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Mobile Push Notification Infrastructure

Design and prototype push notifications for our React Native (Expo) app — a real, currently-missing piece of the mobile product.

The problem

Our Expo-based mobile app ships without push notifications — it was explicitly deferred out of v1. Meanwhile, the backend already produces real-time events (a price alert firing, a portfolio move) that have no way to reach a user who isn't staring at the app.

Building this properly means handling device token registration and expiry, choosing between silent and user-visible pushes, and designing the backend-to-device fan-out without turning every push into a battery drain or a notification-fatigue problem.

What to deliver

  • A design (and prototype, if you have an Expo dev environment) for push notification infrastructure: device token registration/refresh, a backend event-to-push pipeline, and delivery via Expo's push service (or your alternative of choice).
  • A decision on silent vs. user-visible push for different event types, with reasoning.
  • A plan for token lifecycle — expired tokens, reinstalls, multiple devices per user.
  • Notes on how this interacts with the alert-delivery problem above, if you attempt both — they overlap.

What a good submission looks like

  • Handles token expiry and device churn as the normal case, not an edge case.
  • Has a real opinion on notification frequency and user fatigue, not just "send everything."
  • Understands the tradeoffs between push reliability and battery/OS-level throttling.

We're evaluating

Token lifecycle managementBackend-to-device wiringDelivery guaranteesBattery/UX tradeoffs

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