diff --git a/.github/workflows/luacheck.yml b/.github/workflows/luacheck.yml
index 5290e245..3c99a991 100644
--- a/.github/workflows/luacheck.yml
+++ b/.github/workflows/luacheck.yml
@@ -1,11 +1,10 @@
-on: [push, pull_request]
 name: luacheck
+on: [push, pull_request]
 jobs:
-  lint:
+  luacheck:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@master
-      - name: lint
-        uses: Roang-zero1/factorio-mod-luacheck@master
-        with:
-          luacheckrc_url: ""
+      - name: Checkout
+        uses: actions/checkout@master
+      - name: Luacheck
+        uses: lunarmodules/luacheck@master
diff --git a/.github/workflows/mineunit.yml b/.github/workflows/mineunit.yml
index f047d379..b1a1b449 100644
--- a/.github/workflows/mineunit.yml
+++ b/.github/workflows/mineunit.yml
@@ -3,22 +3,21 @@ name: mineunit
 on: [push, pull_request]
 
 jobs:
-  build:
+  mineunit:
 
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v2
-      with:
-        submodules: true
+    - uses: actions/checkout@v3
 
     - id: mineunit
       uses: mt-mods/mineunit-actions@master
       with:
         working-directory: ./technic
+        mineunit-args: --engine-version 5.4.1
         badge-label: Test coverage
 
-    - uses: RubbaBoy/BYOB@v1.2.0
+    - uses: RubbaBoy/BYOB@v1.3.0
       if: success() && github.event_name == 'push' && github.ref == 'refs/heads/master'
       with:
         NAME: "${{ steps.mineunit.outputs.badge-name }}"
@@ -40,6 +39,7 @@ jobs:
           --------------------------------------------------------------
           ${{ steps.mineunit.outputs.mineunit-report }}
           ```
+          
           ### Raw test runner output for geeks:
           ```
           ${{ steps.mineunit.outputs.mineunit-stdout }}
@@ -53,7 +53,7 @@ jobs:
         comment: |
           <details><summary><i>Mineunit failed regression tests, click for details</i></summary>
           
-          ### Regression test log for technic:
+          ### Regression test log for Technic:
           ```
           ${{ steps.mineunit.outputs.mineunit-stdout }}
           ```
diff --git a/technic/spec/fixtures/default.lua b/technic/spec/fixtures/default.lua
new file mode 100644
index 00000000..35532a00
--- /dev/null
+++ b/technic/spec/fixtures/default.lua
@@ -0,0 +1,32 @@
+mineunit:set_modpath("default", "spec/fixtures")
+
+local function register_node(name, groups, additional_definition)
+	local definition = {
+		description = name.." description",
+		tiles = { "default_"..name },
+		groups = groups,
+	}
+	for k,v in pairs(additional_definition or {}) do definition[k] = v end
+	minetest.register_node(":default:"..name, definition)
+end
+
+local function register_item(name)
+	minetest.register_craftitem(":default:"..name, {
+		description = name.." description",
+	})
+end
+
+-- Register some basic nodes for cutting, grinding, digging, registering recipes etc.
