diff --git a/firmware/controllers/algo/obd_error_codes.h b/firmware/controllers/algo/obd_error_codes.h
index 92dd57942d..5c76927fab 100644
--- a/firmware/controllers/algo/obd_error_codes.h
+++ b/firmware/controllers/algo/obd_error_codes.h
@@ -2072,7 +2072,7 @@ typedef enum {
 	CUSTOM_ERR_6706 = 6706,
 	CUSTOM_ERR_TIMER_TEST_CALLBACK_NOT_HAPPENED = 6707,
 	CUSTOM_ERR_TIMER_TEST_CALLBACK_WRONG_TIME = 6708,
-	CUSTOM_ERR_PIN_COUNT_TOO_LARGE = 6709,
+	CUSTOM_ERR_6709 = 6709,
 	CUSTOM_DUTY_INVALID = 6710,
 	CUSTOM_DUTY_TOO_HIGH = 6711,
 	CUSTOM_ERR_PWM_STATE_ASSERT = 6712,
diff --git a/firmware/controllers/system/efi_gpio.cpp b/firmware/controllers/system/efi_gpio.cpp
index dc0797cca5..01446a9d0d 100644
--- a/firmware/controllers/system/efi_gpio.cpp
+++ b/firmware/controllers/system/efi_gpio.cpp
@@ -52,18 +52,20 @@ EnginePins::EnginePins() {
 	dizzyOutput.name = PROTOCOL_DIZZY_NAME;
 	tachOut.name = PROTOCOL_TACH_NAME;
 
-	efiAssertVoid(CUSTOM_ERR_PIN_COUNT_TOO_LARGE, (sizeof(sparkNames) / sizeof(char*)) >= IGNITION_PIN_COUNT, "spark pin count");
+	static_assert(efi::size(sparkNames) >= IGNITION_PIN_COUNT, "Too many ignition pins");
 	for (int i = 0; i < IGNITION_PIN_COUNT;i++) {
 		enginePins.coils[i].name = sparkNames[i];
 		enginePins.coils[i].shortName = sparkShortNames[i];
 	}
-	efiAssertVoid(CUSTOM_ERR_PIN_COUNT_TOO_LARGE, (sizeof(injectorNames) / sizeof(char*)) >= INJECTION_PIN_COUNT, "inj pin count");
+
+	static_assert(efi::size(injectorNames) >= INJECTION_PIN_COUNT, "Too many injection pins");
 	for (int i = 0; i < INJECTION_PIN_COUNT;i++) {
 		enginePins.injectors[i].injectorIndex = i;
 		enginePins.injectors[i].name = injectorNames[i];
 		enginePins.injectors[i].shortName = injectorShortNames[i];
 	}
-	efiAssertVoid(CUSTOM_ERR_PIN_COUNT_TOO_LARGE, (sizeof(auxValveShortNames) / sizeof(char*)) >= AUX_DIGITAL_VALVE_COUNT, "aux pin count");
+
+	static_assert(efi::size(auxValveShortNames) >= AUX_DIGITAL_VALVE_COUNT, "Too many aux valve pins");
 	for (int i = 0; i < AUX_DIGITAL_VALVE_COUNT;i++) {
 		enginePins.auxValve[i].name = auxValveShortNames[i];
 	}
diff --git a/firmware/util/efilib.h b/firmware/util/efilib.h
index 9706e396ea..620117ed22 100644
--- a/firmware/util/efilib.h
+++ b/firmware/util/efilib.h
@@ -74,6 +74,17 @@ float expf_taylor(float x);
 
 #ifdef __cplusplus
 }
+
+// C++ helpers go here
+namespace efi
+{
+template <class T, size_t N>
+constexpr size_t size(const T (&)[N])
+{
+    return N;
+}
+} // namespace efi
+
 #endif /* __cplusplus */
 
 #endif /* EFILIB_H_ */