md.too

A minimalist Markdown viewer for macOS and iOS. Read-only, native, zero third-party dependencies.

What it does

• Open a .md file and see it rendered.
• Select text, copy it, scroll. Code blocks and tables have a one-click copy button.
• macOS Quick Look extension renders .md in Finder's preview pane and on spacebar peek.
• Syntax highlighting for about 40 languages (Swift, C/C++/C#/Objective-C, Java, Kotlin, Scala, JS/TS, Python, Rust, Go, Ruby, PHP, Dart, Lua, Perl, R, Julia, Haskell, OCaml, F#, Elixir, Clojure, Groovy, SQL, GraphQL, Dockerfile, Makefile, TOML, INI, YAML, JSON, XML, HTML, CSS, Bash, PowerShell, Markdown).
• GitHub-style task lists (- [ ] / - [x]).
• Tiny LaTeX subset in $…$ / $$…$$: Greek letters, super/subscripts, common operators, simple fractions.
• Export the rendered document to PDF (paginated, with images embedded).

See EXAMPLE.md for a single document that exercises every supported feature.

What it doesn't do

No editor, no live edit/preview split, no autosave. No HTML or WKWebView. No file tree, tabs, or command palette. No app-level themes (light/dark follows the system, or pick one explicitly). No third-party packages — pure Swift + AppKit/UIKit/SwiftUI.

For context: the most popular JavaScript Markdown library, marked, reports about 636 transitive dependencies and roughly 38,980 lines of code on its public dependency graph. The md.too app is a few Swift files with no dependencies. Every package you do not pull in is a supply-chain risk you do not inherit.

Download

Signed and notarized macOS .dmg is published as a GitHub Release on each tagged version:

Latest release

iOS app is in App Store review.

Build from source

Open md.too.xcodeproj in Xcode 15+ and pick a scheme:

• md.too macOS — the macOS app (Quick Look extension is bundled automatically).
• md.too iOS — the iOS / iPadOS app.
• md.too QuickLook — the Quick Look extension on its own; normally not needed.

Or from the command line:

xcodebuild -project md.too.xcodeproj -scheme "md.too macOS" build
xcodebuild -project md.too.xcodeproj -scheme "md.too iOS" \
  -destination "generic/platform=iOS Simulator" build

The project ships with no DEVELOPMENT_TEAM set, so a fresh clone builds with ad-hoc ("Sign to Run Locally") signing — no Apple Developer account required for local development. To override locally, drop a one-line Local.xcconfig next to Base.xcconfig containing LOCAL_DEVELOPMENT_TEAM = YOURTEAMID; it's gitignored.

Layout

Four Swift files:

• Markdown.swift — parser, SwiftUI views, themes, native text.
• Highlight.swift — syntax highlighter.
• PDFRenderer.swift — paginated PDF export with embedded images. macOS + iOS app targets only.
• QuickLook.swift — Quick Look extension principal class. macOS Quick Look target only.

Three Info-*.plist files cover document-type and Quick Look extension configuration that flat build settings can't express; entitlements files describe the sandbox for each target. Base.xcconfig includes a committed version.xcconfig and an optional gitignored Local.xcconfig.

Privacy

Privacy policy — short version: the app collects nothing, stores nothing, transmits nothing. The only network requests are HTTPS image fetches for inline images you reference by URL in your own Markdown.

License

MIT.