Sign up
All challenges
Most candidates spend 5–9 hours; take what you need.

Multi-Channel Alert Delivery

Design a reliable, multi-channel notification layer for time-sensitive price and portfolio alerts.

The problem

A price alert is only useful if the user actually sees it in time. Right now, one delivery channel means one point of failure — an email that lands in spam, a provider outage, a missed notification, and the alert might as well not have fired.

The interesting problem isn't "send an email" — it's designing delivery that's reliable, doesn't double-notify, degrades gracefully, and tells you when it failed.

What to deliver

  • A design (and prototype, if you have time) for a multi-channel alert delivery layer — at least two channels (e.g. email + push, or email + webhook), with a clear fallback strategy if the primary channel fails.
  • An idempotency/dedup approach so a flaky retry never double-fires the same alert to a user.
  • A way to detect and surface delivery failures, not just fire-and-forget.
  • A note on how your design scales when thousands of alerts can fire in the same few minutes (e.g. a volatile market open).

What a good submission looks like

  • Treats "the notification silently failed" as a monitored, first-class failure mode.
  • Has genuine fallback logic — not just "try channel A, then channel B" with no coordination.
  • Thinks about burst load, not just steady-state single alerts.

We're evaluating

Delivery reliabilityIdempotency & dedupChannel fallback designFailure visibility

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-alert-delivery.zip.
  4. Email it to us — the button below pre-fills the subject and a template.