/src/node_http_parser_impl.h
index 7a51a3140d212e..a154af5cfbaf4e 100644
--- a/src/node_http_parser_impl.h
+++ b/src/node_http_parser_impl.h
@@ -22,8 +22,7 @@
 // This file is included from 2 files, node_http_parser_traditional.cc
 // and node_http_parser_llhttp.cc.
 
-#ifndef SRC_NODE_HTTP_PARSER_IMPL_H_
-#define SRC_NODE_HTTP_PARSER_IMPL_H_
+#pragma once
 
 #include "node.h"
 #include "node_buffer.h"
@@ -32,13 +31,13 @@
 #include "async_wrap-inl.h"
 #include "env-inl.h"
 #include "stream_base-inl.h"
-#include "util-inl.h"
 #include "v8.h"
 
+#include "http_parser_adaptor.h"
+
 #include <cstdlib>  // free()
 #include <cstring>  // strdup(), strchr()
 
-#include "http_parser_adaptor.h"
 
 // This is a binding to http_parser (https://github.com/nodejs/http-parser)
 // The goal is to decouple sockets from parsing for more javascript-level
@@ -978,5 +977,3 @@ void InitializeHttpParser(Local<Object> target,
 
 }  // anonymous namespace
 }  // namespace node
-
-#endif  // SRC_NODE_HTTP_PARSER_IMPL_H_
diff --git a/src/node_messaging.cc b/src/node_messaging.cc
index 4fda880c1c3a0e..e6e7f743de27ad 100644
--- a/src/node_messaging.cc
+++ b/src/node_messaging.cc
@@ -1,11 +1,10 @@
 #include "node_messaging.h"
+
 #include "async_wrap-inl.h"
-#include "async_wrap.h"
 #include "debug_utils.h"
 #include "node_buffer.h"
 #include "node_errors.h"
 #include "node_process.h"
-#include "util-inl.h"
 #include "util.h"
 
 using v8::Array;
diff --git a/src/node_options.cc b/src/node_options.cc
index 4ae7ea16941803..ebd4baf2b7c6a8 100644
--- a/src/node_options.cc
+++ b/src/node_options.cc
@@ -1,7 +1,10 @@
-#include <cerrno>
+#include "node_options.h"  // NOLINT(build/include_inline)
+#include "node_options-inl.h"
+
 #include "env-inl.h"
 #include "node_binding.h"
-#include "node_options-inl.h"
+
+#include <cstdlib>  // strtoul, errno
 
 using v8::Boolean;
 using v8::Context;
diff --git a/src/node_os.cc b/src/node_os.cc
index c79fc00b2358cb..57972d6b5aa37d 100644
--- a/src/node_os.cc
+++ b/src/node_os.cc
@@ -23,20 +23,20 @@
 #include "string_bytes.h"
 #include "util.h"
 
-#include <array>
-#include <cerrno>
-#include <cstring>
-
 #ifdef __MINGW32__
 # include <io.h>
 #endif  // __MINGW32__
 
 #ifdef __POSIX__
-# include <climits>         // PATH_MAX on Solaris.
 # include <unistd.h>        // gethostname, sysconf
 # include <sys/utsname.h>
+# include <climits>         // PATH_MAX on Solaris.
 #endif  // __POSIX__
 
+#include <array>
+#include <cerrno>
+#include <cstring>
+
 namespace node {
 namespace os {
 
diff --git a/src/node_process_methods.cc b/src/node_process_methods.cc
index b46735bc791dd4..3cf2670a88bac2 100644
--- a/src/node_process_methods.cc
+++ b/src/node_process_methods.cc
@@ -1,5 +1,4 @@
 #include "base_object-inl.h"
-#include "base_object.h"
 #include "env-inl.h"
 #include "node.h"
 #include "node_errors.h"
diff --git a/src/node_report.cc b/src/node_report.cc
index 5cbfd27d7694c4..a319f51fdb1a9e 100644
--- a/src/node_report.cc
+++ b/src/node_report.cc
@@ -8,8 +8,11 @@
 #include "node_metadata.h"
 #include "zlib.h"
 
-#include <atomic>
-#include <fstream>
+#ifdef __APPLE__
+#include <mach-o/dyld.h>
+#endif
+
+#include <fcntl.h>
 
 #ifdef _WIN32
 #include <Lm.h>
@@ -18,31 +21,19 @@
 #include <process.h>
 #include <psapi.h>
 #include <tchar.h>
-#include <cwctype>
-#else
+#else  // !_WIN32
 #include <sys/resource.h>
-// Get the standard printf format macros for C99 stdint types.
-#ifndef __STDC_FORMAT_MACROS
-#define __STDC_FORMAT_MACROS
-#endif
 #include <cxxabi.h>
 #include <dlfcn.h>
-#include <cinttypes>
 #endif
 