+register_node("stone", {cracky = 3, stone = 1}, {is_ground_content = true, drop = "default:cobble"})
+register_node("cobble", {cracky=3, stone = 2})
+register_node("sand", {snappy=2, choppy=2, oddly_breakable_by_hand=2})
+register_node("wood", {tree=1, choppy=2, oddly_breakable_by_hand=2})
+register_node("dirt", {crumbly = 3, soil = 1})
+register_node("sandstone", {crumbly = 1, cracky = 3})
+register_node("steelblock", {cracky = 1, level = 2})
+register_node("furnace", {cracky=2})
+register_node("furnace_active", {cracky=2, not_in_creative_inventory=1}, {drop = "default:furnace"})
+
+register_item("steel_ingot")
+
+screwdriver = {}
\ No newline at end of file
diff --git a/technic/spec/fixtures/digilines.lua b/technic/spec/fixtures/digilines.lua
new file mode 100644
index 00000000..ad3a2c2b
--- /dev/null
+++ b/technic/spec/fixtures/digilines.lua
@@ -0,0 +1,36 @@
+-- Simple digilines mod fixture that logs sent messages, works with some simple digiline mods
+
+mineunit:set_modpath("digilines", "spec/fixtures")
+
+digilines = {
+	_msg_log = {},
+	receptor_send = function(pos, rules, channel, msg)
+		table.insert(digilines._msg_log, {
+			pos = pos,
+			rules = rules,
+			channel = channel,
+			msg = msg,
+		})
+	end,
+	rules = {
+		default = {
+			{x=0,  y=0,  z=-1},
+			{x=1,  y=0,  z=0},
+			{x=-1, y=0,  z=0},
+			{x=0,  y=0,  z=1},
+			{x=1,  y=1,  z=0},
+			{x=1,  y=-1, z=0},
+			{x=-1, y=1,  z=0},
+			{x=-1, y=-1, z=0},
+			{x=0,  y=1,  z=1},
+			{x=0,  y=-1, z=1},
+			{x=0,  y=1,  z=-1},
+			{x=0,  y=-1, z=-1}
+		}
+	}
+}
+
+digilines = setmetatable(digilines, {
+	__call = function(self,...) return self end,
+	__index = function(...) return function(...)end end,
+})
diff --git a/technic/spec/fixtures/mesecons.lua b/technic/spec/fixtures/mesecons.lua
new file mode 100644
index 00000000..1b2abf6e
--- /dev/null
+++ b/technic/spec/fixtures/mesecons.lua
@@ -0,0 +1,27 @@
+mineunit:set_modpath("mesecons", "spec/fixtures")
+mineunit:set_modpath("mesecons_mvps", "spec/fixtures")
+
+mesecon = {
+	state = {},
+	rules = {
+		default = {
+			{x =  0, y =  0, z = -1},
+			{x =  1, y =  0, z =  0},
+			{x = -1, y =  0, z =  0},
+			{x =  0, y =  0, z =  1},
+			{x =  1, y =  1, z =  0},
+			{x =  1, y = -1, z =  0},
+			{x = -1, y =  1, z =  0},
+			{x = -1, y = -1, z =  0},
+			{x =  0, y =  1, z =  1},
+			{x =  0, y = -1, z =  1},
+			{x =  0, y =  1, z = -1},
+			{x =  0, y = -1, z = -1},
+		}
+	}
+}
+
+mesecon = setmetatable(mesecon, {
+	__call = function(self,...) return self end,
+	__index = function(...) return function(...)end end,
+})
diff --git a/technic/spec/fixtures/mineunit.conf b/technic/spec/fixtures/mineunit.conf
deleted file mode 100644
index e69de29b..00000000
diff --git a/technic/spec/fixtures/technic.conf b/technic/spec/fixtures/technic.conf
new file mode 100644
index 00000000..f17e5da4
--- /dev/null
+++ b/technic/spec/fixtures/technic.conf
@@ -0,0 +1,27 @@
+enable_cans = true
+enable_chainsaw = true
+enable_flashlight = true
+enable_mining_drill = true
+enable_mining_laser = true
+enable_multimeter = true
+enable_prospector = true
+enable_sonic_screwdriver = true
+enable_tree_tap = true
+enable_vacuum = true
+
+multimeter_remote_start_ttl = 300
+
+enable_wind_mill = true
+enable_nuclear_reactor_digiline_selfdestruct = true
+quarry_max_depth = 100
+quarry_time_limit = 5000
+
+switch_off_delay_seconds = 1800
+network_overload_reset_time = 20
+admin_priv = basic_privs
+enable_corium_griefing = true
+enable_radiation_protection = true
+enable_radiation_throttling = true
+enable_entity_radiation_damage = true
+enable_longterm_radiation_damage = true
+max_lag_reduction_multiplier = 0.99
\ No newline at end of file
diff --git a/technic/spec/fixtures/technic.lua b/technic/spec/fixtures/technic.lua
new file mode 100644
index 00000000..ad9e86b4
--- /dev/null
+++ b/technic/spec/fixtures/technic.lua
@@ -0,0 +1,22 @@
+-- Use this fixture when loading full Technic mod.
