Build a Content Moderation Pipeline Premium
Design a content moderation system that uses ML classifiers to automatically detect policy violations in text, images, and video, routes borderline cases to human reviewers, and minimizes both over-removal and under-removal.
Build a Distributed Tracing System Premium
Design a tracing platform that stitches spans across 50+ microservices into a single request trace, stores billions of spans per day, and lets engineers query any trace by ID in under 1 second.
Build an Event Sourcing and CQRS Audit Trail Premium
Design an event-sourced system where every state change is stored as an immutable event, supports replaying 3 years of history to reconstruct any past state, and separates read and write models for query performance.
Build an OAuth 2.0 Authorization Server Premium
Design an OAuth 2.0 authorization server that supports PKCE for public clients, implements refresh token rotation to detect theft, and provides a token revocation endpoint that propagates across all resource servers within seconds.
Build a Self-Healing Service Mesh Premium
Design a service mesh that continuously monitors the health of every service instance, automatically reroutes traffic away from degraded nodes, and triggers remediation actions without human intervention.
Build WhatsApp Message Delivery with Offline Queuing Premium
Design an end-to-end encrypted messaging system that delivers messages to online users in under 100ms, queues messages durably for offline users, and guarantees delivery exactly once when they reconnect.