diff --git a/include/bmesensor.h b/include/bmesensor.h
index 5724db84..a038994e 100644
--- a/include/bmesensor.h
+++ b/include/bmesensor.h
@@ -1,6 +1,8 @@
 #ifndef _BMESENSOR_H
 #define _BMESENSOR_H
 
+#if (HAS_BME)
+
 #include <Wire.h>
 
 #include "globals.h"
@@ -53,4 +55,6 @@ int checkIaqSensorStatus(void);
 void loadState(void);
 void updateState(void);
 
+#endif
+
 #endif
\ No newline at end of file
diff --git a/include/dcf77.h b/include/dcf77.h
index df9400e9..6844c1b7 100644
--- a/include/dcf77.h
+++ b/include/dcf77.h
@@ -1,6 +1,8 @@
 #ifndef _DCF77_H
 #define _DCF77_H
 
+#ifdef HAS_DCF77
+
 #include "globals.h"
 #include "timekeeper.h"
 
@@ -15,4 +17,6 @@ enum dcf_pinstate { dcf_low, dcf_high };
 void DCF77_Pulse(uint8_t bit);
 uint64_t DCF77_Frame(const struct tm t);
 
+#endif
+
 #endif
\ No newline at end of file
diff --git a/include/gpsread.h b/include/gpsread.h
index 95cd1afa..6eae7bb7 100644
--- a/include/gpsread.h
+++ b/include/gpsread.h
@@ -1,6 +1,8 @@
 #ifndef _GPSREAD_H
 #define _GPSREAD_H
 
+#if (HAS_GPS)
+
 #include <TinyGPS++.h> // library for parsing NMEA data
 #include <RtcDateTime.h>
 #include "timekeeper.h"
@@ -19,4 +21,6 @@ void gps_storelocation(gpsStatus_t *gps_store);
 void gps_loop(void *pvParameters);
 time_t get_gpstime(uint16_t *msec);
 
+#endif
+
 #endif
\ No newline at end of file
diff --git a/include/if482.h b/include/if482.h
index 9a3fe92f..4efdbd3f 100644
--- a/include/if482.h
+++ b/include/if482.h
@@ -1,6 +1,8 @@
 #ifndef _IF482_H
 #define _IF482_H
 
+#ifdef HAS_IF482
+
 #include "globals.h"
 #include "timekeeper.h"
 #include "esp_sntp.h"
@@ -10,4 +12,6 @@
 
 String IF482_Frame(time_t t);
 
+#endif
+
 #endif
\ No newline at end of file
diff --git a/include/ledmatrixdisplay.h b/include/ledmatrixdisplay.h
index b27914c1..57b323c0 100644
--- a/include/ledmatrixdisplay.h
+++ b/include/ledmatrixdisplay.h
@@ -1,6 +1,8 @@
 #ifndef _MATRIX_DISPLAY_H
 #define _MATRIX_DISPLAY_H
 
+#ifdef HAS_MATRIX_DISPLAY
+
 #include "LEDMatrix.h"
 #include "ledmatrixfonts.h"
 #include "ledmatrixdisplay.h"
@@ -16,4 +18,6 @@ uint8_t GetCharFromFont(char cChar);
 uint8_t GetCharWidth(char cChar);
 void ScrollMatrixLeft(uint8_t *buf, const uint16_t cols, const uint16_t rows);
 
+#endif
+
 #endif
\ No newline at end of file
diff --git a/include/mqttclient.h b/include/mqttclient.h
index 6151dd52..cfdad89f 100644
--- a/include/mqttclient.h
+++ b/include/mqttclient.h
@@ -1,6 +1,8 @@
 #ifndef _MQTTCLIENT_H
 #define _MQTTCLIENT_H
 
+#ifdef HAS_MQTT
+
 #include "globals.h"
 #include "rcommand.h"
 #include "hash.h"
@@ -24,4 +26,6 @@ void NetworkEvent(WiFiEvent_t event);
 esp_err_t mqtt_init(void);
 void mqtt_deinit(void);
 
+#endif
+
 #endif // _MQTTCLIENT_H
\ No newline at end of file
diff --git a/include/power.h b/include/power.h
index 0e123c98..24f6fb67 100644
--- a/include/power.h
+++ b/include/power.h
@@ -3,7 +3,6 @@
 
 #include <Arduino.h>
 #include <esp_adc_cal.h>
-//include <esp32-hal-adc.h>
 #include <soc/adc_channel.h>
 
