diff --git a/digicode.lua b/digicode.lua
index 0d89183..174b9b7 100644
--- a/digicode.lua
+++ b/digicode.lua
@@ -2,6 +2,7 @@
 --------------
 -- Digicode --
 --------------
+local has_mesecons = minetest.get_modpath("mesecons")
 
 local secret_code = "1234"
 local allowed_chars = "0123456789"
@@ -122,7 +123,11 @@ minetest.register_node("scifi_nodes:digicode_on", {
 	light_source = 5,
 	groups = {cracky=1, oddly_breakable_by_hand=1, not_in_creative_inventory=1, mesecon_needs_receiver = 1},
 	drop = {items = {"scifi_nodes:digicode_off"}},
-	mesecons = {receptor = {state = mesecon.state.on,}},
+	mesecons = {
+		receptor = {
+			state = (has_mesecons and mesecon.state.on)
+		}
+	},
 	on_timer = toggle_digicode,
 	sounds = default.node_sound_glass_defaults(),
 })
@@ -140,7 +145,11 @@ minetest.register_node("scifi_nodes:digicode_off", {
 	paramtype = "light",
 	paramtype2 = "wallmounted",
 	groups = {cracky=1, oddly_breakable_by_hand=1, mesecon_needs_receiver = 1},
-	mesecons = {receptor = {state = mesecon.state.off,}},
+	mesecons = {
+		receptor = {
+			state = (has_mesecons and mesecon.state.off)
+		}
+	},
 	after_place_node = set_owner,
 	on_rightclick = show_digicode_formspec,
 	sounds = default.node_sound_glass_defaults(),
diff --git a/mod.conf b/mod.conf
index aa27b70..f05a2c8 100644
--- a/mod.conf
+++ b/mod.conf
@@ -1,4 +1,4 @@
 name = scifi_nodes
 description = Minetest mod that adds scifi themed blocks, doors, materials, plants and other assets.
-depends = default,dye,basic_materials, mesecons
-optional_depends = xpanes,moreblocks,mesecons_microcontroller,mesecons_button,mesecons_torch,mesecons_receiver
+depends = default,dye
+optional_depends = xpanes,mesecons,moreblocks,mesecons_microcontroller,mesecons_button,mesecons_torch,mesecons_receiver,basic_materials
diff --git a/palm_scanner.lua b/palm_scanner.lua
index da17cbc..5f07ea7 100644
--- a/palm_scanner.lua
+++ b/palm_scanner.lua
@@ -7,6 +7,8 @@
 -- re-use all the parameters in same order ! --
 -----------------------------------------------
 
+local has_mesecons = minetest.get_modpath("mesecons")
+
 -- after_place_node
 -- placer is a player object
 local function set_scanner_owner(pos, placer, itemstack, pointed_thing)
@@ -47,7 +49,7 @@ local function check_owner(pos, elapsed)
 	if clicker == owner then
 		minetest.sound_play("scifi_nodes_scanner_granted", {max_hear_distance = 8, pos = pos, gain = 1.0})
 		minetest.chat_send_player(clicker, "Access granted !")
-		toggle_palm_scanner (pos)
+		toggle_palm_scanner(pos)
 	else
 		minetest.chat_send_player(clicker, "Access refused !")
 		minetest.sound_play("scifi_nodes_scanner_refused", {max_hear_distance = 8, pos = pos, gain = 1.0})
@@ -69,9 +71,13 @@ minetest.register_node("scifi_nodes:palm_scanner_off", {
 	paramtype = "light",
 	paramtype2 = "wallmounted",
 	groups = {cracky=1, oddly_breakable_by_hand=1, mesecon_needs_receiver = 1},
-	mesecons = {receptor = {state = mesecon.state.off,}},
+	mesecons = {
+		receptor = {
+			state = (has_mesecons and mesecon.state.off)
+		}
+	},
 	after_place_node = set_scanner_owner,
-	on_rightclick = toggle_palm_scanner,
+	on_rightclick = (has_mesecons and toggle_palm_scanner),
 	sounds = default.node_sound_glass_defaults(),
 })
 
@@ -109,8 +115,12 @@ minetest.register_node("scifi_nodes:palm_scanner_on", {
 	light_source = 5,
 	groups = {cracky=1, oddly_breakable_by_hand=1, not_in_creative_inventory=1, mesecon_needs_receiver = 1},
 	drop = "scifi_nodes:palm_scanner_off",
-	mesecons = {receptor = {state = mesecon.state.on,}},
-	on_timer = toggle_palm_scanner,
+	mesecons = {
+		receptor = {
+			state = (has_mesecons and mesecon.state.on)
+		}
+	},
+	on_timer = (has_mesecons and toggle_palm_scanner),
 	sounds = default.node_sound_glass_defaults(),
 })
 
diff --git a/switches.lua b/switches.lua
index eb79053..a1bdef0 100644
--- a/switches.lua
+++ b/switches.lua
@@ -3,6 +3,8 @@
 -- Switches --
 --------------
 
+local has_mesecons = minetest.get_modpath("mesecons")
+
 local function toggle_switch(pos)
 	local node = minetest.get_node(pos)
 	local name = node.name
@@ -32,10 +34,14 @@ minetest.register_node("scifi_nodes:switch_on", {
 	paramtype2 = "wallmounted",
 	light_source = 5,
 	groups = {cracky=1, oddly_breakable_by_hand=1, not_in_creative_inventory=1, mesecon_needs_receiver = 1},
-	mesecons = {receptor = {state = mesecon.state.on,}},
+	mesecons = {
+		receptor = {
+			state = (has_mesecons and mesecon.state.on)
+		}
+	},
 	sounds = default.node_sound_glass_defaults(),
-	on_rightclick = toggle_switch,
-	on_timer = toggle_switch
+	on_rightclick = (has_mesecons and toggle_switch),
+	on_timer = (has_mesecons and toggle_switch)
 })
 
 minetest.register_node("scifi_nodes:switch_off", {
@@ -51,9 +57,13 @@ minetest.register_node("scifi_nodes:switch_off", {
 	paramtype = "light",
 	paramtype2 = "wallmounted",
 	groups = {cracky=1, oddly_breakable_by_hand=1, mesecon_needs_receiver = 1},
-	mesecons = {receptor = {state = mesecon.state.off,}},
+	mesecons = {
+		receptor = {
+			state = (has_mesecons and mesecon.state.off)
+		}
+	},
 	sounds = default.node_sound_glass_defaults(),
-	on_rightclick = toggle_switch
+	on_rightclick = (has_mesecons and toggle_switch)
 })
 
 minetest.register_craft({