showmd - Markdown was never meant to be previewed plain text

Hey PH! 👋 You might know me from Holdor (my first side project in years launched last month here on PH) — after that launch I dove deeper into developer tooling, and one daily frustration kept nagging me. I work with Markdown files all day. CLAUDE.md, AGENTS.md, README.md — they're everywhere now. But every time I hit Space in Finder to Quick Look one, I'd get a wall of raw text. Hashes, dashes, angle brackets. Unreadable. So I did some research. There are a few tools that handle basic Markdown formatting, sure. But none of them understand how Markdown is actually used today — especially in agentic AI workflows. YAML frontmatter? Rendered as noise. Custom XML tags like , , ? Just raw angle brackets. That's the gap I built showmd for. It's a free, native macOS Quick Look extension. Press Space on any .md file and get an instant, beautifully rendered preview — with frontmatter parsed into a collapsible metadata table, 20+ agentic AI XML tags styled as labeled blocks, syntax highlighting for 190+ languages, KaTeX math, Mermaid diagrams, and full GitHub Flavored Markdown support. All offline, all bundled, zero config. Since launching so many side projects again is fun, I thought: let's group everything together under my new side project brand yetanother.one — which should indicate: yes, I have lots of ideas, and yes... those happen mostly at night. Hope you like it! Let me know what I should build next? Spoiler: I'm currently working on something completely different — a new Android launcher.