• Designing and owning core backend architecture in Rust (async-first) • Defining service boundaries, data ownership, and evolution strategy • Designing scalable APIs (REST and/or GraphQL) for mobile and web clients • Modeling and operating PostgreSQL as a long-term source of truth • Architecting real-time systems (feeds, messaging, event-driven workflows) • Making tradeoffs around consistency, latency, and scalability • Working with DevOps while retaining backend architectural authority • Reviewing critical code paths and preventing premature complexity • Helping shape the backend team as the company grows