diff --git a/mods/ENTITIES/mcl_mobs/api.lua b/mods/ENTITIES/mcl_mobs/api.lua
index f02d5b4336..58fee205ff 100644
--- a/mods/ENTITIES/mcl_mobs/api.lua
+++ b/mods/ENTITIES/mcl_mobs/api.lua
@@ -228,6 +228,9 @@ end
 
 
 -- move mob in facing direction
+--this has been modified to be internal
+--internal = lua (self.yaw)
+--engine = c++ (self.object:get_yaw())
 local set_velocity = function(self, v)
 	
 	local yaw = (self.yaw or 0)
@@ -271,37 +274,6 @@ local get_velocity = function(self)
 	return 0
 end
 
-
--- set and return valid yaw
-local set_yaw = function(self, yaw, delay, dtime)
-
-	if not yaw or yaw ~= yaw then
-		yaw = 0
-	end
-
-	delay = delay or 0
-
-	if delay == 0 then
-		if self.shaking and dtime then
-			yaw = yaw + (math_random() * 2 - 1) * 5 * dtime
-		end
-		self.yaw(yaw)
-		update_roll(self)
-		return yaw
-	end
-
-	self.target_yaw = yaw
-	self.delay = delay
-
-	return self.target_yaw
-end
-
--- global function to set mob yaw
-function mobs:yaw(self, yaw, delay, dtime)
-	set_yaw(self, yaw, delay, dtime)
-end
-
-
 -- set defined animation
 local set_animation = function(self, anim, fixed_frame)
 	if not self.animation or not anim then
diff --git a/mods/ENTITIES/mcl_mobs/backup_code_api.lua b/mods/ENTITIES/mcl_mobs/backup_code_api.lua
index 97036fab81..eb1389e371 100644
--- a/mods/ENTITIES/mcl_mobs/backup_code_api.lua
+++ b/mods/ENTITIES/mcl_mobs/backup_code_api.lua
@@ -3266,4 +3266,34 @@ local create_mob_on_rightclick = function(on_rightclick)
 			on_rightclick(self, clicker)
 		end
 	end
-end
\ No newline at end of file
+end
+
+-- set and return valid yaw
+local set_yaw = function(self, yaw, delay, dtime)
+
+	if not yaw or yaw ~= yaw then
+		yaw = 0
+	end
+
+	delay = delay or 0
+
+	if delay == 0 then
+		if self.shaking and dtime then
+			yaw = yaw + (math_random() * 2 - 1) * 5 * dtime
+		end
+		self.yaw(yaw)
+		update_roll(self)
+		return yaw
+	end
+
+	self.target_yaw = yaw
+	self.delay = delay
+
+	return self.target_yaw
+end
+
+
+-- global function to set mob yaw
+function mobs:yaw(self, yaw, delay, dtime)
+	set_yaw(self, yaw, delay, dtime)
+end