nvim: fix startup errors, add language + project-run support

Startup errors:
- catppuccin: the bufferline integration moved to catppuccin.special.bufferline
- lspconfig-extended: drop the removed LazyVim keymaps API for
  opts.servers["*"].keys, and move remove-workspace-folder to <leader>clR
  so it stops colliding with LspRestart on <leader>clr
- options: lazyvim_cmp = "blink" is not a valid value, it is "blink.cmp"

Language support (python, c/cpp, rust, zephyr, and the common ones) via
lazyvim.json extras: dap.core, clangd, cmake, docker, git, json, rust,
toml, yaml.

- lang/zephyr.lua: gated entirely on ZEPHYR_BASE / ZEPHYR_SDK_INSTALL_DIR /
  GNUARMEMB_TOOLCHAIN_PATH, returning {} when none are set, so it is inert
  on machines without Zephyr. Nothing is hardcoded: the clangd
  --query-driver globs are built from those vars, falling back to resolving
  the cross-gcc through exepath()+fs_realpath(). Adds devicetree/kconfig
  treesitter and filetypes (*.overlay, Kconfig.*, prj.conf, *_defconfig).
- clangd/config.yaml: strip the GCC-only flags Zephyr emits into
  compile_commands.json (-fno-printf-return-value, -mfp16-format=*, ...),
  which clang rejects as "Unknown argument". Remove only drops flags that
  are present, so it is a no-op for native builds. Takes a built Zephyr app
  from 15 diagnostics to 0, with CONFIG_* resolving into the generated
  autoconf.h.
- npm-servers.lua: npm is not installed here, so yaml/docker servers failed
  to install on every startup and to spawn on every matching file. Sets
  both enabled = false and mason = false for servers whose binary is
  missing from PATH and from mason/bin.

Project runner under <leader>R (<leader>r is refactoring), dispatching on
the detected project type -- zephyr, rust, python, cmake, make:

  Rr run project   Rb build   Rt test   RF build+flash   Rf run file
  Rk configure     Rc clean   Rs select target/board     Ri info

Zephyr boards are picked with vim.ui.select over `west boards`, cached per
scan and persisted per project root under stdpath("state"), never written
into the project. A build with no board set prompts first, then proceeds.
Detection walks up from the last real file buffer, tracked by an autocmd,
because a terminal opened by one of these verbs would otherwise become the
buffer detection ran from.

Also <leader>b1..b9/b0 jump to buffer N (ordinal, no longer skipping the
current one) and <leader>b<Left>/<Right> cycle.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01StGBghPW9Dm7z7uj2VNWHr

nvim/lua/config/options.lua

@@ -8,7 +8,7 @@ vim.loader.enable()
 go.lualine_info_extras = false
 go.codeium_cmp_hide = false
 go.lazygit_config = false
-go.lazyvim_cmp = "blink"
+go.lazyvim_cmp = "blink.cmp"
 go.lazyvim_picker = "snacks"
 
