diff --git a/.github/workflows/selene.yml b/.github/workflows/selene.yml
new file mode 100644
index 00000000..d9198149
--- /dev/null
+++ b/.github/workflows/selene.yml
@@ -0,0 +1,22 @@
+name: Selene check
+
+on:
+  push:
+    branches:
+      - "main"
+    paths:
+      - "lua/**/*.lua"
+      - "plugin/*.lua"
+  pull_request:
+
+jobs:
+  selene:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Run Selene check
+        uses: NTBBloodbath/selene-action@v1.0.0
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          args: lua/
+          version: 0.28.0
diff --git a/Makefile b/Makefile
index 1daeeecb..53babd00 100644
--- a/Makefile
+++ b/Makefile
@@ -19,3 +19,8 @@ coverage:
 	pdm run coverage run -m pytest; \
 	pdm run coverage html; \
 	pdm run coverage report -m
+
+lint:
+	pdm run ruff check src/**/*.py; \
+	pdm run basedpyright src/**/*.py; \
+	selene lua/**/*.lua plugin/*.lua
diff --git a/docs/CONTRIBUTING.md b/docs/CONTRIBUTING.md
index 7a7c4939..cabbb293 100644
--- a/docs/CONTRIBUTING.md
+++ b/docs/CONTRIBUTING.md
@@ -22,7 +22,8 @@ them locally before you open the PR.
 
 This project also runs static analysis with
 [basedpyright](https://docs.basedpyright.com). GitHub Action will also run the
-check when a PR is submitted.
+check when a PR is submitted. This, as well as `ruff check`, are both included
+in `make lint`.
 
 You may also find it helpful to 
 [enable logging](https://github.com/Davidyz/VectorCode/blob/main/docs/cli.md#debugging-and-diagnosing) 
@@ -35,6 +36,9 @@ formatted (stylua) and appropriately type-annotated, you're good. I do have
 plans to write some tests, but before that happens, formatting and type 
 annotations are the only things that you need to take special care of.
 
+The lua codebase is linted by [selene](https://github.com/Kampfkarren/selene).
+You may run `make lint` or call `selene` from the CLI to lint the code.
+
 You may find it useful to 
 [enable logging](https://github.com/Davidyz/VectorCode/blob/main/docs/cli.md#debugging-and-diagnosing) 
 when you're poking around the codebase.
diff --git a/lua/vectorcode/cacher/default.lua b/lua/vectorcode/cacher/default.lua
index 0788dcc4..2b5d9850 100644
--- a/lua/vectorcode/cacher/default.lua
+++ b/lua/vectorcode/cacher/default.lua
@@ -77,7 +77,7 @@ local function async_runner(query_message, buf_nr)
       end
       logger.debug("vectorcode ", buf_name, " default cacher results: ", json_result)
       CACHE[buf_nr].job_count = CACHE[buf_nr].job_count - 1
-      assert(job_pid ~= nil)
+      assert(job_pid ~= nil, "Failed to fetch the job pid.")
       CACHE[buf_nr].jobs[job_pid] = nil
 
       if exit_code ~= 0 then
@@ -189,7 +189,7 @@ M.register_buffer = vc_config.check_cli_wrap(
           or (vim.uv.clock_gettime("realtime").sec - cache.last_run) > opts.debounce
         then
           local cb = cache.options.query_cb
-          assert(type(cb) == "function")
+          assert(type(cb) == "function", "`cb` should be a function.")
           async_runner(cb(bufnr), bufnr)
         end
       end,
@@ -249,7 +249,7 @@ M.buf_is_registered = function(bufnr)
   if bufnr == 0 or bufnr == nil then
     bufnr = vim.api.nvim_get_current_buf()
   end
-  return type(CACHE[bufnr]) == "table" and CACHE[bufnr] ~= {}
+  return type(CACHE[bufnr]) == "table" and not vim.tbl_isempty(CACHE[bufnr])
 end
 
