diff --git a/Makefile b/Makefile
index 914f1b31..a1d8c88b 100644
--- a/Makefile
+++ b/Makefile
@@ -125,7 +125,7 @@ mongoose.c: Makefile $(wildcard src/*)
 	(cat src/license.h; echo; echo '#include "mongoose.h"' ; (for F in src/*.c ; do echo; echo '#ifdef MG_ENABLE_LINES'; echo "#line 1 \"$$F\""; echo '#endif'; cat $$F | sed -e 's,#include ".*,,'; done))> $@
 
 mongoose.h: $(HDRS) Makefile
-	(cat src/license.h; echo; echo '#ifndef MONGOOSE_H'; echo '#define MONGOOSE_H'; echo; cat src/version.h ; echo; echo '#ifdef __cplusplus'; echo 'extern "C" {'; echo '#endif'; cat src/config.h src/arch.h src/arch_*.h src/str.h src/log.h src/timer.h src/util.h src/fs.h src/url.h src/iobuf.h src/base64.h src/md5.h src/sha1.h src/event.h src/net.h src/http.h src/ssi.h src/tls.h src/tls_mbed.h src/tls_openssl.h src/ws.h src/sntp.h src/mqtt.h src/dns.h | sed -e 's,#include ".*,,' -e 's,^#pragma once,,'; echo; echo '#ifdef __cplusplus'; echo '}'; echo '#endif'; echo '#endif  // MONGOOSE_H')> $@
+	(cat src/license.h; echo; echo '#ifndef MONGOOSE_H'; echo '#define MONGOOSE_H'; echo; cat src/version.h ; echo; echo '#ifdef __cplusplus'; echo 'extern "C" {'; echo '#endif'; cat src/arch.h src/arch_*.h src/config.h src/str.h src/log.h src/timer.h src/util.h src/fs.h src/url.h src/iobuf.h src/base64.h src/md5.h src/sha1.h src/event.h src/net.h src/http.h src/ssi.h src/tls.h src/tls_mbed.h src/tls_openssl.h src/ws.h src/sntp.h src/mqtt.h src/dns.h | sed -e 's,#include ".*,,' -e 's,^#pragma once,,'; echo; echo '#ifdef __cplusplus'; echo '}'; echo '#endif'; echo '#endif  // MONGOOSE_H')> $@
 
 clean:
 	rm -rf $(PROG) *.o *.dSYM unit_test* ut fuzzer *.gcov *.gcno *.gcda *.obj *.exe *.ilk *.pdb slow-unit* _CL_* infer-out data.txt crash-* test/packed_fs.c pack
diff --git a/mongoose.c b/mongoose.c
index 0be9e235..39a5b1f4 100644
--- a/mongoose.c
+++ b/mongoose.c
@@ -515,7 +515,7 @@ struct mg_fs mg_fs_packed = {packed_stat,  packed_list, packed_open,
 #endif
 
 
-#if defined(FOPEN_MAX)
+#if MG_ENABLE_FILE
 static int p_stat(const char *path, size_t *size, time_t *mtime) {
 #ifdef _WIN32
   struct _stati64 st;
@@ -691,9 +691,9 @@ static size_t p_write(void *fp, const void *buf, size_t len) {
 }
 
 static size_t p_seek(void *fp, size_t offset) {
-#if (defined(_FILE_OFFSET_BITS) && _FILE_OFFSET_BITS == 64) || \
-  (defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 200112L) || \
-  (defined(_XOPEN_SOURCE) && _XOPEN_SOURCE >= 600)
+#if (defined(_FILE_OFFSET_BITS) && _FILE_OFFSET_BITS == 64) ||  \
+    (defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 200112L) || \
+    (defined(_XOPEN_SOURCE) && _XOPEN_SOURCE >= 600)
   fseeko((FILE *) fp, (off_t) offset, SEEK_SET);
 #else
   fseek((FILE *) fp, (long) offset, SEEK_SET);
@@ -1127,6 +1127,7 @@ char *mg_http_etag(char *buf, size_t len, size_t size, time_t mtime) {
   return buf;
 }
 
