M
Marked QL
Instant Markdown preview in macOS Quick Look with rich rendering and Apex engine.
macOS 13+Apex Markdown EngineMath & Diagram SupportSyntax HighlightingInstant Spacebar Preview
Opportunity score
45/100
A well-executed niche utility with limited revenue potential but strong retention and low distribution friction.
Founder verdict
MAYBE
A polished niche tool with low revenue ceiling but strategic value as a feeder product.
What is Marked QL?
Marked QL is a $9.99 one-time purchase macOS utility that registers as a Quick Look generator for Markdown files. It leverages the Apex unified Markdown processor to render CommonMark, GFM, MultiMarkdown, Kramdown, and extensions including math (MathJax), diagrams (Mermaid), and syntax highlighting directly in Finder previews. The app stands alone but also integrates with Marked 3, Brett Terpstra’s full-featured Markdown preview app. It addresses a frequent pain point for Mac-based developers and writers who want a quick, fully styled preview without opening a dedicated application. The website emphasizes simplicity, power, and seamless macOS integration, appealing to both existing Marked customers and new users seeking a lightweight solution.
Get the full Marked QL playbook
The complete reverse-engineering — what to copy, what to avoid, and exactly what to build instead.
- Full opportunity score across 8 dimensions
- The real problem & why customers pay
- Why it's winning — with evidence
- Complete business reverse-engineering
- Competitive advantages & moat analysis
- Weaknesses, risks & what to avoid
- Clone strategy — what to build instead
- Week-by-week MVP roadmap
- Recommended technical stack
- Founder verdict & highest-leverage move