A CLI tool that renders Markdown files in the browser with GitHub-style formatting and live reload on file changes.

• GitHub Flavored Markdown (GFM) — tables, strikethrough, autolinks, task lists
• Server-side syntax highlighting via Chroma — no client-side JS
• Mermaid diagrams from fenced mermaid blocks, rendered in-browser on demand
• Live reload via SSE — browser updates without full page reload, scroll position preserved
• PDF export — --pdf output.pdf flag (headless Chrome) or "Export PDF" button in the browser
• Serves relative local assets from the Markdown directory (e.g. ![demo](./recording.gif))
• Auto-increments port if the default is taken (up to 20 attempts)
• Binds to 127.0.0.1 only — no LAN exposure

go install github.com/Allra-Fintech/mdv@latest

Or via Homebrew:

brew tap Allra-Fintech/tap
brew install Allra-Fintech/tap/mdv

Note: There is an unrelated Python tool also named mdv in homebrew-core. Use the fully-qualified name Allra-Fintech/tap/mdv to install this one.

Or build from source:

git clone https://github.com/Allra-Fintech/mdv
cd mdv
make install        # installs to ~/.local/bin (default) as mdv
# PREFIX=/usr/local make install   # custom prefix

mdv [flags] <file.md>

# Open README.md in browser with live reload
mdv README.md

# Use a custom port and dark highlight theme
mdv --port 8080 --theme monokai README.md

# Print URL but don't open browser
mdv --no-browser README.md

# Export to PDF (requires Chrome or Chromium)
mdv --pdf output.pdf README.md

# Render Mermaid diagrams in fenced mermaid blocks
mdv diagrams.md

Example Mermaid block:

```mermaid
flowchart TD
  Start --> Ship
```

cmd/mdv/main.go            — CLI flag parsing, resolvePort, openBrowser, wiring
internal/mdv/server.go     — HTTP routes: GET /, GET /content, GET /events (SSE)
internal/mdv/renderer.go   — goldmark setup with GFM, Chroma highlighting, Mermaid block handling
internal/mdv/hub.go        — SSE broadcast hub (Register/Unregister/Broadcast)
internal/mdv/watcher.go    — fsnotify file watcher → hub.Broadcast()
internal/mdv/template.go   — Full HTML page template (inline CSS + SSE JS, Mermaid loader)
internal/mdv/pdf.go        — Headless Chrome PDF export (findChrome, PrintToPDF, WaitForServer)

Data flow:

fsnotify event → WatchFile() → hub.Broadcast()
                                    ↓
                         SSE clients (/events) receive "reload"
                                    ↓
                    Browser fetches /content → swaps #content innerHTML

Common themes: github, github-dark, monokai, dracula, solarized-dark, vs, xcode.

Full list: https://xyproto.github.io/splash/docs/

grip sends your Markdown to the GitHub API for rendering — requires a token for heavy use and doesn't work offline. glow renders in the terminal, which is great for quick reads but loses fidelity for complex tables, images, and diagrams. mdv renders locally in your browser with GitHub-style CSS, live reload as you edit, and zero external API calls.