 -- Define leader key

nvim/lua/plugins/extras/lang/zephyr.lua

@@ -0,0 +1,115 @@
+-- Zephyr RTOS support.
+--
+-- This extra is driven entirely by Zephyr's own environment variables and is
+-- inert unless one of them is set, so it costs nothing on a machine that does
+-- no Zephyr work and needs no per-host editing.
+--
+--   ZEPHYR_BASE               the zephyr repo -- presence of this enables the extra
+--   ZEPHYR_SDK_INSTALL_DIR    Zephyr SDK root (toolchain variant "zephyr")
+--   GNUARMEMB_TOOLCHAIN_PATH  toolchain root  (variant "gnuarmemb")
+--   ZEPHYR_TOOLCHAIN_VARIANT  which of the above is in use
+--
+-- Zephyr is otherwise "C + CMake + Kconfig + devicetree", so clangd and cmake
+-- do the heavy lifting. What clangd cannot work out unaided is the built-in
+-- include paths of a cross compiler, hence --query-driver.
+-- (Zephyr's build/compile_commands.json is found by clangd on its own: it
+-- searches ./ and ./build of each parent directory.)
+
+local zephyr_base = os.getenv("ZEPHYR_BASE")
+local sdk_dir     = os.getenv("ZEPHYR_SDK_INSTALL_DIR")
+local gnuarmemb   = os.getenv("GNUARMEMB_TOOLCHAIN_PATH")
+
+-- Not a Zephyr environment -> contribute nothing.
+if not (zephyr_base or sdk_dir or gnuarmemb) then
+  return {}
+end
+
+--- Toolchain globs for clangd's --query-driver, taken from the Zephyr vars.
+--- Falls back to whatever cross gcc the environment puts on $PATH when the
+--- toolchain variables are not set (as with a distro-packaged toolchain).
+---@return string[]
+local function query_driver_globs()
+  local globs, seen = {}, {}
+  local function add(p)
+    if p and p ~= "" and not seen[p] then
+      seen[p] = true
+      globs[#globs + 1] = p
+    end
+  end
+
+  -- Zephyr SDK: <sdk>/<target>-zephyr-elf/bin/<target>-zephyr-elf-gcc
+  if sdk_dir then
+    add(sdk_dir .. "/*/bin/*-gcc")
+  end
+
+  -- gnuarmemb variant: <root>/bin/arm-none-eabi-gcc
+  if gnuarmemb then
+    add(gnuarmemb .. "/bin/*-gcc")
+  end
+
+  -- No toolchain var set: resolve the cross compiler through $PATH instead of
+  -- assuming a prefix, and glob its real directory.
+  if #globs == 0 then
+    for _, cc in ipairs({
+      "arm-zephyr-eabi-gcc",
+      "arm-none-eabi-gcc",
+      "riscv64-zephyr-elf-gcc",
+      "xtensa-espressif_esp32-elf-gcc",
+    }) do
+      local exe = vim.fn.exepath(cc)
+      if exe ~= "" then
+        add(vim.fs.dirname(vim.uv.fs_realpath(exe) or exe) .. "/*-gcc")
+      end
+    end
+  end
+
+  return globs
+end
+
+return {
+  -- Syntax for the two Zephyr-specific languages
+  {
+    "nvim-treesitter/nvim-treesitter",
+    opts = { ensure_installed = { "devicetree", "kconfig" } },
+  },
+
+  {
+    "neovim/nvim-lspconfig",
+    -- Filetype detection Neovim does not ship with
+    init = function()
+      vim.filetype.add({
+        extension = {
+          overlay = "dts", -- board/shield overlays are devicetree
+        },
+        filename = {
+          ["prj.conf"] = "kconfig",
+          ["west.yml"] = "yaml",
+        },
+        pattern = {
+          ["Kconfig.*"] = "kconfig", -- Kconfig.foo, Kconfig.defconfig, ...
+          [".*/boards/.*%.conf"] = "kconfig",
+          [".*/prj_.*%.conf"] = "kconfig",
+          [".*_defconfig"] = "kconfig",
+        },
+      })
+    end,
+
+    opts = function(_, opts)
+      opts.servers = opts.servers or {}
+      local clangd = opts.servers.clangd or {}
+
+      local drivers = query_driver_globs()
+      if #drivers > 0 then
+        clangd.cmd = clangd.cmd or { "clangd" }
+        table.insert(clangd.cmd, "--query-driver=" .. table.concat(drivers, ","))
+      end
+
+      -- Treat a west workspace / Zephyr app as a project root.
+      clangd.root_markers = clangd.root_markers or {}
+      vim.list_extend(clangd.root_markers, { "west.yml", ".west", "prj.conf", "CMakeLists.txt" })
+
+      opts.servers.clangd = clangd
+      return opts
+    end,
+  },
+}

