diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 0204588..8f1be26 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -23,6 +23,26 @@ jobs:
       - name: Check formatting
         run: make fmt-check
 
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup Lua and LuaRocks
+        uses: leafo/gh-actions-lua@v11
+        with:
+          luaVersion: "5.1"
+
+      - name: Setup LuaRocks
+        uses: leafo/gh-actions-luarocks@v5
+
+      - name: Install luacheck
+        run: luarocks install luacheck
+
+      - name: Run lint
+        run: make lint
+
   test:
     name: Test
     runs-on: ubuntu-latest
diff --git a/.luacheckrc b/.luacheckrc
new file mode 100644
index 0000000..311dc9d
--- /dev/null
+++ b/.luacheckrc
@@ -0,0 +1,19 @@
+std = "lua51"
+
+globals = {
+  "vim",
+}
+
+files["tests/**/*.lua"] = {
+  globals = {
+    "vim",
+    "describe",
+    "it",
+    "before_each",
+    "after_each",
+    "setup",
+    "teardown",
+    "pending",
+    "assert",
+  },
+}
diff --git a/Makefile b/Makefile
index 3f2226a..f925c83 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-.PHONY: test test-file clean fmt fmt-check
+.PHONY: test test-file clean fmt fmt-check lint
 
 # Test runner
 PLENARY_DIR ?= /tmp/plenary.nvim
@@ -39,3 +39,7 @@ fmt:
 # Check Lua formatting
 fmt-check:
 	stylua --check lua plugin tests
+
+# Lint Lua files
+lint:
+	luacheck lua plugin tests
diff --git a/README.md b/README.md
index 94d8caf..8c3e587 100644
--- a/README.md
+++ b/README.md
@@ -231,6 +231,12 @@ make fmt
 make fmt-check
 ```
 
+* Run lint:
+
+```sh
+make lint
+```
+
 * Run tests:
 
 ```sh
diff --git a/lua/comment-translate/commands.lua b/lua/comment-translate/commands.lua
index 4e51aee..f98f6fc 100644
--- a/lua/comment-translate/commands.lua
+++ b/lua/comment-translate/commands.lua
@@ -181,7 +181,7 @@ end
 local function disable_all_buffers()
   ui.virtual_text.clear_all()
 
-  for buf, state in pairs(immersive_state) do
+  for _, state in pairs(immersive_state) do
     state.enabled = false
     bump_token(state)
   end
diff --git a/tests/integration_spec.lua b/tests/integration_spec.lua
index c091f3d..26f9d09 100644
--- a/tests/integration_spec.lua
+++ b/tests/integration_spec.lua
@@ -291,7 +291,6 @@ describe('integration', function()
 
   describe('manual hover mode', function()
     local config
-    local commands
 
     before_each(function()
       for name, _ in pairs(package.loaded) do
@@ -312,7 +311,7 @@ describe('integration', function()
         },
       })
 
-      commands = require('comment-translate.commands')
+      require('comment-translate.commands')
     end)
 
     it('should have auto hover disabled in config', function()
diff --git a/tests/llm_spec.lua b/tests/llm_spec.lua
index 8d7f898..e22f408 100644
--- a/tests/llm_spec.lua
+++ b/tests/llm_spec.lua
@@ -33,7 +33,7 @@ describe('translate.llm', function()
     }
 
     local FakeJob = {}
-    function FakeJob:new(opts)
+    function FakeJob.new(_, opts)
       job_state.new_calls = job_state.new_calls + 1
       job_state.last_opts = opts
       return setmetatable({
@@ -43,11 +43,11 @@ describe('translate.llm', function()
           result = function()
             return { job_state.stdout }
           end,
-          start = function(self)
+          start = function(job)
             for _, line in ipairs(job_state.stderr_lines or {}) do
-              self._opts.on_stderr(nil, line)
+              job._opts.on_stderr(nil, line)
             end
-            self._opts.on_exit(self, job_state.exit_code)
+            job._opts.on_exit(job, job_state.exit_code)
           end,
         },
       })
diff --git a/tests/minimal_init.lua b/tests/minimal_init.lua
index dc2114a..5018f00 100644
--- a/tests/minimal_init.lua
+++ b/tests/minimal_init.lua
@@ -1,5 +1,7 @@
 ---Minimal init for running tests
----Usage: nvim --headless -u tests/minimal_init.lua -c "PlenaryBustedDirectory tests/ {minimal_init = 'tests/minimal_init.lua'}"
+---Usage:
+---nvim --headless -u tests/minimal_init.lua
+---Then run PlenaryBustedDirectory with this minimal_init.
 
 local plenary_dir = os.getenv('PLENARY_DIR') or '/tmp/plenary.nvim'
 local is_not_a_directory = vim.fn.isdirectory(plenary_dir) == 0