nvim-markview

Real-time Markdown browser preview for Neovim — no Node.js or pandoc required.

Features

• Live preview in your default browser via Server-Sent Events (SSE)
• Pure Lua implementation using vim.uv (libuv) — zero external dependencies
• Azure DevOps-compatible Markdown rendering (wiki / pull request syntax)
• Syntax highlighting via highlight.js (CDN, internet required)
• Mermaid diagram rendering via mermaid.js (CDN, internet required)
• Auto dark/light theme following OS prefers-color-scheme
• Scroll position preserved on updates
• Multiple buffer support
• Local images with relative paths are served automatically from the Markdown file's directory

Requirements

• Neovim 0.10+
• A web browser

Installation

lazy.nvim

{
  "halkn/nvim-markview",
  ft = "markdown",
  opts = {},
}

packer.nvim

use {
  "halkn/nvim-markview",
  config = function()
    require("markview").setup()
  end,
}

Usage

Open a Markdown file, then:

Command	Description
:MarkviewOpen	Start the preview server and open browser
:MarkviewClose	Stop the preview server
:MarkviewToggle	Toggle the preview

Default keymap: <leader>mp to toggle.

Supported Syntax

Basic

Element	Syntax
Headings	# H1 — ###### H6 (ATX only)
Bold	**text** or __text__
Italic	*text* or _text_
Strikethrough	~~text~~
Inline code	`code`
Link	[text](url)
Image	 — relative paths served from the file's directory
Hard line break	Two trailing spaces
Horizontal rule	---

Blocks

Element	Syntax
Fenced code block	```lang … ```
Unordered list	- item or * item
Ordered list	1. item
Task list	- [ ] todo / - [x] done
Blockquote	> text (nestable)
GFM table	Pipe-separated with separator row

Azure DevOps Extensions

Element	Syntax
Admonitions	> [!NOTE] / > [!TIP] / > [!WARNING] / > [!IMPORTANT] / > [!CAUTION]
Mermaid diagram	::: mermaid … ::: or ```mermaid … ```

Configuration

require("markview").setup({
  port        = 8765,    -- HTTP server starting port
  auto_open   = false,   -- auto-preview when opening *.md files
  debounce_ms = 200,     -- delay (ms) before pushing SSE update
  browser     = nil,     -- nil = OS default (xdg-open / open / start)
  theme       = "auto",  -- "auto" | "light" | "dark"
  keymaps     = {
    toggle = "<leader>mp",
  },
})

How It Works

[Neovim buffer] ──TextChanged──> [debounce] ──> [server.push(md)]
                                                      |
                                            [parser.render(md)]
                                                      |
                                            [SSE: data: html]
                                                      |
                                            [Browser DOM update]

vim.uv.new_tcp() runs a lightweight HTTP server inside Neovim's event loop.

Endpoint	Description
GET /	Serves the initial full HTML page
GET /events	Persistent SSE connection — pushes re-rendered HTML on every change
GET /images/<path>	Serves a local image file relative to the Markdown file's directory

Every buffer change triggers a debounced push of re-rendered HTML to all connected browser tabs. Relative image paths in the Markdown (e.g. ![screenshot](./imgs/foo.png)) are rewritten to /images/imgs/foo.png and served from disk. Path traversal (..) is blocked.

License

MIT