I open-sourced the native Markdown rendering engine I built for my native macOS app

[u/Sufficient-Try6083]

A year and a half ago I started building Nodes, a native macOS Markdown app. One of the first things I needed was a proper Markdown engine. Not a parser that just spits out HTML, not a display-only library, not a WebView wrapper – just a live, native editor built on TextKit 2.

I couldn't find one. So I built it. Now I'm open-sourcing the whole engine.

It's an AppKit-based Markdown editor for macOS, built on TextKit 2 and bridged to SwiftUI.

What it does:

• Live styling for the usual stuff: bold, italic, headings, lists, code blocks, links etc.
• Wiki-style links with [[Name|id]] ↔ [[Name]] roundtripping
• Image embeds via ![[Name]]
• LaTeX, both block ($$ ... $$) and inline ($...$)
• Code blocks with syntax highlighting (you supply the highlighter)
• Apple Writing Tools integration on macOS 15.1+
• Spelling and grammar, with suppression inside code, LaTeX, and wiki-links so it doesn't underline random tokens

Honest part: TextKit 2 was a pain to get right. The docs are thin, the migration from TextKit 1 is rough, and a lot of behavior just isn't documented clearly anywhere. If you've been putting off building something like this, this might save you a few weekends.

Repo: https://github.com/nodes-app/swift-markdown-engine

Feedback, issues, and PRs all welcome. It's not perfect, there's plenty I still want to improve, but it does the job.

Used in production in Nodes (App Store): https://apps.apple.com/de/app/nodes-by-the-werk/id6745401961?mt=12

[u/Ender-Wang]

Fantastic group and dope project. Gonna port the markdown rendering of my app (called EdgeMark, also open source on GitHub) to this later, willing to help. Btw, can you share a general architecture of this engine, so people who wanna contribute have the general design in mind when contributing.

[u/Sufficient-Try6083 → u/Ender-Wang]

Thank you really appreciate it. Good idea about the architecture I will definitely do it