+-- Loads all required modules and fixtures for technic
+
+-- Load modules required by tests
+mineunit("core")
+mineunit("player")
+mineunit("protection")
+mineunit("common/after")
+mineunit("server")
+mineunit("voxelmanip")
+if mineunit:config("engine_version") ~= "mineunit" then
+	mineunit("game/voxelarea")
+end
+
+-- Load fixtures required by tests
+fixture("default")
+fixture("mesecons")
+fixture("digilines")
+fixture("pipeworks")
+
+-- Load technic_worldgen
+fixture("technic_worldgen")
diff --git a/technic/spec/fixtures/technic_worldgen.lua b/technic/spec/fixtures/technic_worldgen.lua
new file mode 100644
index 00000000..13b3e986
--- /dev/null
+++ b/technic/spec/fixtures/technic_worldgen.lua
@@ -0,0 +1,7 @@
+-- Load technic_worldgen mod
+
+mineunit:set_modpath("technic_worldgen", "../technic_worldgen")
+
+mineunit:set_current_modname("technic_worldgen")
+sourcefile("../technic_worldgen/init")
+mineunit:restore_current_modname()
diff --git a/technic/spec/mineunit.conf b/technic/spec/mineunit.conf
index e69de29b..e67077f5 100644
--- a/technic/spec/mineunit.conf
+++ b/technic/spec/mineunit.conf
@@ -0,0 +1,11 @@
+deprecated = "ignore"
+time_step = 100
+exclude = {
+	-- Integration tests are not part of mod code
+	"integration_test",
+	-- These are commented out, not part of mod without manually editing code
+	"machines/MV/lighting",
+	"machines/MV/power_radiator",
+	-- Exclude everything outside of technic directory, some are tested but we do not want stats for these
+	"^../"
+}
\ No newline at end of file
diff --git a/technic/spec/tools_spec.lua b/technic/spec/tools_spec.lua
new file mode 100644
index 00000000..1d0a9f86
--- /dev/null
+++ b/technic/spec/tools_spec.lua
@@ -0,0 +1,168 @@
+require("mineunit")
+--[[
+	Technic tool regression tests.
+	Execute mineunit at technic source directory.
+--]]
+
+-- Load complete technic mod
+fixture("technic")
+sourcefile("init")
+
+describe("Technic power tool", function()
+
+	world.set_default_node("air")
+
+	-- HV battery box and some HV solar arrays for charging
+	local BB_Charge_POS = {x=0,y=51,z=0}
+	local BB_Discharge_POS = {x=0,y=51,z=2}
+	world.layout({
+		-- Network with generators for charging tools in battery box
+		{BB_Charge_POS, "technic:hv_battery_box0"},
+		{{x=1,y=51,z=0}, "technic:switching_station"},
+		{{{x=2,y=51,z=0},{x=10,y=51,z=0}}, "technic:solar_array_hv"},
+		{{{x=0,y=50,z=0},{x=10,y=50,z=0}}, "technic:hv_cable"},
+		-- Network without generators for discharging tools in battery box
+		{BB_Discharge_POS, "technic:hv_battery_box0"},
+		{{x=1,y=51,z=2}, "technic:switching_station"},
+		{{{x=0,y=50,z=2},{x=1,y=50,z=2}}, "technic:hv_cable"},
+	})
+
+	-- Some helpers to make stack access simpler
+	local player = Player("SX")
+	local charge_inv = minetest.get_meta(BB_Charge_POS):get_inventory()
+	local discharge_inv = minetest.get_meta(BB_Discharge_POS):get_inventory()
+	local function set_charge_stack(stack) charge_inv:set_stack("src", 1, stack) end
+	local function get_charge_stack() return charge_inv:get_stack("src", 1) end
+	local function set_discharge_stack(stack) discharge_inv:set_stack("dst", 1, stack) end
+	local function get_discharge_stack() return discharge_inv:get_stack("dst", 1) end
+	local function set_player_stack(stack) return player:get_inventory():set_stack("main", 1, stack) end
+	local function get_player_stack() return player:get_inventory():get_stack("main", 1) end
+
+	-- Execute on mods loaded callbacks to finish loading.
+	mineunit:mods_loaded()
+	-- Tell mods that 1 minute passed already to execute all weird minetest.after hacks.
