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Full-Stack / Real-Time Product

Build or extend a real-time UI surface — a live dashboard, ticking watchlist, or similar — under concurrent load.

The problem

A dashboard that looks great with 5 rows updating once a minute is a different engineering problem from one with hundreds of rows updating multiple times a second across thousands of concurrent viewers.

The failure modes that matter are: UI thrash from over-rendering, stale state after a reconnect, and a server fan-out design that doesn't fall over under load.

What to deliver

  • A real-time UI surface (a live dashboard, ticking watchlist, order-book-style view — your choice) backed by a data source that updates continuously.
  • A server-side or client-side architecture that scales to many concurrent viewers without re-fetching everything per client.
  • Deliberate handling of reconnects, out-of-order updates, and render performance (no visible jank as updates arrive).
  • A short note on where your design would break first at 10x the load, and what you'd change.

What a good submission looks like

  • Treats reconnect/resync as a first-class case, not an afterthought.
  • Shows an actual understanding of render cost — batching, memoization, virtualization where it matters.
  • Has a clear opinion on push vs. poll and why, for this specific use case.

We're evaluating

ArchitectureReal-time state managementPerformance under loadUX polish

How to submit

  1. Build your solution, using any tools or stack you prefer.
  2. Write up your thinking — decisions made, tradeoffs, what you'd do with more time.
  3. Zip your code + write-up, name it yourname-realtime-product.zip.
  4. Email it to us — the button below pre-fills the subject and a template.