Mira

Mira is a quiet Markdown editor for macOS, inspired by Typora's focused writing experience.

It is built with SwiftUI and a small AppKit text-editor bridge, keeping native macOS editing behavior while rendering a live Markdown preview.

Features

• Starts with an untitled empty Markdown document
• Opens the first document window at the largest visible desktop size by default
• Closes the untouched temporary document when opening an existing file
• Source, split, and preview modes
• Synchronized scrolling between editor and preview in split mode
• Markdown outline sidebar
• Focus mode for distraction-light writing
• Runtime language setting for English, Simplified Chinese, or system language
• Settings for pasted/local image insertion behavior
• Native NSTextView editing with undo and find support
• Toolbar and menu commands for headings, emphasis, links, lists, tables, and code blocks
• Automatic Markdown code fence completion when typing triple backticks
• Preview rendering for headings, paragraphs, quotes, lists, task lists, tables, code blocks, HTML blocks, local images, and remote images
• Remote image caching to avoid reloading images on every edit
• Clipboard image paste support
• Word, character, heading, and reading-time stats

Image Handling

Mira supports Markdown images from several sources:

![local absolute](/Users/name/Pictures/image.png)
![local relative](assets/image.png)
![remote](https://example.com/image.png)

Relative image paths are resolved from the current Markdown file's directory. Save the document first if you want relative image previews to work.

When pasting an image into the editor:

• Images copied from the system clipboard are saved as PNG files.
• Image files copied from Finder are copied into assets/ using their original bytes and extension.
• Pasted image files are saved beside the current Markdown file in an assets/ folder.
• If assets/ does not exist, Mira asks before creating it.
• The image insertion behavior can be changed in Settings.

Requirements

• macOS 14 or later
• Xcode 15 or later
• Swift 5.9 or later

Build And Run

Open Package.swift in Xcode, or build from Terminal:

swift build

To build and launch a local app bundle:

./script/build_and_run.sh

Package

To create a movable release app and distributable archive:

./script/package_app.sh

The script builds Mira.app, signs it ad-hoc by default, validates the bundle with codesign, and tries to create a DMG. If macOS disk image services are unavailable, it falls back to a zip archive.

For a Developer ID signed build, pass a signing identity:

SIGN_IDENTITY="Developer ID Application: Your Name (TEAMID)" ./script/package_app.sh

Public distribution outside your own Mac generally requires Developer ID signing and notarization.

Project Layout

Sources/Mira/App        App entry point and commands
Sources/Mira/Models     Document, block, command, and sync models
Sources/Mira/Support    Markdown parsing and asset helpers
Sources/Mira/Views      Editor, preview, toolbar, outline, and status UI
script                  Local run and packaging scripts

License

Mira is released under the MIT License.