diff --git a/mods/mapgen/init.lua b/mods/mapgen/init.lua
index 4992c89..c326ffc 100644
--- a/mods/mapgen/init.lua
+++ b/mods/mapgen/init.lua
@@ -1,16 +1,16 @@
 
-local mgparams = minetest.get_mapgen_params()
+local mgparams = core.get_mapgen_params()
 if mgparams.mgname == "v6" then
 	error("Mapgen 'v6' is not supported by Cave Game.", 0)
 end
 
-minetest.register_alias("mapgen_stone", "minecraft:stone")
-minetest.register_alias("mapgen_water_source", "air")
-minetest.register_alias("mapgen_river_water_source", "air")
+core.register_alias("mapgen_stone", "minecraft:stone")
+core.register_alias("mapgen_water_source", "air")
+core.register_alias("mapgen_river_water_source", "air")
 
 
 -- FIXME: Why dosen't node_top work properly?
-minetest.register_biome({
+core.register_biome({
 	name = "cavegame",
 	node_dust = "minecraft:grass",
 --	node_top = "minecraft:grass",
@@ -23,13 +23,13 @@ minetest.register_biome({
 
 
 if mgparams.mgname == "singlenode" then
-	local ground_level = tonumber(minetest.settings:get("water_level") or 1)
-	local air = minetest.get_content_id("air")
-	local stone = minetest.get_content_id("minecraft:stone")
-	local grass = minetest.get_content_id("minecraft:grass")
+	local ground_level = tonumber(core.settings:get("water_level") or 1)
+	local air = core.get_content_id("air")
+	local stone = core.get_content_id("minecraft:stone")
+	local grass = core.get_content_id("minecraft:grass")
 	
-	minetest.register_on_generated(function(minp, maxp, blockseed)
-		local vm, emin, emax = minetest.get_mapgen_object("voxelmanip")
+	core.register_on_generated(function(minp, maxp, blockseed)
+		local vm, emin, emax = core.get_mapgen_object("voxelmanip")
 		local va = VoxelArea:new({MinEdge=emin, MaxEdge=emax})
 		
 		local nodes = vm:get_data()
@@ -50,14 +50,14 @@ if mgparams.mgname == "singlenode" then
 	end)
 	
 	-- see https://github.com/minetest/minetest/issues/12782
-	if not minetest.settings:get("static_spawnpoint") then
+	if not core.settings:get("static_spawnpoint") then
 		local spawnpos = vector.new(0, ground_level+1, 0)
-		minetest.register_on_joinplayer(function(player, lastlogin)
+		core.register_on_joinplayer(function(player, lastlogin)
 			if not lastlogin then
 				player:set_pos(spawnpos)
 			end
 		end)
-		minetest.register_on_respawnplayer(function(player)
+		core.register_on_respawnplayer(function(player)
 			player:set_pos(spawnpos)
 			return true
 		end)
diff --git a/mods/nodes/init.lua b/mods/nodes/init.lua
index a3c7133..d41baa6 100644
--- a/mods/nodes/init.lua
+++ b/mods/nodes/init.lua
@@ -1,8 +1,8 @@
 
-minetest.register_on_mods_loaded(function()
-	for name,def in pairs(minetest.registered_nodes) do
+core.register_on_mods_loaded(function()
+	for name,def in pairs(core.registered_nodes) do
 		if def.order then
-			minetest.register_alias(tostring(def.order), name)
+			core.register_alias(tostring(def.order), name)
 		end
 	end
 end)
@@ -11,7 +11,7 @@ end)
 
  -- nodes --
 
-minetest.register_node(":minecraft:stone", {
+core.register_node(":minecraft:stone", {
 	order = 1,
 	description = "Stone",
 	tiles = { "default_cobble.png" },
@@ -19,7 +19,7 @@ minetest.register_node(":minecraft:stone", {
 	is_ground_content = true,
 })
 
-minetest.register_node(":minecraft:grass", {
+core.register_node(":minecraft:grass", {
 	order = 2,
 	description = "Grass",
 	tiles = { "default_grass.png" },
diff --git a/mods/player/init.lua b/mods/player/init.lua
index 8223236..4234263 100644
--- a/mods/player/init.lua
+++ b/mods/player/init.lua
@@ -13,14 +13,14 @@ local hud_flags = {
 local inv_list = {}
 local inv_size = 0
 
-minetest.register_on_mods_loaded(function()
+core.register_on_mods_loaded(function()
 	local unordered = {}
-	for name,def in pairs(minetest.registered_nodes) do
+	for name,def in pairs(core.registered_nodes) do
 		if def.order then
 			inv_size = math.max(inv_size, def.order)
 			inv_list[def.order] = name
 			
-			minetest.override_item(name, {
+			core.override_item(name, {
 			--	drop = "",
 			--	stack_max = 1,
 				range = 16,
@@ -37,7 +37,7 @@ minetest.register_on_mods_loaded(function()
 	end
 end)
 
-minetest.register_on_joinplayer(function(player, last_login)
+core.register_on_joinplayer(function(player, last_login)
 --	player:set_sky({}) --TODO
 	player:set_sun({ visible=false, sunrise_visible=false })
 	player:set_moon({ visible=false })
@@ -53,7 +53,7 @@ minetest.register_on_joinplayer(function(player, last_login)
 	player:hud_set_hotbar_itemcount(inv_size)
 	
 	local name = player:get_player_name()
-	local inv = minetest.get_inventory({ type="player", name=name })
+	local inv = core.get_inventory({ type="player", name=name })
 	inv:set_size("main", inv_size)
 	inv:set_list("main", inv_list)
 	
@@ -78,7 +78,7 @@ for _,group in ipairs(groups) do
 	groupcaps[group] = cap
 end
 
-minetest.register_item(":", {
+core.register_item(":", {
 	type = "none",
 	tool_capabilities = {
 		full_punch_interval = 0.2,
@@ -92,13 +92,13 @@ minetest.register_item(":", {
 
  -- in-world items --
 
---local old_item_drop = minetest.item_drop
-minetest.item_drop = function(itemstack, ...)
+--local old_item_drop = core.item_drop
+core.item_drop = function(itemstack, ...)
 	return itemstack
 end
 
-local old_item_place = minetest.item_place
-minetest.item_place = function(...)
+local old_item_place = core.item_place
+core.item_place = function(...)
 	old_item_place(...)
 	return nil
 end