PicaMD

A small, native Markdown editor and viewer for macOS.

Open a .md file and it reads like a finished document. Put the cursor on a line and that line turns back into Markdown; move on and it renders again. Your files stay plain text wherever you keep them. No library, no vault, no account. Built with AppKit, not a web view.

Features

• Live preview in place. **, _, `, #, >, links and the like hide when the cursor isn't on them.
• Rendered blocks. Tables, images, math (KaTeX, bundled) and Mermaid diagrams render inline.
• Task lists with clickable checkboxes.
• Format menu for headings, bold, italic, strikethrough, code, links, checklists, quotes and tables, each a toggle on the selection or the word at the caret. Shortcuts can be changed in keybindings.json.
• Outline sidebar, an inspector with editable front matter (title, tags, date) and document statistics (⌥⌘I), a quiet word count, footnote previews. Front matter collapses to one grey line until the caret enters it.
• Find & Replace (⌘F) in a bar under the toolbar, with Wrap Around, Starts With / Whole Word, regular expressions and an option to ignore formatting so bold word also finds **bold** word.
• Focus, typewriter and reflow modes, tabs, and a command palette (⇧⌘P) for headings, the View and Format commands, Find, Export, Settings and, while AI is on, the AI presets.
• Themes. Three presets, four palettes plus your own text and background colour, seven accent colours, any installed font, and a readable line width. The editor's colours work independently of the system's light/dark setting.
• Export to HTML. PDF, DOCX and EPUB also work if pandoc is installed.
• Spotlight and Services. Find your notes in Spotlight, and use Open Selection in PicaMD from other apps. A Quick Look extension is included but loads only once the app is signed with a Developer ID (see Known limitations).

Optional extras

These are off until you turn them on, and stay out of the way otherwise.

• AI presets. Send a selection to Anthropic, OpenAI, Apple Intelligence or your own OpenAI-compatible server (Ollama, LM Studio, vLLM, on this Mac or another one) with ⌃⌘1–⌃⌘9, or pick a preset with ⌃Space. Presets are editable. API keys are kept in the Keychain. Apple Intelligence runs on the Mac without a key; its context window is small, so a long selection is refused before anything runs, with a pointer to Anthropic or OpenAI.

• MCP server. The app bundle includes picamd-mcp, which lets Claude Code or any other MCP client read and edit the documents you have open:

  {
    "mcpServers": {
      "picamd": {
        "command": "/Applications/PicaMD.app/Contents/Resources/picamd-mcp"
      }
    }
  }
  

Install

PicaMD requires macOS 27 or later on a Mac with Apple silicon. The Apple Intelligence provider also needs Apple Intelligence turned on in System Settings; the other providers don't.

1. Download the latest PicaMD-<version>.zip from Releases and move PicaMD.app to /Applications.
2. PicaMD isn't notarized yet, so macOS blocks the first launch. Open System Settings ▸ Privacy & Security, click Open Anyway next to the message about PicaMD and confirm. Or remove the quarantine flag before the first launch:

   xattr -dr com.apple.quarantine /Applications/PicaMD.app
   

Updates arrive through Sparkle.

Build from source

You need Xcode 27 or later and XcodeGen.

brew install xcodegen
git clone https://github.com/michiwickman/picamd.git
cd picamd
./build.sh              # build and install to /Applications
INSTALL=0 ./build.sh    # build only
./release.sh            # → dist/PicaMD-<version>.zip (writes the build number into project.yml)

Privacy

PicaMD has no telemetry and no server of its own. Documents stay where you save them. The update check fetches appcast.xml from this repository. The first Mermaid diagram downloads Mermaid from cdn.jsdelivr.net, and exported HTML files load KaTeX and Mermaid from the same CDN when opened. AI requests go only to the provider you choose, and only when you trigger them. Apple Intelligence runs on the Mac; Anthropic, OpenAI and custom providers receive the selected text over the network. The MCP server talks to local clients over stdio, and can see only the documents open in PicaMD.

Known limitations

• The app is ad-hoc signed, so the first launch needs the Open Anyway step above until the app is notarized.
• The Quick Look extension is included, but macOS only loads it for apps signed with a Developer ID.

Acknowledgements

swift-markdown, Sparkle, KaTeX (bundled, MIT, see PicaMD/Resources/katex/LICENSE) and Mermaid (downloaded the first time it's needed).

License

MIT. See LICENSE.