nvim/lua/plugins/extras/lsp/lspconfig-extended.lua

@@ -4,20 +4,6 @@ local prefix = "<leader>cl"
 return {
   {
     "neovim/nvim-lspconfig",
-    init = function()
-      local keys = require("lazyvim.plugins.lsp.keymaps").get()
-
-      keys[#keys + 1] = { "<leader>cl", false }
-      keys[#keys + 1] = { "<leader>cil", "<cmd>LspInfo<cr>", desc = "Lsp" }
-      keys[#keys + 1] = { prefix .. "r", "<cmd>LspRestart<cr>", desc = "Restart Lsp" }
-      keys[#keys + 1] = { prefix .. "s", "<cmd>LspStart<cr>", desc = "Start Lsp" }
-      keys[#keys + 1] = { prefix .. "S", "<cmd>LspStop<cr>", desc = "Stop Lsp" }
-
-      -- stylua: ignore start
-      keys[#keys + 1] = { prefix .. "r", function() vim.lsp.buf.remove_workspace_folder() end, desc = "Remove workspace" }
-      keys[#keys + 1] = { prefix .. "a", function() vim.lsp.buf.add_workspace_folder() end, desc = "Add workspace" }
-      -- stylua: ignore end
-    end,
     opts = {
       diagnostics = {
         virtual_text = {
@@ -42,6 +28,22 @@ return {
         enabled = false,
       },
       servers = {
+        -- Keymaps for every server. Was an `init` function calling
+        -- require("lazyvim.plugins.lsp.keymaps").get(), which LazyVim
+        -- deprecated in favour of the `keys` field on the server config.
+        ["*"] = {
+          keys = {
+            { "<leader>cl", false },
+            { "<leader>cil", "<cmd>LspInfo<cr>", desc = "Lsp" },
+            { prefix .. "r", "<cmd>LspRestart<cr>", desc = "Restart Lsp" },
+            { prefix .. "s", "<cmd>LspStart<cr>", desc = "Start Lsp" },
+            { prefix .. "S", "<cmd>LspStop<cr>", desc = "Stop Lsp" },
+            -- stylua: ignore start
+            { prefix .. "a", function() vim.lsp.buf.add_workspace_folder() end, desc = "Add workspace" },
+            { prefix .. "R", function() vim.lsp.buf.remove_workspace_folder() end, desc = "Remove workspace" },
+            -- stylua: ignore end
+          },
+        },
         lua_ls = {
           settings = {
             Lua = {

nvim/lua/plugins/extras/ui/bufferline-extended.lua

@@ -8,6 +8,21 @@ table.insert(keys, { prefix .. "s", "<Cmd>BufferLineSortByExtension<CR>", desc =
 
 table.insert(keys, { prefix .. "<", "<cmd>BufferLineMovePrev<cr>", desc = "Move buffer prev" })
 table.insert(keys, { prefix .. ">", "<cmd>BufferLineMoveNext<cr>", desc = "Move buffer next" })
+
+-- Jump straight to a buffer by its position in the bufferline.
+-- BufferLineGoToBuffer takes the absolute 1-based slot, so <leader>b1 is always
+-- the leftmost buffer and the count never skips the one you are already on.
+-- The ordinal shown in the bufferline (see numbers = "ordinal" below) is the
+-- number to press.
+for i = 1, 9 do
+  table.insert(keys, { prefix .. i, "<cmd>BufferLineGoToBuffer " .. i .. "<cr>", desc = "Buffer " .. i })
+end
+-- ...and 0 for the last one, however many there are.
+table.insert(keys, { prefix .. "0", "<cmd>BufferLineGoToBuffer -1<cr>", desc = "Last Buffer" })
+
+-- Arrows step through the bufferline in visible order.
+table.insert(keys, { prefix .. "<Left>",  "<cmd>BufferLineCyclePrev<cr>", desc = "Prev Buffer" })
+table.insert(keys, { prefix .. "<Right>", "<cmd>BufferLineCycleNext<cr>", desc = "Next Buffer" })
 -- stylua: ignore end
 
 return {
@@ -15,9 +30,11 @@ return {
   keys = keys,
   opts = {
     options = {
-      modified_icon = "",
+      modified_icon = "",
       color_icons = true,
       separator_style = "slope",
+      -- Show 1, 2, 3 ... so the number you see is the number you press.
+      numbers = "ordinal",
     },
   },
 }

nvim/lua/plugins/extras/ui/colorschemes/catppuccin.lua

@@ -50,7 +50,7 @@ return {
   {
     "akinsho/bufferline.nvim",
     opts = {
-      highlights = require("catppuccin.groups.integrations.bufferline").get_theme({
+      highlights = require("catppuccin.special.bufferline").get_theme({
         styles = { "italic", "bold" },
         custom = {
           all = {

