diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
new file mode 100644
index 0000000..6b5ed17
--- /dev/null
+++ b/.github/workflows/lint.yml
@@ -0,0 +1,18 @@
+name: Lint
+
+on:
+  - push
+  - pull_request
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Run luacheck
+        uses: nebularg/actions-luacheck@v1
+        with:
+          annotate: warning
+          args: --no-color
diff --git a/.luacheckrc b/.luacheckrc
new file mode 100644
index 0000000..e219a54
--- /dev/null
+++ b/.luacheckrc
@@ -0,0 +1,63 @@
+std = 'lua51'
+
+quiet = 1 -- suppress report output for files without warnings
+
+-- see https://luacheck.readthedocs.io/en/stable/warnings.html#list-of-warnings
+-- and https://luacheck.readthedocs.io/en/stable/cli.html#patterns
+ignore = {
+	'212/self', -- unused argument self
+	'212/event', -- unused argument event
+	'212/unit', -- unused argument unit
+	'212/element', -- unused argument element
+	'312/event', -- unused value of argument event
+	'312/unit', -- unused value of argument unit
+	'431', -- shadowing an upvalue
+	'614', -- trailing whitespace in comment (we use this for docs)
+	'631', -- line is too long
+}
+
+globals = {
+	-- FrameXML objects we mutate
+	'SlashCmdList', -- FrameXML/ChatFrame.lua
+}
+
+read_globals = {
+	table = {fields = {'wipe'}},
+
+	-- FrameXML objects
+	'DEFAULT_CHAT_FRAME', -- FrameXML/ChatFrame.lua
+
+	-- FrameXML functions
+	'DisplayTableInspectorWindow', -- AddOns/Blizzard_DebugTools/Blizzard_TableInspector.lua
+	'UIParentLoadAddOn', -- FrameXML/UIParent.lua
+	'nop', -- FrameXML/UIParent.lua
+
+	-- SharedXML objects
+	'MinimalSliderWithSteppersMixin', -- SharedXML/Slider/MinimalSlider.lua
+	'Settings', -- SharedXML/Settings/Blizzard_Settings.lua
+	'SettingsPanel', -- SharedXML/Settings/Blizzard_SettingsPanel.xml
+
+	-- SharedXML functions
+	'DevTools_Dump', -- SharedXML/Dump.lua
+	'GenerateClosure', -- SharedXML/FunctionUtil.lua
+	'Mixin', -- SharedXML/Mixin.lua
+
+	-- namespaces
+	'C_AddOns',
+	'C_CVar',
+	'C_EventUtils',
+	'C_Map',
+	'C_UnitAuras',
+
+	-- API
+	'CombatLogGetCurrentEventInfo',
+	'CreateFrame',
+	'GetBuildInfo',
+	'GetLocale',
+	'InCombatLockdown',
+	'IsAddOnLoaded', -- until wrath classic bumps API
+	'UnitAuraSlots',
+	'UnitGUID',
+	'UnitIsOwnerOrControllerOfUnit',
+	'UnitIsUnit',
+}
diff --git a/modules/event.lua b/modules/event.lua
index 309b602..24dd48d 100644
--- a/modules/event.lua
+++ b/modules/event.lua
@@ -218,7 +218,7 @@ function eventMixin:IsUnitEventRegistered(event, ...)
 		assert(IsUnitEventValid(event, unit), 'event is not valid for the given unit')
 
 		if unitEventCallbacks[unit] and unitEventCallbacks[unit][event] then
-			for index, data in next, unitEventCallbacks[unit][event] do
+			for _, data in next, unitEventCallbacks[unit][event] do
 				if data.callback == callback then
 					return true
 				end
diff --git a/modules/settings/panel.lua b/modules/settings/panel.lua
index 0edee22..9c3964a 100644
--- a/modules/settings/panel.lua
+++ b/modules/settings/panel.lua
@@ -111,7 +111,7 @@ function addon:RegisterSettings(savedvariable, settings)
 		internalRegisterSettings(savedvariable, settings)
 	else
 		-- don't abuse OnLoad internally
-		addon:RegisterEvent('ADDON_LOADED', function(self, name)
+		addon:RegisterEvent('ADDON_LOADED', function(_, name)
 			if name == addonName then
 				internalRegisterSettings(savedvariable, settings)
 				return true -- unregister
diff --git a/modules/settings/savedvariables.lua b/modules/settings/savedvariables.lua
index a3723c9..8438428 100644
--- a/modules/settings/savedvariables.lua
+++ b/modules/settings/savedvariables.lua
@@ -1,4 +1,4 @@
-local addonName, addon = ...
+local _, addon = ...
 
 -- callback system that addons can use to detect when the player changes
 -- any setting, but also used internally to update the settings panel