 M.query_from_cache = vc_config.check_cli_wrap(
diff --git a/lua/vectorcode/cacher/lsp.lua b/lua/vectorcode/cacher/lsp.lua
index bc5bcca5..df9abe68 100644
--- a/lua/vectorcode/cacher/lsp.lua
+++ b/lua/vectorcode/cacher/lsp.lua
@@ -23,7 +23,7 @@ local client_id = nil
 ---@param project_root string
 ---@return string?
 local function check_project_root(bufnr, project_root)
-  assert(bufnr ~= 0)
+  assert(bufnr ~= 0, "Need a non-zero bufnr")
   if project_root == nil then
     local cwd = vim.uv.cwd() or "."
     local result = vim.fs.root(cwd, ".vectorcode") or vim.fs.root(cwd, ".git")
@@ -76,7 +76,7 @@ local function kill_jobs(bufnr)
   if client == nil then
     return
   end
-  for request_id, time in pairs(CACHE[bufnr].jobs) do
+  for request_id, _ in pairs(CACHE[bufnr].jobs) do
     job_runner.stop_job(request_id)
   end
   cleanup_lsp_requests()
@@ -93,7 +93,7 @@ local function async_runner(query_message, buf_nr)
     buf_name = vim.api.nvim_buf_get_name(buf_nr)
     logger.debug("Started lsp cacher job on :", buf_name)
   end)
-  assert(client_id ~= nil)
+  assert(client_id ~= nil, "LSP client hasn't been initialised.")
   ---@type VectorCode.Cache
   local cache = CACHE[buf_nr]
   local args = {
diff --git a/lua/vectorcode/config.lua b/lua/vectorcode/config.lua
index 9fcc84f5..c447d97c 100644
--- a/lua/vectorcode/config.lua
+++ b/lua/vectorcode/config.lua
@@ -130,7 +130,7 @@ return {
       logger.info("Received setup opts:\n", opts)
       opts = opts or {}
       setup_config = vim.tbl_deep_extend("force", config, opts or {})
-      for k, v in pairs(setup_config.async_opts) do
+      for k, _ in pairs(setup_config.async_opts) do
         if
           setup_config[k] ~= nil
           and (opts.async_opts == nil or opts.async_opts[k] == nil)
diff --git a/lua/vectorcode/init.lua b/lua/vectorcode/init.lua
index d0bbf350..a92d88e1 100644
--- a/lua/vectorcode/init.lua
+++ b/lua/vectorcode/init.lua
@@ -79,14 +79,15 @@ M.vectorise = vc_config.check_cli_wrap(
   function(files, project_root)
     logger.info("vectorcode.vectorise: ", files, project_root)
     local args = { "--pipe", "vectorise" }
-    if project_root ~= nil then
-      vim.list_extend(args, { "--project_root", project_root })
-    elseif
-      M.check("config", function(obj)
-        if obj.code == 0 then
-          project_root = obj.stdout
-        end
-      end)
+    if
+      project_root ~= nil
+      or (
+        M.check("config", function(obj)
+          if obj.code == 0 then
+            project_root = obj.stdout
+          end
+        end)
+      )
     then
       vim.list_extend(args, { "--project_root", project_root })
     end
@@ -203,7 +204,7 @@ end
 ---@return string[]
 M.prompts = vc_config.check_cli_wrap(function()
   local result, error = jobrunner.run({ "prompts", "-p" }, -1, 0)
-  if result == nil or result == {} then
+  if result == nil or vim.tbl_isempty(result) then
     logger.warn(vim.inspect(error))
     if vc_config.get_user_config().notify then
       notify(vim.inspect(error))
diff --git a/lua/vectorcode/integrations/codecompanion/func_calling_tool.lua b/lua/vectorcode/integrations/codecompanion/func_calling_tool.lua
index cce8a57a..14d6e313 100644
--- a/lua/vectorcode/integrations/codecompanion/func_calling_tool.lua
+++ b/lua/vectorcode/integrations/codecompanion/func_calling_tool.lua
@@ -37,12 +37,11 @@ return check_cli_wrap(function(opts)
     cmds = {
       ---@param agent CodeCompanion.Agent
       ---@param action table
-      ---@param input table
       ---@return nil|{ status: string, msg: string }
-      function(agent, action, input, cb)
+      function(agent, action, _, cb)
         logger.info("CodeCompanion tool called with the following arguments:\n", action)
         job_runner = cc_common.initialise_runner(opts.use_lsp)
-        assert(job_runner ~= nil)
+        assert(job_runner ~= nil, "Jobrunner not initialised!")
         assert(
           type(cb) == "function",
           "Please upgrade CodeCompanion.nvim to at least 13.5.0"
diff --git a/lua/vectorcode/integrations/copilotchat.lua b/lua/vectorcode/integrations/copilotchat.lua
index 0f470bf2..5be57abb 100644
--- a/lua/vectorcode/integrations/copilotchat.lua
+++ b/lua/vectorcode/integrations/copilotchat.lua
@@ -37,7 +37,7 @@ end
 ---@async
 local run_job = async.wrap(function(args, use_lsp, bufnr, callback)
   local runner = get_runner(use_lsp)
-  assert(runner ~= nil)
+  assert(runner ~= nil, "Failed to initialize the runner!")
   runner.run_async(args, callback, bufnr)
 end, 4)
 
diff --git a/lua/vectorcode/jobrunner/lsp.lua b/lua/vectorcode/jobrunner/lsp.lua
index 14e100b3..69d165a6 100644
--- a/lua/vectorcode/jobrunner/lsp.lua
+++ b/lua/vectorcode/jobrunner/lsp.lua
@@ -39,17 +39,17 @@ end
 