nvim/lua/plugins/npm-servers.lua

@@ -0,0 +1,60 @@
+-- Some language servers are distributed only as npm packages, and Node on Arch
+-- ships without npm. Without this guard you get two separate rounds of errors:
+--
+--   1. mason-lspconfig retries the install on every startup and fails, once per
+--      server ("failed to install yamlls" ...).
+--   2. LazyVim still enables the server, so opening any matching file fails with
+--      "Spawning language server with cmd: { "yaml-language-server", ... } failed".
+--
+-- So each server below is disabled unless its binary can actually be found.
+-- Nothing is hardcoded to this host: the check is a PATH lookup plus Mason's own
+-- bin directory, so the moment the server exists it enables itself again.
+--
+-- To get them: sudo pacman -S npm
+--              nvim +"MasonInstall yaml-language-server dockerfile-language-server" +qa
+
+-- LazyVim server name -> the executable Mason/npm installs for it.
+local npm_servers = {
+  yamlls = "yaml-language-server",
+  dockerls = "docker-langserver",
+  docker_compose_language_service = "docker-compose-langserver",
+}
+
+local mason_bin = vim.fs.joinpath(vim.fn.stdpath("data"), "mason", "bin")
+
+---@param bin string
+---@return boolean
+local function available(bin)
+  if vim.fn.executable(bin) == 1 then
+    return true
+  end
+  -- Mason prepends its bin dir to PATH only after setup, so look there directly.
+  return vim.uv.fs_stat(vim.fs.joinpath(mason_bin, bin)) ~= nil
+end
+
+local missing = {}
+for server, bin in pairs(npm_servers) do
+  if not available(bin) then
+    missing[#missing + 1] = server
+  end
+end
+
+if #missing == 0 then
+  return {}
+end
+
+return {
+  {
+    "neovim/nvim-lspconfig",
+    opts = function(_, opts)
+      opts.servers = opts.servers or {}
+      for _, server in ipairs(missing) do
+        opts.servers[server] = vim.tbl_deep_extend("force", opts.servers[server] or {}, {
+          enabled = false, -- do not try to spawn a binary that is not there
+          mason = false, -- and do not retry the impossible install every startup
+        })
+      end
+      return opts
+    end,
+  },
+}

nvim/lua/plugins/project-run.lua

@@ -0,0 +1,55 @@
+-- Keymaps for the language-aware project runner in lua/util/project.lua.
+--
+-- <leader>r is already the refactoring group, so the run/project verbs live
+-- under <leader>R. Each verb dispatches on the detected project type, so the
+-- same key does the right thing in a Rust crate, a Python package or a Zephyr
+-- application.
+
+local function p(fn)
+  return function()
+    require("util.project")[fn]()
+  end
+end
+
+return {
+  {
+    "folke/snacks.nvim",
+    -- Remember the last real file buffer, so the run verbs still know which
+    -- project you are in after one of them has opened a terminal (at which
+    -- point the focused buffer is the terminal, not your code).
+    init = function()
+      vim.api.nvim_create_autocmd({ "BufEnter", "BufWinEnter" }, {
+        group = vim.api.nvim_create_augroup("project_run_last_file", { clear = true }),
+        callback = function(ev)
+          if vim.bo[ev.buf].buftype == "" then
+            local name = vim.api.nvim_buf_get_name(ev.buf)
+            if name ~= "" then
+              vim.g.project_last_file = name
+            end
+          end
+        end,
+      })
+    end,
+    -- stylua: ignore
+    keys = {
+      { "<leader>R",  "",              desc = "+run/project" },
+      { "<leader>Rr", p("run"),        desc = "Run project" },
+      { "<leader>Rf", p("run_file"),   desc = "Run current file" },
+      { "<leader>Rb", p("build"),      desc = "Build" },
+      { "<leader>Rt", p("test"),       desc = "Test" },
+      { "<leader>RF", p("flash"),      desc = "Build + Flash (Zephyr)" },
+      { "<leader>Rs", p("select_target"), desc = "Select target/board" },
+      { "<leader>Rk", p("configure"),  desc = "Configure (menuconfig/clippy)" },
+      { "<leader>Rc", p("clean"),      desc = "Clean" },
+      { "<leader>Ri", p("info"),       desc = "Project info" },
+    },
+  },
+  {
+    "folke/which-key.nvim",
+    opts = {
+      spec = {
+        { "<leader>R", group = "run/project", icon = " " },
+      },
+    },
+  },
+}

