Worked designs
This folder has no README. Everything inside it is listed below.
Notes
- Worked Design — URL Shortener 5 The "warm-up" system design question. It looks trivial; the depth is in code generation, the read path at scale, and analytics.
- Worked Design — Distributed Rate Limiter 6 A focused design question that tests algorithm knowledge, distributed-state handling, and failure-mode thinking.
- Worked Design — Notification / Fan-out Service 6 "Design a system that sends notifications" — email, push, SMS, in-app.
- Worked Design — News Feed / Timeline 6 The canonical "design Twitter/Instagram feed" question.
- Worked Design — Chat & Presence 6 "Design a chat system" (Slack/WhatsApp-style).
- Worked Design — Distributed Cache 7 "Design a distributed cache" (a Redis/Memcached-class system).
- Worked Design — Distributed Job Scheduler 7 "Design a system that runs scheduled and background jobs" (cron-as-a-service / a task queue platform).
- Worked Design — Idempotent Payment Flow 7 "Design a payment processing flow." The whole question is correctness under failure — never double-charge, never lose a payment, stay consistent across your…
- Worked Design — LLM usage metering 4 "Design a system that records LLM usage (tokens, model, latency) per customer, shows it on dashboards, enforces budgets, and feeds billing." It looks like…
- Worked Design — File and image processing pipeline 4 "Users upload images and documents; we scan them for malware, make thumbnails and previews, and show them in the app.