mdmini

A minimalist live-preview markdown editor for macOS.

You edit raw markdown and see it rendered inline — no split panes, no mode switching. Built with Tauri 2, Svelte 5, and CodeMirror 6.

Website · Releases

Install

brew tap malinborn/mdmini
brew trust malinborn/mdmini
brew install --cask mdmini

Or download the .dmg from Releases.

After an update, macOS asks for folder access again

Expected, and not something an update can avoid. mdmini is ad-hoc signed — no Apple Team ID — so macOS identifies it by a code hash that changes with every release. After brew upgrade, the permission you granted to Documents or Desktop belongs to what macOS considers a different app, and it asks once more.

Fixing it properly means Developer ID signing and notarization, which costs $99/year. mdmini is free and open source, and that is not a bill it is going to carry. Granting access again after an upgrade is the whole of the workaround.

Usage

mdmini                    # Open empty editor
mdmini README.md          # Open a file
mdmini file1.md file2.md  # Open multiple files

What it does

Editor — live-preview decorations that hide markdown syntax when your cursor moves away. Headings, bold, italic, strikethrough, links, code, blockquotes, lists, checkboxes — all rendered inline.

Tables — rendered as interactive widgets with aligned columns. Double-click to edit cells. Drag ⠿ handles to reorder rows and columns. Hover for +/− buttons. Inline code, bold, italic inside cells.

Code blocks — syntax highlighting for 100+ languages with language label and Copy button. Click a code block to edit, click away to preview.

Mermaid diagrams — flowcharts, sequence, class, state, ER, Gantt, pie, gitgraph, and mindmap render as inline SVG. Lazy-loaded, theme-aware, with error overlay while editing.

Collapsible headings — hover any heading to reveal a fold toggle. Click to collapse the section.

.env files — opens with secret masking (keys like PASSWORD, TOKEN, API_KEY are hidden). Copy button copies the full value. Cmd+E toggles raw view.

Code files — .py, .rs, .json, .yaml and others open with native syntax highlighting.

File watcher — detects external changes (e.g., from AI agents editing the file) and auto-reloads. Cmd+Z to undo.

Links — click rendered links to open in browser.

Themes — dark (Rosé Pine) and light, switchable via menu. Gradient table headers.

Keyboard Shortcuts

Development

npm install
npm run tauri dev

If port 1420 is stuck: lsof -ti:1420 | xargs kill -9

Build

npm run tauri build

Tests

npm run test          # Vitest (frontend)
cargo test            # Rust (cd src-tauri)
npm run check         # Svelte types

Tech Stack

Tauri 2 · Svelte 5 · CodeMirror 6 · Lezer (markdown parser) · Vite

License

GPL-3.0