diff --git a/code/espurna/config/all.h b/code/espurna/config/all.h
index dfa31e3f..36442202 100644
--- a/code/espurna/config/all.h
+++ b/code/espurna/config/all.h
@@ -34,3 +34,5 @@
 #ifdef USE_CORE_VERSION_H
 #include "core_version.h"
 #endif
+
+#include "build.h"
diff --git a/code/espurna/config/build.h b/code/espurna/config/build.h
new file mode 100644
index 00000000..04cd6f8d
--- /dev/null
+++ b/code/espurna/config/build.h
@@ -0,0 +1,3 @@
+// DO NOT EDIT THIS FILE MANUALLY
+// This file is modified by PlatformIO
+#define APP_BUILD_FLAGS "-g -DMQTT_MAX_PACKET_SIZE=400  -DWEMOS_D1_MINI_RELAYSHIELD -DDEBUG_FAUXMO=Serial -DNOWSAUTH"
\ No newline at end of file
diff --git a/code/espurna/mdns.ino b/code/espurna/mdns.ino
index c82f328a..be9ea215 100644
--- a/code/espurna/mdns.ino
+++ b/code/espurna/mdns.ino
@@ -67,6 +67,9 @@ void mdnsServerSetup() {
         itoa(ESP.getFreeSketchSpace(), buffer, 10);
         MDNS.addServiceTxt("arduino", "tcp", "free_space", (const char *) buffer);
     }
+    #ifdef APP_BUILD_FLAGS
+        //MDNS.addServiceTxt("arduino", "tcp", "build_flags", APP_BUILD_FLAGS);
+    #endif
 
     wifiRegister([](justwifi_messages_t code, char * parameter) {
 
diff --git a/code/espurna/utils.ino b/code/espurna/utils.ino
index 467c4bd9..8f8566e6 100644
--- a/code/espurna/utils.ino
+++ b/code/espurna/utils.ino
@@ -252,6 +252,9 @@ void info() {
 
     // -------------------------------------------------------------------------
 
+    #ifdef APP_BUILD_FLAGS
+        DEBUG_MSG_P(PSTR("[INIT] BUILD_FLAGS: %s\n"), APP_BUILD_FLAGS);
+    #endif
     DEBUG_MSG_P(PSTR("[INIT] BOARD: %s\n"), getBoardName().c_str());
     DEBUG_MSG_P(PSTR("[INIT] SUPPORT:"));
 
diff --git a/code/extra_scripts.py b/code/extra_scripts.py
index c981db86..43e54ec4 100644
--- a/code/extra_scripts.py
+++ b/code/extra_scripts.py
@@ -39,8 +39,21 @@ def check_size(source, target, env):
     #    print clr(Color.LIGHT_RED, "File too large for OTA!")
     #    Exit(1)
 
+def add_build_flags(source, target, env):
+    build_h = "espurna/config/build.h"
+    build_flags = env['BUILD_FLAGS'][0]
+    lines = open(build_h).readlines()
+    with open(build_h, "w") as fh:
+        for line in lines:
+            if "APP_BUILD_FLAGS" in line:
+                fh.write("#define APP_BUILD_FLAGS \"%s\"" % build_flags)
+            else:
+                fh.write(line)
+
+
 # ------------------------------------------------------------------------------
 # Hooks
 # ------------------------------------------------------------------------------
 
+env.AddPreAction("$BUILD_DIR/src/espurna.ino.o", add_build_flags)
 env.AddPostAction("$BUILD_DIR/${PROGNAME}.bin", check_size)