+#if MG_ENABLE_FILE
 int mg_http_upload(struct mg_connection *c, struct mg_http_message *hm,
                    const char *dir) {
   char offset[40] = "", name[200] = "", path[256];
@@ -1152,6 +1153,7 @@ int mg_http_upload(struct mg_connection *c, struct mg_http_message *hm,
     }
   }
 }
+#endif
 
 static void static_cb(struct mg_connection *c, int ev, void *ev_data,
                       void *fn_data) {
@@ -1796,7 +1798,9 @@ void mg_iobuf_free(struct mg_iobuf *io) {
 #if MG_ENABLE_LOG
 static void mg_log_stdout(const void *buf, size_t len, void *userdata) {
   (void) userdata;
+#if MG_ENABLE_FILE
   fwrite(buf, 1, len, stdout);
+#endif
 }
 
 static const char *s_spec = "2";
@@ -4163,6 +4167,7 @@ struct mg_str mg_url_pass(const char *url) {
 #include <mach/mach_time.h>
 #endif
 
+#if MG_ENABLE_FILE
 char *mg_file_read(const char *path, size_t *sizep) {
   FILE *fp;
   char *data = NULL;
@@ -4204,6 +4209,7 @@ bool mg_file_write(const char *path, const void *buf, size_t len) {
   }
   return result;
 }
+#endif
 
 bool mg_file_printf(const char *path, const char *fmt, ...) {
   char tmp[256], *buf = tmp;
@@ -4512,8 +4518,8 @@ unsigned long mg_millis(void) {
   uint64_t ticks = mach_absolute_time();
   static mach_timebase_info_data_t timebase;
   mach_timebase_info(&timebase);
-  double ticks_to_nanos = (double)timebase.numer / timebase.denom;
-  uint64_t uptime_nanos = (uint64_t)(ticks_to_nanos * ticks);
+  double ticks_to_nanos = (double) timebase.numer / timebase.denom;
+  uint64_t uptime_nanos = (uint64_t) (ticks_to_nanos * ticks);
   return (unsigned long) (uptime_nanos / 1000000);
 #else
   struct timespec ts;
diff --git a/mongoose.h b/mongoose.h
index 90a8a1f4..4c9202eb 100644
--- a/mongoose.h
+++ b/mongoose.h
@@ -25,82 +25,6 @@ extern "C" {
 #endif
 
 
-#ifndef MG_ENABLE_SOCKET
-#define MG_ENABLE_SOCKET 1
-#endif
-
-#ifndef MG_ENABLE_MBEDTLS
-#define MG_ENABLE_MBEDTLS 0
-#endif
-
-#ifndef MG_ENABLE_OPENSSL
-#define MG_ENABLE_OPENSSL 0
-#endif
-
-#ifndef MG_ENABLE_CUSTOM_TLS
-#define MG_ENABLE_CUSTOM_TLS 0
-#endif
-
-#ifndef MG_ENABLE_SSI
-#define MG_ENABLE_SSI 1
-#endif
-
-#ifndef MG_ENABLE_IPV6
-#define MG_ENABLE_IPV6 0
-#endif
-
-#ifndef MG_ENABLE_LOG
-#define MG_ENABLE_LOG 1
-#endif
-
-#ifndef MG_ENABLE_MD5
-#define MG_ENABLE_MD5 0
-#endif
-
-// Set MG_ENABLE_WINSOCK=0 for Win32 builds with external IP stack (like LWIP)
-#ifndef MG_ENABLE_WINSOCK
-#define MG_ENABLE_WINSOCK 1
-#endif
-
-#ifndef MG_ENABLE_DIRLIST
-#define MG_ENABLE_DIRLIST 0
-#endif
-
-#ifndef MG_ENABLE_CUSTOM_RANDOM
-#define MG_ENABLE_CUSTOM_RANDOM 0
-#endif
-
-#ifndef MG_ENABLE_PACKED_FS
-#define MG_ENABLE_PACKED_FS 0
-#endif
-
-// Granularity of the send/recv IO buffer growth
-#ifndef MG_IO_SIZE
-#define MG_IO_SIZE 2048
-#endif
-
-// Maximum size of the recv IO buffer
-#ifndef MG_MAX_RECV_BUF_SIZE
-#define MG_MAX_RECV_BUF_SIZE (3 * 1024 * 1024)
-#endif
-
-#ifndef MG_MAX_HTTP_HEADERS
-#define MG_MAX_HTTP_HEADERS 40
-#endif
-
-#ifndef MG_HTTP_INDEX
-#define MG_HTTP_INDEX "index.html"
-#endif
-
-#ifndef MG_PATH_MAX
-#define MG_PATH_MAX PATH_MAX
-#endif
-
-#ifndef MG_SOCK_LISTEN_BACKLOG_SIZE
-#define MG_SOCK_LISTEN_BACKLOG_SIZE 128
-#endif
-
-
 #define MG_ARCH_CUSTOM 0
 #define MG_ARCH_UNIX 1
 #define MG_ARCH_WIN32 2
@@ -205,11 +129,6 @@ static __inline struct tm *localtime_r(time_t *t, struct tm *tm) {
 #include <sys/types.h>
 #include <time.h>
 
