Reader

Screen.Recording.2026-04-18.at.2.06.38.AM.mov

A macOS markdown reader and WYSIWYG editor. One surface: the markdown source is the rendered view — syntax marks stay visible as quiet tertiary-ink, so copy and paste round-trip losslessly as markdown. No preview pane, no export step.

Download the latest release

What it does

• Single-surface editing — markdown is rendered in place; **bold**, # headings, `code`, links, lists, quotes, rules, strikethrough all style as you type
• Markdown-fidelity clipboard — copy writes markdown; paste accepts markdown, HTML, or RTF and converts back to markdown
• Preview mode — ⌘⇧P hides the syntax marks for a clean read; source is preserved on return
• Classical typography — New York serif, 66-character measure, 1.4× leading, warm off-white page; grounded in Bringhurst, Butterick, Hochuli, Tufte, Warde
• Silent micro-typography — straight quotes become curly, -- becomes en-dash, --- becomes em-dash, ... becomes ellipsis; suppressed inside code spans
• Active format indicator — bold/italic/code/heading/list/quote buttons burn scarlet when the caret is inside that markup
• Dark mode — follows System Settings automatically via semantic colors
• Auto-update — Sparkle-powered, EdDSA-signed updates from GitHub Releases
• .md handler — registers for .md, .markdown, .mdown, .mkd, .mkdn via CFBundleDocumentTypes

Requirements

• macOS 13 (Ventura) or later
• Xcode 15 or later
• xcodegen: brew install xcodegen

Building

./scripts/build-app.sh --debug
open build/Debug/Reader.app

Or open in Xcode:

xcodegen generate
open Reader.xcodeproj

Installing

First launch: right-click → Open → Open (Gatekeeper warns on ad-hoc signed apps; subsequent updates install silently via Sparkle).

To make Reader the default markdown handler: ./scripts/build-app.sh --install, then Finder → Get Info on any .md file → Open With → Reader → Change All….

Releasing

./scripts/release.sh <version> "release notes"
git add appcast.xml && git commit -m "release <version>"
git tag v<version> && git push --tags
gh release create v<version> build/Reader-<version>.zip \
    --title "Reader <version>" --notes "…"

The EdDSA signing key lives in the macOS Keychain; the public half is in Resources/Info.plist (SUPublicEDKey). Sparkle will refuse any update that isn't signed by the matching private key.

Design docs

• Architecture Decision Records — load-bearing decisions: single-surface WYSIWYG, regex styler vs AST, AppKit over SwiftUI, Sparkle for updates
• Security review — threat model, findings, mitigations