nvim/lua/util/project.lua

@@ -0,0 +1,389 @@
+-- Language-aware project runner.
+--
+-- Detects what kind of project the current buffer lives in and exposes a small
+-- set of verbs (run / run file / build / test / flash / ...) that map onto the
+-- right tool for that project. Bound under <leader>R -- see
+-- lua/plugins/project-run.lua.
+--
+-- Everything is discovered from the project on disk; nothing is hardcoded to a
+-- machine, and per-project choices (like the Zephyr board) are cached in
+-- stdpath("state") rather than written into the repo.
+
+local M = {}
+
+---------------------------------------------------------------------------
+-- helpers
+---------------------------------------------------------------------------
+
+--- The file the project should be judged from.
+---
+--- Not simply the current buffer: after one of these verbs opens a terminal,
+--- that terminal is the focused buffer, and walking up from it finds no project
+--- markers. So prefer the focused buffer only when it is a real file, and
+--- otherwise fall back to the most recently used normal buffer, then cwd.
+---@return string
+function M.source_path()
+  local buf = vim.api.nvim_get_current_buf()
+  if vim.bo[buf].buftype == "" then
+    local name = vim.api.nvim_buf_get_name(buf)
+    if name ~= "" then
+      return name
+    end
+  end
+
+  -- Tracked by the autocmd in lua/plugins/project-run.lua.
+  local last = vim.g.project_last_file
+  if type(last) == "string" and last ~= "" then
+    return last
+  end
+
+  return vim.uv.cwd()
+end
+
+---@param markers string[]
+---@return string|nil
+local function root_with(markers)
+  return vim.fs.root(M.source_path(), markers)
+end
+
+local function exists(path)
+  return path and vim.uv.fs_stat(path) ~= nil
+end
+
+--- Run a command in a terminal at `cwd` so you can watch it and answer prompts.
+local function term(cmd, cwd, opts)
+  opts = opts or {}
+  local ok, Snacks = pcall(require, "snacks")
+  if ok and Snacks.terminal then
+    Snacks.terminal.open(cmd, {
+      cwd = cwd,
+      interactive = true,
+      win = { position = opts.position or "float" },
+    })
+  else
+    vim.cmd("botright split | terminal " .. cmd)
+  end
+  vim.notify(cmd, vim.log.levels.INFO, { title = "project" })
+end
+
+--- Prefer a project-local virtualenv interpreter when there is one.
+local function python_for(root)
+  for _, rel in ipairs({ ".venv/bin/python", "venv/bin/python" }) do
+    local p = vim.fs.joinpath(root, rel)
+    if exists(p) then
+      return vim.fn.shellescape(p)
+    end
+  end
+  return "python3"
+end
+
+---------------------------------------------------------------------------
+-- per-project state (board selection, etc.)
+---------------------------------------------------------------------------
+
+local state_file = vim.fs.joinpath(vim.fn.stdpath("state"), "project-run.json")
+
+local function load_state()
+  if not exists(state_file) then
+    return {}
+  end
+  local ok, data = pcall(function()
+    return vim.json.decode(table.concat(vim.fn.readfile(state_file), "\n"))
+  end)
+  return (ok and type(data) == "table") and data or {}
+end
+
+local function save_state(tbl)
+  pcall(vim.fn.writefile, vim.fn.split(vim.json.encode(tbl), "\n"), state_file)
+end
+
+---@param root string
+---@param key string
+function M.get_setting(root, key)
+  local s = load_state()
+  return (s[root] or {})[key]
+end
+
+---@param root string
+---@param key string
+---@param value any
+function M.set_setting(root, key, value)
+  local s = load_state()
+  s[root] = s[root] or {}
+  s[root][key] = value
+  save_state(s)
+end
+
+---------------------------------------------------------------------------
+-- project detection
+---------------------------------------------------------------------------
+
+--- Order matters: a Zephyr app is also a CMake project, so it must win.
+local DETECT = {
+  { type = "zephyr", markers = { "west.yml", ".west", "prj.conf" } },
+  { type = "rust", markers = { "Cargo.toml" } },
+  { type = "python", markers = { "pyproject.toml", "setup.py", "requirements.txt" } },
+  { type = "cmake", markers = { "CMakeLists.txt", "CMakePresets.json" } },
+  { type = "make", markers = { "Makefile" } },
+}
+