-#undef MG_PATH_MAX
-#undef MG_ENABLE_DIRLIST
-
-#define MG_DIRSEP '/'
-#define MG_INT64_FMT "%lld"
 #define MG_PATH_MAX 128
 #define MG_ENABLE_DIRLIST 1
 
@@ -237,11 +156,6 @@ static __inline struct tm *localtime_r(time_t *t, struct tm *tm) {
 
 #include <esp_system.h>
 
-#undef MG_PATH_MAX
-#undef MG_ENABLE_DIRLIST
-
-#define MG_DIRSEP '/'
-#define MG_INT64_FMT "%lld"
 #define MG_PATH_MAX 128
 #define MG_ENABLE_DIRLIST 1
 
@@ -321,9 +235,6 @@ static inline void *mg_calloc(int cnt, size_t size) {
 #include <FreeRTOS_Sockets.h>
 #include <task.h>
 
-#define MG_INT64_FMT "%lld"
-#define MG_DIRSEP '/'
-
 // Why FreeRTOS-TCP did not implement a clean BSD API, but its own thing
 // with FreeRTOS_ prefix, is beyond me
 #define IPPROTO_TCP FREERTOS_IPPROTO_TCP
@@ -418,9 +329,7 @@ struct timeval {
 #include <time.h>
 #include <unistd.h>
 
-#define MG_DIRSEP '/'
 #define MG_INT64_FMT "%" PRId64
-#undef MG_ENABLE_DIRLIST
 #define MG_ENABLE_DIRLIST 1
 
 #endif
@@ -525,6 +434,102 @@ static __inline struct tm *localtime_r(time_t *t, struct tm *tm) {
 #endif
 
 
+#ifndef MG_ENABLE_SOCKET
+#define MG_ENABLE_SOCKET 1
+#endif
+
+#ifndef MG_ENABLE_MBEDTLS
+#define MG_ENABLE_MBEDTLS 0
+#endif
+
+#ifndef MG_ENABLE_OPENSSL
+#define MG_ENABLE_OPENSSL 0
+#endif
+
+#ifndef MG_ENABLE_CUSTOM_TLS
+#define MG_ENABLE_CUSTOM_TLS 0
+#endif
+
+#ifndef MG_ENABLE_SSI
+#define MG_ENABLE_SSI 1
+#endif
+
+#ifndef MG_ENABLE_IPV6
+#define MG_ENABLE_IPV6 0
+#endif
+
+#ifndef MG_ENABLE_LOG
+#define MG_ENABLE_LOG 1
+#endif
+
+#ifndef MG_ENABLE_MD5
+#define MG_ENABLE_MD5 0
+#endif
+
+// Set MG_ENABLE_WINSOCK=0 for Win32 builds with external IP stack (like LWIP)
+#ifndef MG_ENABLE_WINSOCK
+#define MG_ENABLE_WINSOCK 1
+#endif
+
+#ifndef MG_ENABLE_DIRLIST
+#define MG_ENABLE_DIRLIST 0
+#endif
+
+#ifndef MG_ENABLE_CUSTOM_RANDOM
+#define MG_ENABLE_CUSTOM_RANDOM 0
+#endif
+
+#ifndef MG_ENABLE_PACKED_FS
+#define MG_ENABLE_PACKED_FS 0
+#endif
+
+// Granularity of the send/recv IO buffer growth
+#ifndef MG_IO_SIZE
+#define MG_IO_SIZE 2048
+#endif
+
+// Maximum size of the recv IO buffer
+#ifndef MG_MAX_RECV_BUF_SIZE
+#define MG_MAX_RECV_BUF_SIZE (3 * 1024 * 1024)
+#endif
+
+#ifndef MG_MAX_HTTP_HEADERS
+#define MG_MAX_HTTP_HEADERS 40
+#endif
+
+#ifndef MG_HTTP_INDEX
+#define MG_HTTP_INDEX "index.html"
+#endif
+
+#ifndef MG_PATH_MAX
+#ifdef PATH_MAX
+#define MG_PATH_MAX PATH_MAX
+#else
+#define MG_PATH_MAX 128
+#endif
+#endif
+
+#ifndef MG_SOCK_LISTEN_BACKLOG_SIZE
+#define MG_SOCK_LISTEN_BACKLOG_SIZE 128
+#endif
+
+#ifndef MG_DIRSEP
+#define MG_DIRSEP '/'
+#endif
+
+#ifndef MG_INT64_FMT
+#define MG_INT64_FMT "%lld"
+#endif
+
+#ifndef MG_ENABLE_FILE
+#if defined(FOPEN_MAX)
+#define MG_ENABLE_FILE 1
+#else
+#define MG_ENABLE_FILE 0
+#endif
+#endif
+
+
 #include <ctype.h>
 #include <string.h>
 