+	mineunit:execute_globalstep(60)
+
+	describe("API", function()
+
+		setup(function()
+			set_charge_stack(ItemStack(nil))
+			set_discharge_stack(ItemStack(nil))
+			mineunit:set_current_modname("mymod")
+			mineunit:execute_on_joinplayer(player)
+		end)
+
+		teardown(function()
+			mineunit:execute_on_leaveplayer(player)
+			mineunit:restore_current_modname()
+		end)
+
+		local use_RE_charge_result
+
+		it("technic.register_power_tool works", function()
+			core.register_item("mymod:powertool", {
+				type = "tool",
+				description = "My Mod Power Tool",
+				inventory_image = "mymod_powertool.png",
+				wear_represents = "technic_RE_charge",
+				on_use = function(itemstack, player, pointed_thing)
+					use_RE_charge_result = technic.use_RE_charge(itemstack, 123)
+					return itemstack
+				end,
+			})
+			technic.power_tools["mymod:powertool"] = 1234
+			local itemdef = minetest.registered_items["mymod:powertool"]
+			assert.is_hashed(itemdef)
+		end)
+
+		it("technic.use_RE_charge works (zero charge)", function()
+			local stack = ItemStack("mymod:powertool")
+			local use_RE_charge_result = technic.use_RE_charge(stack, 123)
+			assert.equals("boolean", type(use_RE_charge_result))
+			assert.is_false(use_RE_charge_result)
+		end)
+
+		it("technic.get_RE_charge works (zero charge)", function()
+			local stack = ItemStack("mymod:powertool")
+			local charge, max_charge = technic.get_RE_charge(stack)
+			assert.equals(0, charge)
+			assert.equals(1234, max_charge)
+		end)
+
+		it("technic.set_RE_charge works (zero charge -> 123)", function()
+			local stack = ItemStack("mymod:powertool")
+			technic.set_RE_charge(stack, 123)
+			assert.equals(123, technic.get_RE_charge(stack))
+		end)
+
+		it("technic.use_RE_charge works (minimum charge)", function()
+			-- Add partially charged tool to player inventory
+			local stack = ItemStack("mymod:powertool")
+			technic.set_RE_charge(stack, 123)
+			set_player_stack(stack)
+
+			-- Use tool and verify results
+			spy.on(technic, "use_RE_charge")
+			player:do_use(player:get_pos())
+			assert.spy(technic.use_RE_charge).called(1)
+			assert.equals("boolean", type(use_RE_charge_result))
+			assert.is_true(use_RE_charge_result)
+			assert.equals(0, technic.get_RE_charge(get_player_stack()))
+		end)
+
+		it("technic.use_RE_charge works (minimum charge + 1)", function()
+			-- Add partially charged tool to player inventory
+			local stack = ItemStack("mymod:powertool")
+			technic.set_RE_charge(stack, 124)
+			set_player_stack(stack)
+			-- Use tool and verify results
+			player:do_use(player:get_pos())
+			assert.equals(1, technic.get_RE_charge(get_player_stack()))
+		end)
+
+	end)
+
+	describe("Flashlight", function()
+
+		local itemname = "technic:flashlight"
+		local itemdef = minetest.registered_items[itemname]
+
+		setup(function()
+			set_charge_stack(ItemStack(nil))
+			set_discharge_stack(ItemStack(nil))
+			mineunit:execute_on_joinplayer(player)
+		end)
+
+		teardown(function()
+			mineunit:execute_on_leaveplayer(player)
+		end)
+
+		it("is registered", function()
+			assert.is_hashed(itemdef)
+			assert.is_function(itemdef.on_refill)
+			assert.equals("technic_RE_charge", itemdef.wear_represents)
+			assert.is_number(technic.power_tools[itemname])
+			assert.gt(technic.power_tools[itemname], 0)
+		end)
+
+		it("charge is used", function()
+			-- Get fully charged item
+			local stack = ItemStack(itemname)
+			technic.set_RE_charge(stack, technic.power_tools[itemname])
+			set_player_stack(stack)
+
+			-- Use item, flashlight charge is used every globalstep and there's no on_use definition
+			for i=1, 100 do
+				mineunit:execute_globalstep(1)
+			end
+
+			-- Check that item charge was actually used and error is acceptable
+			local charge_used = technic.power_tools[itemname] - technic.get_RE_charge(get_player_stack())
+			local exact_use = 2 * 100 -- 2 per cycle / 100 cycles
+			assert.lt(0.9, charge_used / exact_use)
+			assert.gt(1.1, charge_used / exact_use)
+		end)
+
+	end)
+
+end)