-#include <fcntl.h>
 #include <cstring>
 #include <ctime>
+#include <cwctype>
+#include <atomic>
+#include <fstream>
 #include <iomanip>
 
-#ifndef _MSC_VER
-#include <strings.h>
-#endif
-
-#ifdef __APPLE__
-#include <mach-o/dyld.h>
-#endif
-
 #ifndef _WIN32
 extern char** environ;
 #endif
diff --git a/src/node_report.h b/src/node_report.h
index 18135f5666c68a..9ba45053996827 100644
--- a/src/node_report.h
+++ b/src/node_report.h
@@ -1,26 +1,10 @@
-#ifndef SRC_NODE_REPORT_H_
-#define SRC_NODE_REPORT_H_
+#pragma once
 
-#include <node.h>
-#include <node_buffer.h>
-#include <uv.h>
-#include <algorithm>
-#include <climits>
-#include <cstdlib>
-#include <cstring>
-#include <queue>
-#include <string>
-#include <utility>
-#include <vector>
+#include "node.h"
+#include "node_buffer.h"
+#include "uv.h"
 #include "v8.h"
 
-#include <cstdio>
-#include <cstdlib>
-#include <iomanip>
-#include <iostream>
-#include <sstream>
-#include <limits>
-
 #ifdef _WIN32
 #include <time.h>
 #else
@@ -29,6 +13,20 @@
 #include <unistd.h>
 #endif
 
+#include <climits>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <iomanip>
+#include <iostream>
+#include <sstream>
+#include <limits>
+#include <algorithm>
+#include <queue>
+#include <string>
+#include <utility>
+#include <vector>
+
 namespace report {
 
 #ifdef _WIN32
@@ -185,5 +183,3 @@ class JSONWriter {
 };
 
 }  // namespace report
-
-#endif  // SRC_NODE_REPORT_H_
diff --git a/src/node_report_module.cc b/src/node_report_module.cc
index 94894b0f5e5f9c..3317077e8b9814 100644
--- a/src/node_report_module.cc
+++ b/src/node_report_module.cc
@@ -5,12 +5,10 @@
 #include "node_report.h"
 #include "util.h"
 
-#include "env-inl.h"
 #include "handle_wrap.h"
 #include "node_buffer.h"
 #include "stream_base-inl.h"
 #include "stream_wrap.h"
-#include "util-inl.h"
 
 #include <v8.h>
 #include <atomic>
diff --git a/src/node_url.cc b/src/node_url.cc
index 2070b713ac3d60..5e241b76f12c7c 100644
--- a/src/node_url.cc
+++ b/src/node_url.cc
@@ -4,10 +4,10 @@
 #include "node_i18n.h"
 #include "util.h"
 
+#include <cmath>
+#include <cstdio>
 #include <string>
 #include <vector>
-#include <cstdio>
-#include <cmath>
 
 namespace node {
 
diff --git a/src/node_win32_etw_provider.cc b/src/node_win32_etw_provider.cc
index 8a854767d6aed8..5c45a8e2b8c82a 100644
--- a/src/node_win32_etw_provider.cc
+++ b/src/node_win32_etw_provider.cc
@@ -19,10 +19,11 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-#include "node_win32_etw_provider.h"
-#include "node_etw_provider.h"
+#include "node_win32_etw_provider.h"  // NOLINT(build/include_inline)
 #include "node_win32_etw_provider-inl.h"
 
+#include "node_etw_provider.h"
+
 namespace node {
 
 using v8::JitCodeEvent;
diff --git a/src/node_worker.cc b/src/node_worker.cc
index ca4d03f6d205e3..b79ba29e3feba1 100644
--- a/src/node_worker.cc
+++ b/src/node_worker.cc
@@ -4,8 +4,6 @@
 #include "node_buffer.h"
 #include "node_perf.h"
 #include "util.h"
-#include "util-inl.h"
-#include "async_wrap.h"
 #include "async_wrap-inl.h"
 
 #if NODE_USE_V8_PLATFORM && HAVE_INSPECTOR
diff --git a/src/node_zlib.cc b/src/node_zlib.cc
index badac08449ee6b..ea8b0e2a7637ed 100644
--- a/src/node_zlib.cc
+++ b/src/node_zlib.cc
@@ -32,10 +32,11 @@
 #include "brotli/decode.h"
 #include "zlib.h"
 