diff --git a/src/arch_esp32.h b/src/arch_esp32.h
index 650880a8..a6925a3c 100644
--- a/src/arch_esp32.h
+++ b/src/arch_esp32.h
@@ -17,11 +17,6 @@
 #include <sys/types.h>
 #include <time.h>
 
-#undef MG_PATH_MAX
-#undef MG_ENABLE_DIRLIST
-
-#define MG_DIRSEP '/'
-#define MG_INT64_FMT "%lld"
 #define MG_PATH_MAX 128
 #define MG_ENABLE_DIRLIST 1
 
diff --git a/src/arch_esp8266.h b/src/arch_esp8266.h
index a26b2626..8c00ec94 100644
--- a/src/arch_esp8266.h
+++ b/src/arch_esp8266.h
@@ -21,11 +21,6 @@
 
 #include <esp_system.h>
 
-#undef MG_PATH_MAX
-#undef MG_ENABLE_DIRLIST
-
-#define MG_DIRSEP '/'
-#define MG_INT64_FMT "%lld"
 #define MG_PATH_MAX 128
 #define MG_ENABLE_DIRLIST 1
 
diff --git a/src/arch_freertos_tcp.h b/src/arch_freertos_tcp.h
index 4bc6b4ab..db2c9147 100644
--- a/src/arch_freertos_tcp.h
+++ b/src/arch_freertos_tcp.h
@@ -19,9 +19,6 @@
 #include <FreeRTOS_Sockets.h>
 #include <task.h>
 
-#define MG_INT64_FMT "%lld"
-#define MG_DIRSEP '/'
-
 // Why FreeRTOS-TCP did not implement a clean BSD API, but its own thing
 // with FreeRTOS_ prefix, is beyond me
 #define IPPROTO_TCP FREERTOS_IPPROTO_TCP
diff --git a/src/arch_unix.h b/src/arch_unix.h
index cb6585f6..d74fe2df 100644
--- a/src/arch_unix.h
+++ b/src/arch_unix.h
@@ -29,9 +29,7 @@
 #include <time.h>
 #include <unistd.h>
 
-#define MG_DIRSEP '/'
 #define MG_INT64_FMT "%" PRId64
-#undef MG_ENABLE_DIRLIST
 #define MG_ENABLE_DIRLIST 1
 
 #endif
diff --git a/src/config.h b/src/config.h
index 153fbd74..8cad23eb 100644
--- a/src/config.h
+++ b/src/config.h
@@ -68,9 +68,29 @@
 #endif
 
 #ifndef MG_PATH_MAX
+#ifdef PATH_MAX
 #define MG_PATH_MAX PATH_MAX
+#else
+#define MG_PATH_MAX 128
+#endif
 #endif
 
 #ifndef MG_SOCK_LISTEN_BACKLOG_SIZE
 #define MG_SOCK_LISTEN_BACKLOG_SIZE 128
 #endif
+
+#ifndef MG_DIRSEP
+#define MG_DIRSEP '/'
+#endif
+
+#ifndef MG_INT64_FMT
+#define MG_INT64_FMT "%lld"
+#endif
+
+#ifndef MG_ENABLE_FILE
+#if defined(FOPEN_MAX)
+#define MG_ENABLE_FILE 1
+#else
+#define MG_ENABLE_FILE 0
+#endif
+#endif
diff --git a/src/fs_posix.c b/src/fs_posix.c
index d9b6d3ca..fa12c2cd 100644
--- a/src/fs_posix.c
+++ b/src/fs_posix.c
@@ -1,6 +1,6 @@
 #include "fs.h"
 
