What API and data model would support a new Messenger workflow for teen users

Problem Statement Description

Product context: Meta is a social technology company; its products include Facebook, Instagram, WhatsApp, Messenger, Threads, Quest, creator tools, and ads.

Meta is exploring a new Messenger workflow designed specifically for teen users. In this interview, you are asked to define the API and data model that would support the workflow end to end, with attention to how teens initiate, manage, and participate in messaging experiences while maintaining safety, privacy, and reliability at Messenger scale.

Assume the workflow may involve teen-specific interaction rules, social graph constraints, consent or guardian-related controls, content and contact safety, notifications, and cross-surface Messenger experiences. Your task is not to design the full consumer UI, but to reason through the backend product architecture required to make the experience work consistently across clients.

You should think like a Technical PM working with engineering, privacy, integrity, legal, data, and product teams. The discussion should clarify requirements, define the core entities and relationships, outline APIs and permissions, and identify how the system would be monitored, rolled out, and evolved.

The experience should consider:

- The primary teen user journeys the API must support, including onboarding, discovery, messaging, controls, and reporting or blocking flows

- Core data objects, relationships, state transitions, and ownership boundaries across users, conversations, permissions, safety settings, and events

- API contracts for client actions, backend services, eligibility checks, policy enforcement, and error handling

- Privacy, age-appropriate design, data minimization, consent, retention, and access-control requirements

- Safety mechanisms such as contact restrictions, abuse prevention, moderation signals, escalation paths, and auditability

- Reliability, latency, idempotency, offline behavior, synchronization across devices, and backward compatibility with existing Messenger clients

- Instrumentation for product health, safety outcomes, policy compliance, debugging, and experimentation

- Rollout strategy, feature gating, migration considerations, observability, incident response, and rollback plans

The goal is to evaluate how you translate a teen-focused Messenger product workflow into a technically sound platform design that balances product usability, safety at scale, privacy obligations, and Meta’s existing messaging ecosystem constraints.