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

Install

vim.pack.add("swaits/tiny-debugger.nvim")

That's it. No other config needed.

What You Get

Inline virtual text — variable values appear right in your source code, updated live as you step
Hover inspection — press K on any expression to see its value
Persistent breakpoints — survive Neovim restarts, visible in the sign column at all times
Watch expressions — press W to add the expression under your cursor
Scopes panel — all local/global variables in the current frame
Stack traces — navigate the call stack, jump to any frame
REPL — evaluate arbitrary expressions in the debug context
Console — program stdout/stderr
Modal keybindings — single-key controls, active only during debug sessions
Help box — shows all keybindings, re-openable with ?
Zero-config adapters for 10+ languages

UI Layout

┌──────────────────────────────────┬──────────────────┐
│                                  │ Scopes     (50%) │
│          Source Code              │                  │
│                                  ├──────────────────┤
│     x = 42  -- « virtual text    │ Watches    (25%) │
│                                  ├──────────────────┤
│                                  │ Stacks     (25%) │
├──────────────────────────────────┴──────────────────┤
│ REPL (50%)               │ Console (50%)            │
└──────────────────────────┴──────────────────────────┘

Keybindings

<leader>d toggles debug mode. During debug mode:

Key	Action	Mnemonic
`c`	Continue	Continue
`s`	Step over	Step
`d`	Step into	Descend
`r`	Step out	Return
`C`	Run to cursor	Continue to cursor
`x`	Toggle breakpoint	X marks the spot
`X`	Conditional breakpoint	Shift-x
`W`	Watch expression	Watch
`K`	Hover / inspect	LSP hover convention
`E`	Eval in REPL	Evaluate
`q`	Terminate session	Quit
`R`	Restart session	Rerun
`?`	Help popup	Help

x and X work outside debug mode too.

All navigation keys preserved: h j k l w b e f / n etc.

Supported Languages

Language	Adapter	Binary needed
Python	debugpy	`python -m debugpy`
JavaScript / TS	js-debug	`js-debug-adapter`
Go	delve	`dlv`
C / C++	codelldb	`codelldb`
Rust	codelldb	`codelldb`
Swift	codelldb	`codelldb`
C#	netcoredbg	`netcoredbg`
Java	java-debug	`java-debug-adapter`
Kotlin	kotlin-debug	`kotlin-debug-adapter`
PHP	php-debug	`php-debug-adapter`
Ruby	rdbg	`rdbg`
Lua (Neovim)	osv	one-small-step-for-vimkind

Adapter binaries are the user's responsibility to install (via mason, system package manager, or manually). tiny-debugger configures, it doesn't install.

Configuration (optional)

require("tiny-debugger").setup({
  help_on_enter = true,       -- show help box when entering debug mode
  builtin_adapters = true,    -- register built-in language adapters

  keys = {
    continue = "c",           -- override any key
    step_over = false,        -- set to false to disable
  },

  adapters = {
    zig = { ... },            -- add new language adapters
  },

  dapui = { ... },            -- override nvim-dap-ui layout
  virtual_text = { ... },     -- override virtual text settings
})

Statusline

require("tiny-debugger").active()  -- returns true/false

Help

:help tiny-debugger

License

MIT