+#include <sys/types.h>
+
 #include <cerrno>
 #include <cstdlib>
 #include <cstring>
-#include <sys/types.h>
 #include <atomic>
 
 namespace node {
diff --git a/src/sharedarraybuffer_metadata.cc b/src/sharedarraybuffer_metadata.cc
index 5c58fac3ccf257..722a20065f308e 100644
--- a/src/sharedarraybuffer_metadata.cc
+++ b/src/sharedarraybuffer_metadata.cc
@@ -1,10 +1,10 @@
 #include "sharedarraybuffer_metadata.h"
 
-#include <utility>
-#include "base_object.h"
 #include "base_object-inl.h"
 #include "node_errors.h"
 
+#include <utility>
+
 using v8::Context;
 using v8::Function;
 using v8::FunctionTemplate;
diff --git a/src/stream_base.cc b/src/stream_base.cc
index 8eccca1a3e87a1..7aef9ba96d14a0 100644
--- a/src/stream_base.cc
+++ b/src/stream_base.cc
@@ -1,3 +1,4 @@
+#include "stream_base.h"  // NOLINT(build/include_inline)
 #include "stream_base-inl.h"
 #include "stream_wrap.h"
 
diff --git a/src/string_decoder.cc b/src/string_decoder.cc
index 1441ca86936a5a..90ceb2c222e319 100644
--- a/src/string_decoder.cc
+++ b/src/string_decoder.cc
@@ -1,7 +1,9 @@
+#include "string_decoder.h"  // NOLINT(build/include_inline)
+#include "string_decoder-inl.h"
+
 #include "env-inl.h"
 #include "node_buffer.h"
 #include "string_bytes.h"
-#include "string_decoder-inl.h"
 
 using v8::Array;
 using v8::ArrayBufferView;
diff --git a/src/tracing/node_trace_writer.cc b/src/tracing/node_trace_writer.cc
index 3b07504acc44ee..8f053efe93324b 100644
--- a/src/tracing/node_trace_writer.cc
+++ b/src/tracing/node_trace_writer.cc
@@ -1,10 +1,10 @@
 #include "tracing/node_trace_writer.h"
 
-#include <cstring>
-#include <fcntl.h>
-
 #include "util-inl.h"
 
+#include <fcntl.h>
+#include <cstring>
+
 namespace node {
 namespace tracing {
 
diff --git a/src/tracing/traced_value.cc b/src/tracing/traced_value.cc
index 3eb21a11c939d7..df4d862fb6b9c2 100644
--- a/src/tracing/traced_value.cc
+++ b/src/tracing/traced_value.cc
@@ -4,16 +4,16 @@
 
 #include "tracing/traced_value.h"
 
-#include <cmath>
-#include <sstream>
-#include <cstdio>
-#include <string>
-
 #if defined(NODE_HAVE_I18N_SUPPORT)
 #include <unicode/utf8.h>
 #include <unicode/utypes.h>
 #endif
 
+#include <cmath>
+#include <cstdio>
+#include <sstream>
+#include <string>
+
 #if defined(_STLP_VENDOR_CSTD)
 // STLPort doesn't import fpclassify into the std namespace.
 #define FPCLASSIFY_NAMESPACE
diff --git a/src/util.cc b/src/util.cc
index 223e0e87720853..f070401934f78b 100644
--- a/src/util.cc
+++ b/src/util.cc
@@ -19,14 +19,17 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-#include <cstdio>
-#include <sstream>
+#include "util.h"
+
 #include "node_buffer.h"
 #include "node_errors.h"
 #include "node_internals.h"
 #include "string_bytes.h"
 #include "uv.h"
 
+#include <cstdio>
+#include <sstream>
+
 namespace node {
 
 using v8::ArrayBufferView;
diff --git a/test/cctest/test_util.cc b/test/cctest/test_util.cc
index db19d92cbd9c19..7a0da1e6185d51 100644
--- a/test/cctest/test_util.cc
+++ b/test/cctest/test_util.cc
@@ -1,6 +1,4 @@
-#include "util.h"
 #include "util-inl.h"
-
 #include "gtest/gtest.h"
 
 TEST(UtilTest, ListHead) {
diff --git a/test/node-api/test_uv_loop/test_uv_loop.cc b/test/node-api/test_uv_loop/test_uv_loop.cc
index c5eaac52736240..51b10f32bb7900 100644
--- a/test/node-api/test_uv_loop/test_uv_loop.cc
+++ b/test/node-api/test_uv_loop/test_uv_loop.cc
@@ -1,9 +1,11 @@
+#include "../../js-native-api/common.h"
+
 #include <node_api.h>
 #include <uv.h>
-#include <utility>
+
+#include <cassert>
 #include <memory>
-#include <assert.h>
-#include "../../js-native-api/common.h"
+#include <utility>
 
 template <typename T>
 void* SetImmediate(napi_env env, T&& cb) {