About our product We are building the first seedless Bitcoin wallet: secure, simple, and fully recoverable. No seed phrases, no hardware hassle, no custodial risk. We use Bitcoin-native MPC to combine sovereign-grade security with everyday usability, so customers can set up in seconds and trust their Bitcoin for life. We’re looking for a staff/ founding backend engineer to help us build the foundations of a smooth, reliable, and secure wallet experience, applied to the future of Bitcoin. What you’ll do ● Design and build low-latency APIs and realtime services that make sends, swaps, and approvals feel instant. ● Own backend integrations with partners (e.g., Turnkey, OneBalance), including secure webhooks, retries, and idempotent flows. ● Implement a policy engine for approvals, caps, timelocks, and joint accounts. ● Build a resilient ledger and state machine for money movement with full auditability. ● Deliver push-based updates (websockets/SSE) for a snappy mobile UX. ● Define and uphold performance budgets: p95 <150ms for core APIs, near-realtime event streaming. ● Instrument, monitor, and debug production systems with OpenTelemetry, structured logs, and metrics. ● Collaborate closely with product and frontend engineers to make the UX buttery-smooth. What we’re looking for ● 5+ years building backend systems that serve consumer-facing products at scale. ● Deep skill in at least one systems language (TypeScript/Node, Go, Rust, Kotlin) ● Someone who can lead and design end to end architecture ● Strong sense of ownership and leadership skills ● Strong command of async I/O, queues, retries, and state machines. ● Experience designing idempotent money movement flows (or equivalent critical workflows). ● Database fluency (Postgres, Redis) and data modeling for consistency (sagas, outbox, dedupe). ● Comfort with API design, schema versioning, pagination, and event streaming. ● Solid instincts for security, privacy, and compliance in sensitive domains. Bonus ● Exposure to fintech/payments (ledgers, reconciliation, card rails, treasury systems). ● Experience with crypto custody or MPC services (e.g., Turnkey, Privy, onebalance.io) ● Understanding of Bitcoin UTXO basics or stablecoin mechanics. ● Prior work on policy/rules engines or joint/multi-party account flows ● Strong debugging chops: tracing, profiling, and fixing performance bottlenecks. Requirements ● Someone who can work full time from our office in Hyderabad, India
About the Role We’re looking for a Senior Mobile App Developer to join our core team in Hyderabad. You’ll own the design and implementation of high-performance mobile experiences for our flagship app, working closely with backend engineers (TypeScript, Rust/Go) and product designers. You’ll help define our mobile architecture, drive performance and reliability improvements, and build features that make crypto and fintech simple, secure, and delightful. Responsibilities Design, build, and maintain cross-platform mobile applications using React Native (Flutter experience is a plus). Collaborate with backend and design teams to deliver clean, performant, and scalable mobile experiences. Integrate REST APIs and handle data persistence, caching, and offline-first logic. Develop and maintain native modules (Swift/Kotlin) where necessary for performance-critical paths. Debug, profile, and optimize performance across iOS and Android. Participate in code reviews, architecture discussions, and Agile development cycles. Ensure best practices for security, data privacy, and smooth app deployment to the App Store and Google Play Requirements 3+ years of professional experience in mobile app development. Proven experience shipping apps to App Store or Google Play. Strong proficiency in React Native (preferred) or Flutter, with deep understanding of cross-platform performance patterns. Experience integrating REST APIs, managing app state, and handling persistence (AsyncStorage, SQLite, or similar). Solid understanding of mobile architecture, debugging, and troubleshooting complex issues. Excellent communication and collaboration skills in an Agile team environment. Nice-to-Have Experience with FinTech or Crypto applications. Familiarity with mobile security best practices, such as key management and biometric authentication. Experience writing unit/integration tests and using CI/CD pipelines for mobile deployments. Knowledge of TypeScript and comfort collaborating with backend systems built in TypeScript, Rust, or Go Why Join Us Build at the intersection of crypto, fintech, and mobile UX. Collaborate with a world-class team in a fast-moving, high-ownership environment. Work on challenging technical problems with meaningful real-world impact. Location Hyderabad, India (On-site preferred)