+---@return string type, string root
+function M.detect()
+  for _, d in ipairs(DETECT) do
+    local root = root_with(d.markers)
+    if root then
+      -- A Zephyr app has prj.conf next to CMakeLists.txt; plain CMake does not.
+      return d.type, root
+    end
+  end
+  return "unknown", vim.uv.cwd()
+end
+
+function M.info()
+  local t, root = M.detect()
+  local extra = ""
+  if t == "zephyr" then
+    extra = "  board: " .. (M.get_setting(root, "board") or "<not set>")
+  end
+  vim.notify(("project: %s\nroot: %s%s"):format(t, root, extra), vim.log.levels.INFO, { title = "project" })
+end
+
+---------------------------------------------------------------------------
+-- Zephyr
+---------------------------------------------------------------------------
+
+local board_list_cache = nil
+
+--- `west boards` walks the whole tree and is slow, so cache the result.
+local function zephyr_boards(root, cb)
+  if board_list_cache then
+    return cb(board_list_cache)
+  end
+  vim.notify("listing boards (west boards)...", vim.log.levels.INFO, { title = "zephyr" })
+  vim.system({ "west", "boards", "-f", "{name}" }, { cwd = root, text = true }, function(res)
+    vim.schedule(function()
+      if res.code ~= 0 then
+        vim.notify("west boards failed:\n" .. (res.stderr or ""), vim.log.levels.ERROR, { title = "zephyr" })
+        return cb({})
+      end
+      local boards = {}
+      for _, line in ipairs(vim.split(res.stdout or "", "\n")) do
+        line = vim.trim(line)
+        if line ~= "" then
+          boards[#boards + 1] = line
+        end
+      end
+      table.sort(boards)
+      board_list_cache = boards
+      cb(boards)
+    end)
+  end)
+end
+
+--- Pick a board with the configured fuzzy picker (vim.ui.select is routed to it).
+---@param root string
+---@param cb fun(board:string)|nil
+function M.zephyr_select_board(root, cb)
+  root = root or select(2, M.detect())
+  zephyr_boards(root, function(boards)
+    if #boards == 0 then
+      return
+    end
+    vim.ui.select(boards, { prompt = "Zephyr board:" }, function(choice)
+      if not choice then
+        return
+      end
+      M.set_setting(root, "board", choice)
+      vim.notify("board = " .. choice, vim.log.levels.INFO, { title = "zephyr" })
+      if cb then
+        cb(choice)
+      end
+    end)
+  end)
+end
+
+--- Get the board, prompting for one if it has not been chosen yet.
+local function with_board(root, cb)
+  local board = M.get_setting(root, "board")
+  if board then
+    return cb(board)
+  end
+  M.zephyr_select_board(root, cb)
+end
+
+local function zephyr_build_dir(root)
+  return M.get_setting(root, "build_dir") or "build"
+end
+
+---------------------------------------------------------------------------
+-- verbs
+---------------------------------------------------------------------------
+
+--- Primary "run this project".
+function M.run()
+  local t, root = M.detect()
+  if t == "rust" then
+    term("cargo run", root)
+  elseif t == "python" then
+    local py = python_for(root)
+    -- main.py at the root wins; then any package with a __main__.py.
+    if exists(vim.fs.joinpath(root, "main.py")) then
+      term(py .. " main.py", root)
+      return
+    end
+    local mains = vim.fs.find("__main__.py", { path = root, type = "file", limit = 5 })
+    if #mains > 0 then
+      local dir = vim.fs.dirname(mains[1])
+      local pkg = vim.fs.basename(dir)
+      local parent = vim.fs.dirname(dir)
+      -- run as a module so intra-package imports resolve
+      term(("PYTHONPATH=%s %s -m %s"):format(vim.fn.shellescape(parent), py, pkg), root)
+      return
+    end
+    M.run_file()
+  elseif t == "zephyr" then
+    M.flash()
+  elseif t == "cmake" then
+    -- run the first executable cmake produced, if we can find one
+    local bin = vim.fs.find(function(name, path)
+      return path:match("/build$") ~= nil and vim.fn.executable(vim.fs.joinpath(path, name)) == 1
+    end, { path = vim.fs.joinpath(root, "build"), type = "file", limit = 1 })[1]
+    if bin then
+      term(vim.fn.shellescape(bin), root)
+    else
+      vim.notify("no executable found in build/ -- build first", vim.log.levels.WARN, { title = "project" })
+    end
+  elseif t == "make" then
