System Design Interview Prep on One Desktop (Not 8 YouTube Tabs)

PrepOS for system design: ByteByteGo feed, Excalidraw, notes, AI Chat, and Capture→AI for architecture diagrams — in one Electron window.

System design prep is tab-heavy: ByteByteGo or Educative, Excalidraw for boxes-and-arrows, a doc of tradeoffs, and ChatGPT for “is this CQRS overkill?” PrepOS keeps reading, drawing, and questioning in one shell.

Apps to pin for design week

  • Feed reader — system design tagged articles (ByteByteGo, etc.).
  • Excalidraw web app — URL bar whiteboard in a window.
  • Notes — paste template: requirements, estimates, APIs, failure modes.
  • AI Chat — paste or Capture→AI a diagram screenshot for review.

Capture→AI for whiteboards

Sketch on Excalidraw or a PDF slide, select the region with Cmd+Shift+A, and ask Claude or GPT-4o: “What did I miss for scale?” or “Where is my single point of failure?” Faster than describing the diagram in text.

Pair with the 7-day sprint

Day 5 of the built-in sprint nudges design fundamentals before mock day. Use focus lock so “just one Hacker News article” does not eat the evening.

Ready to try Capture→AI and the 7-day sprint? Download the latest PrepOS build — free, open-source, macOS / Windows / Linux.