 #include "i2c.h"
@@ -56,7 +55,6 @@ void calibrate_voltage(void);
 bool batt_sufficient(void);
 
 #ifdef HAS_PMU
-
 #include <axp20x.h>
 extern AXP20X_Class pmu;
 enum pmu_power_t { pmu_power_on, pmu_power_off, pmu_power_sleep };
@@ -64,7 +62,6 @@ void AXP192_powerevent_IRQ(void);
 void AXP192_power(pmu_power_t powerlevel);
 void AXP192_init(void);
 void AXP192_showstatus(void);
-
 #endif // HAS_PMU
 
 #ifdef HAS_IP5306
diff --git a/include/rtctime.h b/include/rtctime.h
index 3f75eb37..802b06ee 100644
--- a/include/rtctime.h
+++ b/include/rtctime.h
@@ -1,6 +1,8 @@
 #ifndef _RTCTIME_H
 #define _RTCTIME_H
 
+#ifdef HAS_RTC
+
 #include <Wire.h> // must be included here so that Arduino library object file references work
 #include <RtcDS3231.h>
 
@@ -15,4 +17,6 @@ void sync_rtctime(void);
 time_t get_rtctime(uint16_t *msec);
 float get_rtctemp(void);
 
+#endif
+
 #endif // _RTCTIME_H
\ No newline at end of file
diff --git a/include/sdcard.h b/include/sdcard.h
index 25fcf2c4..1c9eb3d7 100644
--- a/include/sdcard.h
+++ b/include/sdcard.h
@@ -1,11 +1,12 @@
 #ifndef _SDCARD_H
 #define _SDCARD_H
 
+#if (HAS_SDCARD)
+
 #include "globals.h"
 #include <stdio.h>
 #include <SPI.h>
 
-#if (HAS_SDCARD)
 #if HAS_SDCARD == 1
 #include <SD.h>
 #elif HAS_SDCARD == 2
@@ -13,7 +14,6 @@
 #else
 #error HAS_SDCARD unknown card reader value, must be either 1 or 2
 #endif
-#endif
 
 #ifdef HAS_SDS011
 #include "sds011read.h"
@@ -65,4 +65,6 @@ bool sdcard_init(bool create = true);
 void sdcard_close(void);
 void sdcardWriteData(uint16_t, uint16_t, uint16_t = 0);
 
+#endif
+
 #endif // _SDCARD_H
diff --git a/include/sds011read.h b/include/sds011read.h
index f1b874d3..6345a267 100644
--- a/include/sds011read.h
+++ b/include/sds011read.h
@@ -1,10 +1,12 @@
 #ifndef _SDS011READ_H
 #define _SDS011READ_H
 
+#if (HAS_SDS011)
+
 #include <SdsDustSensor.h>
 #include "globals.h"
 
-#define SDCARD_FILE_HEADER_SDS011     ", PM10,PM25"
+#define SDCARD_FILE_HEADER_SDS011 ", PM10,PM25"
 
 // use original pins from HardwareSerial if none defined
 #ifndef SDS_TX
@@ -21,4 +23,7 @@ void sds011_loop();
 void sds011_sleep(void);
 void sds011_wakeup(void);
 void sds011_store(sdsStatus_t *sds_store);
+
+#endif
+
 #endif // _SDS011READ_H
diff --git a/include/spislave.h b/include/spislave.h
index 78b7a737..389aa573 100644
--- a/include/spislave.h
+++ b/include/spislave.h
@@ -24,6 +24,8 @@ licenses. Refer to LICENSE.txt file in repository for more details.
 #ifndef _SPISLAVE_H
 #define _SPISLAVE_H
 
+#ifdef HAS_SPI
+
 #include "globals.h"
 #include "rcommand.h"
 
@@ -35,4 +37,6 @@ void spi_enqueuedata(MessageBuffer_t *message);
 uint32_t spi_queuewaiting(void);
 void spi_queuereset(void);
 
+#endif
+
 #endif // _SPISLAVE_H
diff --git a/src/rtctime.cpp b/src/rtctime.cpp
index eb25698d..9b12cd94 100644
--- a/src/rtctime.cpp
+++ b/src/rtctime.cpp
@@ -1,10 +1,10 @@
+#ifdef HAS_RTC // we have hardware RTC
+
 #include "rtctime.h"
 
 // Local logging tag
 static const char TAG[] = __FILE__;
 
-#ifdef HAS_RTC // we have hardware RTC
-
 RtcDS3231<TwoWire> Rtc(Wire); // RTC hardware i2c interface
 
 // initialize RTC