turbo-debug.nvim

A zero-config debugging experience for Neovim 0.12+. One plugin install, full IDE-class debugging: inline variable values, hover inspection, persistent breakpoints, watch expressions, and modal keybindings that just work.

Inspired by Turbo Pascal — the first IDE where you could just hit a key and start debugging.

Install

vim.pack.add("swaits/turbo-debug")

That's it. No other config needed. See :help turbo-debug for customization.

How It Works

turbo-debug is modal. Press <leader>dd and you enter debug mode — the dap-ui layout opens, keybindings activate, virtual text lights up, and you're debugging. Press <leader>dd again (or q) and everything disappears: the session terminates, the UI closes, and every keybinding is restored to exactly what it was.

This modal approach is inspired by debugmaster.nvim. During a debug session you navigate code and inspect state; you don't edit. So debug mode shadows editing keys (c, d, s, r, x) with debug actions and leaves all navigation keys untouched (h, j, k, l, w, b, e, f, /, n, etc.).

A nice text and GUI debugger

The modal keymap is deliberately left-hand optimized so the right hand stays on the mouse for interacting with the dap-ui panes:

• Left hand on keyboard: c s d r C x X D W E q R fire the twelve rapid-use debug actions without leaving home row.
• Right hand on mouse: click into Watches/Scopes/Stacks/Breakpoints panes to expand trees, jump to frames, add watch expressions, or toggle breakpoints from the GUI.

Only two modal keys live on the right hand, both by universal convention: K for hover (matches the LSP hover key) and ? for help.

Inside dap-ui panes, the native dap-ui mappings still work — d removes a watch, r sends to REPL, e edits. The modal d (step-into) and r (step-out) yield to dap-ui in those buffers so you can manage the GUI without exiting debug mode.

Keybindings

Everything lives under <leader>d (with which-key support if installed):

Key	Action
<leader>dd	Toggle debug mode
<leader>dx	Toggle breakpoint
<leader>dX	Conditional breakpoint
<leader>dD	Clear all breakpoints

During debug mode, single-key controls:

Key	Action	Key	Action
c	Continue	x	Toggle breakpoint
s	Step over	X	Conditional breakpoint
d	Step into	D	Clear all breakpoints
r	Step out	W	Watch expression
C	Run to cursor	K	Hover / inspect
q	Smart quit (terminate → exit)	E	Eval in REPL
R	Restart session	?	Help popup

q is context-aware: if a session is running, it terminates the session and leaves you in debug mode (so you can read the console and inspect the exit state). If no session is running, q exits debug mode entirely.

Press ? during debug mode for a quick reference that also lists dap-ui's native in-pane bindings (<CR>, e, o, d, r, t).

Extending keymaps

Every key is user-overridable. Remap, disable, or add bindings via setup():

require("turbo-debug").setup({
  keys = {
    step_over = "n",       -- remap a modal key
    watch = false,         -- disable a modal key
  },
  global_keys = {
    toggle = "<leader>D",  -- change the toggle chord
  },
  sidebar = "right",       -- "left" (default) or "right"
  help_on_enter = true,    -- show help popup on debug mode entry (default false)

  -- Optional theme swap for debug sessions. `nil` (default) keeps the
  -- current colorscheme; any string is passed to `:colorscheme` on enter
  -- and the original is restored on exit.
  colorscheme = nil,

  -- Auto stop-on-entry when no breakpoints are set (Turbo Pascal model):
  -- press `c` on an empty-BP project and the debugger pauses at main().
  -- Set false to always run until a breakpoint instead.
  stop_on_entry_when_no_breakpoints = true,

  -- Cap per-line value length in Scopes/Watches. Values longer than this
  -- get truncated with `…`. Default 2000 only catches pathological register
  -- dumps. Set 0 to disable truncation entirely.
  max_value_width = 2000,

  -- Console repaint throttle (ms). Max 1000/console_refresh_ms redraws per
  -- second when the debugged program spams stdout. Prevents editor DOS.
  console_refresh_ms = 50,

  -- Clear the Console pane on session start/restart (preserves the
  -- terminal channel — only wipes scrollback).
  clear_console_on_start = true,

  -- Scope names to default-collapse in Scopes. dapui auto-collapses any
  -- scope the adapter marks `expensive`, but codelldb doesn't flag
  -- Registers as expensive even though it's a huge dump.
  collapsed_scopes = { "Registers" },

