diff --git a/platforms/common/include/px4_platform_common/time.h b/platforms/common/include/px4_platform_common/time.h
index 793f65f2728..ba1b161c33c 100644
--- a/platforms/common/include/px4_platform_common/time.h
+++ b/platforms/common/include/px4_platform_common/time.h
@@ -5,10 +5,6 @@
 #include <time.h>
 #include <pthread.h>
 
-#if defined(__PX4_APPLE_LEGACY)
-#define clockid_t int
-#endif
-
 #if defined(__PX4_POSIX) || defined(__PX4_QURT)
 __BEGIN_DECLS
 __EXPORT int px4_clock_gettime(clockid_t clk_id, struct timespec *tp);
diff --git a/platforms/posix/cmake/px4_impl_os.cmake b/platforms/posix/cmake/px4_impl_os.cmake
index 8137c75d190..b334336ab4c 100644
--- a/platforms/posix/cmake/px4_impl_os.cmake
+++ b/platforms/posix/cmake/px4_impl_os.cmake
@@ -225,21 +225,6 @@ function(px4_os_add_flags)
 		if(UNIX AND APPLE)
 			add_definitions(-D__PX4_DARWIN)
 
-			if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 8.0)
-				message(FATAL_ERROR "PX4 Firmware requires XCode 8 or newer on Mac OS. Version installed on this system: ${CMAKE_CXX_COMPILER_VERSION}")
-			endif()
-
-			execute_process(COMMAND uname -v OUTPUT_VARIABLE DARWIN_VERSION)
-			string(REGEX MATCH "[0-9]+" DARWIN_VERSION ${DARWIN_VERSION})
-			# message(STATUS "PX4 Darwin Version: ${DARWIN_VERSION}")
-			if (DARWIN_VERSION LESS 16)
-				add_definitions(
-					-DCLOCK_MONOTONIC=1
-					-DCLOCK_REALTIME=0
-					-D__PX4_APPLE_LEGACY
-					)
-			endif()
-
 		elseif(CYGWIN)
 			add_definitions(
 				-D__PX4_CYGWIN
diff --git a/platforms/posix/src/px4/common/drv_hrt.cpp b/platforms/posix/src/px4/common/drv_hrt.cpp
index 349986ce6d3..c4a1d9b9dc0 100644
--- a/platforms/posix/src/px4/common/drv_hrt.cpp
+++ b/platforms/posix/src/px4/common/drv_hrt.cpp
@@ -95,31 +95,6 @@ static void hrt_unlock()
 	px4_sem_post(&_hrt_lock);
 }
 
-#if defined(__PX4_APPLE_LEGACY)
-#include <sys/time.h>
-
-int px4_clock_gettime(clockid_t clk_id, struct timespec *tp)
-{
-	struct timeval now;
-	int rv = gettimeofday(&now, nullptr);
-
-	if (rv) {
-		return rv;
-	}
-
-	tp->tv_sec = now.tv_sec;
-	tp->tv_nsec = now.tv_usec * 1000;
-
-	return 0;
-}
-
-int px4_clock_settime(clockid_t clk_id, struct timespec *tp)
-{
-	/* do nothing right now */
-	return 0;
-}
-#endif
-
 /*
  * Get absolute time.
  */
@@ -465,23 +440,15 @@ hrt_call_invoke()
 
 int px4_clock_gettime(clockid_t clk_id, struct timespec *tp)
 {
-	if (clk_id == CLOCK_MONOTONIC) {
 #if defined(ENABLE_LOCKSTEP_SCHEDULER)
+
+	if (clk_id == CLOCK_MONOTONIC) {
 		abstime_to_ts(tp, lockstep_scheduler.get_absolute_time());
 		return 0;
-#else // defined(ENABLE_LOCKSTEP_SCHEDULER)
-#if defined(__PX4_DARWIN)
-		// We don't have CLOCK_MONOTONIC on macOS, so we just have to
-		// resort back to CLOCK_REALTIME here.
-		return system_clock_gettime(CLOCK_REALTIME, tp);
-#else // defined(__PX4_DARWIN)
-		return system_clock_gettime(clk_id, tp);
-#endif // defined(__PX4_DARWIN)
-#endif // defined(ENABLE_LOCKSTEP_SCHEDULER)
-
-	} else {
-		return system_clock_gettime(clk_id, tp);
 	}
+
+#endif // defined(ENABLE_LOCKSTEP_SCHEDULER)
+	return system_clock_gettime(clk_id, tp);
 }
 
 #if defined(ENABLE_LOCKSTEP_SCHEDULER)