diff --git a/simulator/simulator/adc_inputs.h b/simulator/simulator/adc_inputs.h
index ffc9bea71f..b81afd9d9e 100644
--- a/simulator/simulator/adc_inputs.h
+++ b/simulator/simulator/adc_inputs.h
@@ -5,9 +5,7 @@
  * @author Andrey Belomutskiy, (c) 2012-2020
  */
 
-#ifndef ADC_INPUTS_H_
-#define ADC_INPUTS_H_
+#pragma once
 
 #include "adc_math.h"
 
-#endif /* ADC_INPUTS_H_ */
diff --git a/simulator/simulator/boards.h b/simulator/simulator/boards.h
index 1f39606f55..b930a769ab 100644
--- a/simulator/simulator/boards.h
+++ b/simulator/simulator/boards.h
@@ -1,6 +1,5 @@
 
-#ifndef BOARDS_FT_H_
-#define BOARDS_FT_H_
+#pragma once
 
 #define ADC_LOGIC_TPS 0
 #define ADC_LOGIC_AFR 0
@@ -52,4 +51,3 @@ extern "C"
 }
 #endif /* __cplusplus */
 
-#endif /* BOARDS_FT_H_ */
diff --git a/simulator/simulator/efifeatures.h b/simulator/simulator/efifeatures.h
index d1499e4d3f..1f7ec3f885 100644
--- a/simulator/simulator/efifeatures.h
+++ b/simulator/simulator/efifeatures.h
@@ -5,8 +5,7 @@
  * @author Andrey Belomutskiy, (c) 2012-2020
  */
 
-#ifndef EFIFEATURES_H_
-#define EFIFEATURES_H_
+#pragma once
 
 #include "rusefi_true.h"
 
@@ -147,6 +146,3 @@
 
 #define EFI_BOARD_TEST FALSE
 #define EFI_JOYSTICK FALSE
-
-
-#endif /* EFIFEATURES_H_ */
diff --git a/simulator/simulator/framework.h b/simulator/simulator/framework.h
index dc5d42c520..558cc3de7f 100644
--- a/simulator/simulator/framework.h
+++ b/simulator/simulator/framework.h
@@ -4,8 +4,8 @@
  * @date Sep 25, 2014
  * @author Andrey Belomutskiy, (c) 2012-2014
  */
-#ifndef FRAMEWORK_H_
-#define FRAMEWORK_H_
+
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -18,4 +18,3 @@ void initTestStream(BaseChannel *ts);
 }
 #endif /* __cplusplus */
 
-#endif /* FRAMEWORK_H_ */
diff --git a/simulator/simulator/global.h b/simulator/simulator/global.h
index 21be30174d..dc1a498826 100644
--- a/simulator/simulator/global.h
+++ b/simulator/simulator/global.h
@@ -7,8 +7,7 @@
  * @author Andrey Belomutskiy, (c) 2012-2020
  */
 
-#ifndef GLOBAL_H_
-#define GLOBAL_H_
+#pragma once
 
 #include <hal.h>
 
@@ -78,6 +77,3 @@ void applyNewConfiguration(void);
 
 #define hal_lld_get_counter_value() 0
 
-#endif /* GLOBAL_H_ */
-
-
diff --git a/simulator/simulator/os_access.h b/simulator/simulator/os_access.h
index 2a60d97240..dcfd7d8648 100644
--- a/simulator/simulator/os_access.h
+++ b/simulator/simulator/os_access.h
@@ -7,8 +7,7 @@
  * @author Andrey Belomutskiy, (c) 2012-2020
  */
 
-#ifndef OS_ACCESS_H_
-#define OS_ACCESS_H_
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -24,4 +23,3 @@ extern "C"
 
 #define HAS_OS_ACCESS
 
-#endif /* OS_ACCESS_H_ */
diff --git a/simulator/simulator/rusEfiFunctionalTest.h b/simulator/simulator/rusEfiFunctionalTest.h
index cd31068ece..94dcf83727 100644
--- a/simulator/simulator/rusEfiFunctionalTest.h
+++ b/simulator/simulator/rusEfiFunctionalTest.h
@@ -5,8 +5,7 @@
  * @author Andrey Belomutskiy, (c) 2012-2020
  */
 
-#ifndef RUSEFIFUNCTIONALTEST_H_
-#define RUSEFIFUNCTIONALTEST_H_
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -20,5 +19,3 @@ void logMsg(const char *fmt, ...);
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */
-
-#endif /* RUSEFIFUNCTIONALTEST_H_ */