-#if defined(FOPEN_MAX)
+#if MG_ENABLE_FILE
 static int p_stat(const char *path, size_t *size, time_t *mtime) {
 #ifdef _WIN32
   struct _stati64 st;
@@ -176,9 +176,9 @@ static size_t p_write(void *fp, const void *buf, size_t len) {
 }
 
 static size_t p_seek(void *fp, size_t offset) {
-#if (defined(_FILE_OFFSET_BITS) && _FILE_OFFSET_BITS == 64) || \
-  (defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 200112L) || \
-  (defined(_XOPEN_SOURCE) && _XOPEN_SOURCE >= 600)
+#if (defined(_FILE_OFFSET_BITS) && _FILE_OFFSET_BITS == 64) ||  \
+    (defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 200112L) || \
+    (defined(_XOPEN_SOURCE) && _XOPEN_SOURCE >= 600)
   fseeko((FILE *) fp, (off_t) offset, SEEK_SET);
 #else
   fseek((FILE *) fp, (long) offset, SEEK_SET);
diff --git a/src/http.c b/src/http.c
index 87bbf570..f0f4e8ec 100644
--- a/src/http.c
+++ b/src/http.c
@@ -378,6 +378,7 @@ char *mg_http_etag(char *buf, size_t len, size_t size, time_t mtime) {
   return buf;
 }
 
+#if MG_ENABLE_FILE
 int mg_http_upload(struct mg_connection *c, struct mg_http_message *hm,
                    const char *dir) {
   char offset[40] = "", name[200] = "", path[256];
@@ -403,6 +404,7 @@ int mg_http_upload(struct mg_connection *c, struct mg_http_message *hm,
     }
   }
 }
+#endif
 
 static void static_cb(struct mg_connection *c, int ev, void *ev_data,
                       void *fn_data) {
diff --git a/src/log.c b/src/log.c
index 5c433b7c..cde69323 100644
--- a/src/log.c
+++ b/src/log.c
@@ -4,7 +4,9 @@
 #if MG_ENABLE_LOG
 static void mg_log_stdout(const void *buf, size_t len, void *userdata) {
   (void) userdata;
+#if MG_ENABLE_FILE
   fwrite(buf, 1, len, stdout);
+#endif
 }
 
 static const char *s_spec = "2";
diff --git a/src/util.c b/src/util.c
index 9eb8f615..8576d987 100644
--- a/src/util.c
+++ b/src/util.c
@@ -6,6 +6,7 @@
 #include <mach/mach_time.h>
 #endif
 
+#if MG_ENABLE_FILE
 char *mg_file_read(const char *path, size_t *sizep) {
   FILE *fp;
   char *data = NULL;
@@ -47,6 +48,7 @@ bool mg_file_write(const char *path, const void *buf, size_t len) {
   }
   return result;
 }
+#endif
 
 bool mg_file_printf(const char *path, const char *fmt, ...) {
   char tmp[256], *buf = tmp;
@@ -355,8 +357,8 @@ unsigned long mg_millis(void) {
   uint64_t ticks = mach_absolute_time();
   static mach_timebase_info_data_t timebase;
   mach_timebase_info(&timebase);
-  double ticks_to_nanos = (double)timebase.numer / timebase.denom;
-  uint64_t uptime_nanos = (uint64_t)(ticks_to_nanos * ticks);
+  double ticks_to_nanos = (double) timebase.numer / timebase.denom;
+  uint64_t uptime_nanos = (uint64_t) (ticks_to_nanos * ticks);
   return (unsigned long) (uptime_nanos / 1000000);
 #else
   struct timespec ts;
diff --git a/test/mongoose_custom.h b/test/mongoose_custom.h
index a01c66b1..522be510 100644
--- a/test/mongoose_custom.h
+++ b/test/mongoose_custom.h
@@ -15,9 +15,5 @@
 #include <time.h>
 #include <unistd.h>
 
-#define MG_DIRSEP '/'
-#define MG_INT64_FMT "%lld"
-#undef MG_PATH_MAX
 #define MG_PATH_MAX 100
-#undef MG_ENABLE_SOCKET
 #define MG_ENABLE_SOCKET 0