 function jobrunner.run(args, timeout_ms, bufnr)
   jobrunner.init(false)
-  assert(CLIENT ~= nil)
-  assert(bufnr ~= nil)
+  assert(CLIENT ~= nil, "Failed to initialize the LSP server!")
+  assert(bufnr ~= nil, "Need to pass the buffer number!")
   if timeout_ms == nil or timeout_ms < 0 then
     timeout_ms = 2 ^ 31 - 1
   end
   args = require("vectorcode.jobrunner").find_root(args, bufnr)
 
   local result, err, code
-  jobrunner.run_async(args, function(res, err, e_code)
+  jobrunner.run_async(args, function(res, e, e_code)
     result = res
-    err = err
+    err = e
     code = e_code
   end, bufnr)
   vim.wait(timeout_ms, function()
@@ -60,7 +60,7 @@ end
 
 function jobrunner.run_async(args, callback, bufnr)
   assert(jobrunner.init(false))
-  assert(bufnr ~= nil)
+  assert(bufnr ~= nil, "Need to pass the buffer number!")
   if not CLIENT.attached_buffers[bufnr] then
     if vim.lsp.buf_attach_client(bufnr, CLIENT.id) then
       local uri = vim.uri_from_bufnr(bufnr)
diff --git a/lua/vectorcode/types.lua b/lua/vectorcode/types.lua
index cea3c75b..55e7504d 100644
--- a/lua/vectorcode/types.lua
+++ b/lua/vectorcode/types.lua
@@ -14,10 +14,10 @@
 
 ---Type definitions for options accepted by `query` API.
 ---@class VectorCode.QueryOpts
----@field exclude_this boolean Whether to exclude the current buffer. Default: true
----@field n_query integer Number of results.
----@field notify boolean Notify on new results and other key moments.
----@field timeout_ms number Timeout (in milliseconds) for running a vectorcode command. Default: 5000
+---@field exclude_this boolean? Whether to exclude the current buffer. Default: true
+---@field n_query integer? Number of results.
+---@field notify boolean? Notify on new results and other key moments.
+---@field timeout_ms number? Timeout (in milliseconds) for running a vectorcode command. Default: 5000
 
 ---@class VectorCode.OnSetup Some actions that may be configured to run when `setup` is called.
 ---@field update boolean `vectorcode update`
diff --git a/lua/vectorcode/utils.lua b/lua/vectorcode/utils.lua
index 7ddea429..341c96cc 100644
--- a/lua/vectorcode/utils.lua
+++ b/lua/vectorcode/utils.lua
@@ -8,13 +8,13 @@ local function traverse(node, cb)
     traverse(node.result, cb)
   end
   if vim.isarray(node) then
-    for k, v in pairs(node) do
+    for _, v in pairs(node) do
       traverse(v, cb)
     end
     return
   end
   if vim.isarray(node.children) then
-    for k, v in pairs(node.children) do
+    for _, v in pairs(node.children) do
       traverse(v, cb)
     end
   end
@@ -47,7 +47,7 @@ function M.make_lsp_document_symbol_cb()
       return M.make_surrounding_lines_cb(-1)(bufnr)
     end
 
-    local result, err = vim.lsp.buf_request_sync(
+    local result, _ = vim.lsp.buf_request_sync(
       0,
       vim.lsp.protocol.Methods.textDocument_documentSymbol,
       { textDocument = vim.lsp.util.make_text_document_params(bufnr) }
diff --git a/neovim.toml b/neovim.toml
new file mode 100644
index 00000000..9544eea1
--- /dev/null
+++ b/neovim.toml
@@ -0,0 +1,6 @@
+[selene]
+base = "lua51"
+name = "neovim"
+
+[vim]
+any = true
diff --git a/plugin/vectorcode.lua b/plugin/vectorcode.lua
index 0d9d3ccc..ea54bb78 100644
--- a/plugin/vectorcode.lua
+++ b/plugin/vectorcode.lua
@@ -2,7 +2,7 @@ local vc_config = require("vectorcode.config")
 local notify_opts = vc_config.notify_opts
 
 ---@param args string[]?
----@return {string: any}
+---@return table<string, any>
 local function process_args(args)
   if args == nil then
     return {}
@@ -48,7 +48,7 @@ vim.api.nvim_create_user_command("VectorCode", function(args)
   end
 end, {
   nargs = 1,
-  complete = function(arglead, cmd, cursorpos)
+  complete = function(arglead, cmd, _)
     local cacher = vc_config.get_cacher_backend()
     local splitted_cmd = vim.tbl_filter(function(str)
       return str ~= nil and str ~= ""
diff --git a/selene.toml b/selene.toml
new file mode 100644
index 00000000..46a4d1eb
--- /dev/null
+++ b/selene.toml
@@ -0,0 +1,5 @@
+std = "neovim"
+exclude = ['lua/vectorcode/integrations/codecompanion/legacy_tool.lua']
+
+[rules]
+mixed_table = "allow"