diff --git a/boards/px4/sitl/default.cmake b/boards/px4/sitl/default.cmake
index 923e61983c..8caa4b20e2 100644
--- a/boards/px4/sitl/default.cmake
+++ b/boards/px4/sitl/default.cmake
@@ -97,3 +97,6 @@ if(REPLAY_FILE)
 	message("Building with uorb publisher rules support")
 	add_definitions(-DORB_USE_PUBLISHER_RULES)
 endif()
+
+add_definitions(-D__PX4_POSIX_SITL)
+set(LOCKSTEP_SCHEDULER_NEEDED yes)
diff --git a/platforms/posix/src/CMakeLists.txt b/platforms/posix/src/CMakeLists.txt
index 00bab5f2de..646d3a9a0c 100644
--- a/platforms/posix/src/CMakeLists.txt
+++ b/platforms/posix/src/CMakeLists.txt
@@ -31,5 +31,9 @@
 #
 ############################################################################
 
+if (LOCKSTEP_SCHEDULER_NEEDED)
+	add_subdirectory(lockstep_scheduler)
+endif()
+
 add_subdirectory(px4_daemon)
 add_subdirectory(px4_layer)
diff --git a/src/platforms/posix/lockstep_scheduler/.gitignore b/platforms/posix/src/lockstep_scheduler/.gitignore
similarity index 100%
rename from src/platforms/posix/lockstep_scheduler/.gitignore
rename to platforms/posix/src/lockstep_scheduler/.gitignore
diff --git a/src/platforms/posix/lockstep_scheduler/CMakeLists.txt b/platforms/posix/src/lockstep_scheduler/CMakeLists.txt
similarity index 100%
rename from src/platforms/posix/lockstep_scheduler/CMakeLists.txt
rename to platforms/posix/src/lockstep_scheduler/CMakeLists.txt
diff --git a/src/platforms/posix/lockstep_scheduler/build-and-test.sh b/platforms/posix/src/lockstep_scheduler/build-and-test.sh
similarity index 100%
rename from src/platforms/posix/lockstep_scheduler/build-and-test.sh
rename to platforms/posix/src/lockstep_scheduler/build-and-test.sh
diff --git a/src/platforms/posix/lockstep_scheduler/include/lockstep_scheduler/lockstep_scheduler.h b/platforms/posix/src/lockstep_scheduler/include/lockstep_scheduler/lockstep_scheduler.h
similarity index 100%
rename from src/platforms/posix/lockstep_scheduler/include/lockstep_scheduler/lockstep_scheduler.h
rename to platforms/posix/src/lockstep_scheduler/include/lockstep_scheduler/lockstep_scheduler.h
diff --git a/src/platforms/posix/lockstep_scheduler/src/lockstep_scheduler.cpp b/platforms/posix/src/lockstep_scheduler/src/lockstep_scheduler.cpp
similarity index 100%
rename from src/platforms/posix/lockstep_scheduler/src/lockstep_scheduler.cpp
rename to platforms/posix/src/lockstep_scheduler/src/lockstep_scheduler.cpp
diff --git a/src/platforms/posix/lockstep_scheduler/test/CMakeLists.txt b/platforms/posix/src/lockstep_scheduler/test/CMakeLists.txt
similarity index 100%
rename from src/platforms/posix/lockstep_scheduler/test/CMakeLists.txt
rename to platforms/posix/src/lockstep_scheduler/test/CMakeLists.txt
diff --git a/src/platforms/posix/lockstep_scheduler/test/src/lockstep_scheduler_test.cpp b/platforms/posix/src/lockstep_scheduler/test/src/lockstep_scheduler_test.cpp
similarity index 100%
rename from src/platforms/posix/lockstep_scheduler/test/src/lockstep_scheduler_test.cpp
rename to platforms/posix/src/lockstep_scheduler/test/src/lockstep_scheduler_test.cpp
diff --git a/platforms/posix/src/px4_layer/CMakeLists.txt b/platforms/posix/src/px4_layer/CMakeLists.txt
index 7ce430ae0e..5ce8a3c4bd 100644
--- a/platforms/posix/src/px4_layer/CMakeLists.txt
+++ b/platforms/posix/src/px4_layer/CMakeLists.txt
@@ -58,7 +58,7 @@ target_link_libraries(px4_layer PRIVATE px4_daemon)
 
 if(LOCKSTEP_SCHEDULER_NEEDED)
 	target_link_libraries(px4_layer PRIVATE lockstep_scheduler)
-	include_directories(${PX4_SOURCE_DIR}/src/platforms/posix/lockstep_scheduler/include)
+	include_directories(${PX4_SOURCE_DIR}/platforms/posix/src/lockstep_scheduler/include)
 endif()