DOOM MCP vs Quarkdown

Chris Nager built a fully playable DOOM that runs as an MCP (Model Context Protocol) app, rendering inline inside Claude and ChatGPT without a separate browser tab. The architecture uses two MCP tools — create_doom_session for inline-capable hosts and get_doom_launch_url as a browser fallback — combined with cloudflare/doom-wasm for the game runtime and a signed token system that maintains session state across both surfaces. The result is the same session whether you're playing inline or in a tab. The key technical challenge was avoiding iframe and CSP (Content Security Policy) issues. Rather than embedding a browser page inside the MCP iframe, the DOOM canvas runs directly inside the host's iframe — a subtle but critical distinction that resolved a class of rendering and input-handling bugs. The final implementation is intentionally stripped down: no save/load, no persistence adapters, just stable playable DOOM. Beyond the novelty, this project is a concrete demonstration that MCP apps are interactive surfaces, not just tool-calling JSON endpoints. The progressive enhancement pattern — same signed-token foundation serving both inline and browser modes — is a reusable architecture for any game or interactive experience that wants to live inside an AI assistant. Nager open-sourced the implementation and the blog post is a detailed technical breakdown.

Quarkdown is an open-source typesetting system built on Markdown that eliminates the need for separate tools like LaTeX, Notion, GitBook, or Beamer. Write once in a single extended Markdown syntax and compile to paged PDFs, knowledge bases, documentation sites, or interactive presentations. The system includes Turing-complete scripting that lets you define reusable functions, avoiding repetitive formatting work across large document sets. A live reactive preview updates as you type, making the editing loop feel modern rather than the traditional LaTeX compile-and-pray cycle. Maintained by Giorgio Garofalo under GPL-3.0, Quarkdown hit 201 points on Hacker News this week and is positioning itself as a serious unified alternative to the fragmented academic and developer document toolchain. Not AI-native, but exactly the kind of leverage tool that saves hours every week for anyone writing technical docs, research papers, or slide decks.