  -- Dim inactive dapui pane borders so the focused pane is obvious.
  active_window_highlight = true,
})

Chrome bars

When debug mode is active, two 2-row floating bars appear, completely independent of lualine, heirline, or any other statusline plugin:

Status bar (top) shows:

• The turbo-debug brand
• Live dap.status() progress text
• Session state chip: DEBUG · READY / · RUNNING / · PAUSED (color-coded via DiagnosticHint / DiagnosticInfo / DiagnosticError)

Control bar (bottom, above your statusline) shows:

• Clickable buttons: (c)ontinue / (s)tep over / (d)escend into / (r)eturn out / (R)estart (during session) / (q) terminate
• (?) help right-anchored
• Italic qualifiers (over, into, out) are inline when width allows; auto-dropped on narrow terminals

Both bars:

• Recreate themselves if killed by layout changes (bufferline tabline toggles, wincmd =, etc.)
• Re-render on every DAP state change (|User DapProgressUpdate|)
• Close cleanly on exit

Design notes

• Rounded borders are on every floating window this plugin opens: the help popup (?), the hover popup (K), and the debug-eval popup (E). Floating windows are the only windows Neovim draws borders around in the terminal grid. Splits (the Scopes/Watches/Stacks/Breakpoints/ Console panes) use the user's WinSeparator character — that's a terminal-rendering limit, not a plugin choice.

• No hardcoded colors. Every highlight links to a standard group (DiagnosticError, Function, Comment, CursorLine, Visual, Search, Title, Special, WinBar, etc.) so the plugin automatically inherits your colorscheme on the fly. Switch themes mid-session (or set colorscheme = "high-contrast" in setup() for a dedicated debug theme) and everything re-paints.

• Emoji (supplementary-plane, not VS16-dependent) for iconography: 🔴 🟡 ⭕ 👉 📝 for gutter signs; 🟢 🚀 👣 🔽 🔼 🔄 🛑 for control buttons; 🔎 👀 📚 🔴 💻 for pane titles. Colored emoji render consistently in modern terminals (Ghostty, Kitty, WezTerm, iTerm) without font-dependent rendering quirks.

Supported Languages

turbo-debug ships adapter configs for 22 languages. You install the adapter binary (via mason.nvim, your package manager, or manually) — turbo-debug handles all the configuration.

Language	Adapter	Language	Adapter
Python	debugpy	C#	netcoredbg
JavaScript / TS	js-debug	F#	netcoredbg
Go	delve	Java	java-debug-adapter
C / C++	codelldb	Kotlin	kotlin-debug
Rust	codelldb	PHP	php-debug
Swift	codelldb	Ruby	rdbg
Zig	codelldb	Elixir	elixir-ls
Nim	codelldb	Haskell	haskell-debug-adapter
Crystal	codelldb	OCaml	ocamlearlybird
Dart / Flutter	dart-debug	R	vscDebugger
Bash / Sh	bash-debug-adapter	Lua (Neovim)	osv

Special treatment:

• Rust: pressing c runs cargo build automatically and picks the binary via vim.ui.select.
• Python: auto-detects virtualenvs (VIRTUAL_ENV, CONDA_PREFIX, .venv, venv, env, .env).
• Dart: if flutter is on PATH, a "Launch Flutter app" configuration is added alongside the plain Dart file launch.
• R: preflights that the vscDebugger R package is installed; silently skips registration if missing.

What This Plugin Actually Does

turbo-debug is glue. It does not implement a debugger, a UI framework, virtual text rendering, or breakpoint persistence. It configures and wires together these excellent plugins into a single cohesive experience:

Plugin	What it provides
nvim-dap	DAP client — the core debug engine
nvim-dap-ui	Scopes, stacks, watches, REPL, console UI
nvim-nio	Async IO (required by nvim-dap-ui)
nvim-dap-virtual-text	Inline variable values in source code
persistent-breakpoints.nvim	Breakpoints that survive restarts

All five are loaded automatically via vim.pack.add. You never declare them.

Adapter configurations are inlined from the work of these projects (no runtime dependency, we just studied their configs and wrote plain Lua tables):

• nvim-dap-python
• nvim-dap-go
• nvim-dap-vscode-js
• nvim-dap-lldb
• nvim-dap-cs
• nvim-dap-ruby
• nvim-dap-kotlin

License

MIT