+    term("make run", root)
+  else
+    M.run_file()
+  end
+end
+
+--- Run just the current file.
+function M.run_file()
+  local file = M.source_path()
+  if file == "" or vim.fn.filereadable(file) == 0 then
+    return vim.notify("no file to run", vim.log.levels.WARN, { title = "project" })
+  end
+  local _, root = M.detect()
+  local ft = vim.filetype.match({ filename = file }) or vim.bo.filetype
+  local runners = {
+    python = function()
+      return python_for(root) .. " " .. vim.fn.shellescape(file)
+    end,
+    lua = function()
+      return "lua " .. vim.fn.shellescape(file)
+    end,
+    sh = function()
+      return "bash " .. vim.fn.shellescape(file)
+    end,
+    rust = function()
+      return "cargo run"
+    end,
+    go = function()
+      return "go run " .. vim.fn.shellescape(file)
+    end,
+  }
+  local build = runners[ft]
+  if not build then
+    -- Compiled languages have no meaningful "run this one file"; say what to
+    -- use instead rather than just refusing.
+    return vim.notify(
+      ("no single-file runner for '%s' -- use <leader>Rr to run the project"):format(ft),
+      vim.log.levels.WARN,
+      { title = "project" }
+    )
+  end
+  term(build(), root)
+end
+
+function M.build()
+  local t, root = M.detect()
+  if t == "zephyr" then
+    with_board(root, function(board)
+      term(("west build -b %s -d %s ."):format(board, zephyr_build_dir(root)), root)
+    end)
+  elseif t == "rust" then
+    term("cargo build", root)
+  elseif t == "cmake" then
+    term("cmake -S . -B build -DCMAKE_EXPORT_COMPILE_COMMANDS=ON && cmake --build build", root)
+  elseif t == "make" then
+    term("make", root)
+  elseif t == "python" then
+    term(python_for(root) .. " -m build", root)
+  else
+    vim.notify("no build for project type '" .. t .. "'", vim.log.levels.WARN, { title = "project" })
+  end
+end
+
+function M.test()
+  local t, root = M.detect()
+  if t == "rust" then
+    term("cargo test", root)
+  elseif t == "python" then
+    term(python_for(root) .. " -m pytest", root)
+  elseif t == "zephyr" then
+    with_board(root, function(board)
+      term(("west twister -p %s -T ."):format(board), root)
+    end)
+  elseif t == "cmake" then
+    term("ctest --test-dir build --output-on-failure", root)
+  elseif t == "make" then
+    term("make test", root)
+  else
+    vim.notify("no test for project type '" .. t .. "'", vim.log.levels.WARN, { title = "project" })
+  end
+end
+
+--- Zephyr flash (and the obvious analogue elsewhere).
+function M.flash()
+  local t, root = M.detect()
+  if t ~= "zephyr" then
+    return vim.notify("flash is Zephyr-only (project is '" .. t .. "')", vim.log.levels.WARN, { title = "project" })
+  end
+  with_board(root, function(board)
+    term(("west build -b %s -d %s . && west flash -d %s"):format(board, zephyr_build_dir(root), zephyr_build_dir(root)), root)
+  end)
+end
+
+function M.clean()
+  local t, root = M.detect()
+  if t == "zephyr" then
+    term("west build -t pristine -d " .. zephyr_build_dir(root), root)
+  elseif t == "rust" then
+    term("cargo clean", root)
+  elseif t == "cmake" then
+    term("cmake --build build --target clean", root)
+  elseif t == "make" then
+    term("make clean", root)
+  else
+    vim.notify("no clean for project type '" .. t .. "'", vim.log.levels.WARN, { title = "project" })
+  end
+end
+
+--- Zephyr menuconfig / rust clippy / python lint -- the "configure" slot.
+function M.configure()
+  local t, root = M.detect()
+  if t == "zephyr" then
+    term("west build -t menuconfig -d " .. zephyr_build_dir(root), root)
+  elseif t == "rust" then
+    term("cargo clippy --all-targets", root)
+  elseif t == "cmake" then
+    term("cmake -S . -B build -DCMAKE_EXPORT_COMPILE_COMMANDS=ON", root)
+  else
+    vim.notify("nothing to configure for '" .. t .. "'", vim.log.levels.WARN, { title = "project" })
+  end
+end
+
+--- Select the target: Zephyr board today, extensible later.
+function M.select_target()
+  local t, root = M.detect()
+  if t == "zephyr" then
+    M.zephyr_select_board(root)
+  else
+    vim.notify("no target to select for project type '" .. t .. "'", vim.log.levels.WARN, { title = "project" })
+  end
+end
+
+return M