Job Opportunities API

About Us In partnership with  Sony and SBI  — two of Japan's largest companies — we are building the infrastructure to bring the world's assets on-chain:  Strium , a next-generation DeFi L1 powered by a fully on-chain orderbook exchange, and  Startale App , a consumer super-app. Distributed across Tokyo, New York, and Singapore; English-operating; built to a world-class standard. About the Role We are looking for a Senior Backend Engineer to take ownership of the backend systems powering StartaleApp and other products across the Startale ecosystem. This is a senior, hands-on engineering role for someone who can own complex backend systems end-to-end - from designing APIs and backend services, to building scalable data pipelines, managing databases, integrating blockchain infrastructure, and operating production systems under real-world load. We are looking for an engineer who thrives in a startup environment and is comfortable taking responsibility for any part of the backend stack depending on what the product needs. One month you may be building user-facing APIs, another month designing blockchain indexers, optimizing database performance, improving system reliability, or architecting entirely new backend services from scratch. Most importantly, we are looking for someone who has previously built and operated large-scale production systems serving real users at meaningful scale . You should have firsthand experience designing systems that handle high traffic, large datasets, reliability challenges, and the operational complexity that comes with running critical backend infrastructure in production. You should be excited by solving difficult engineering problems, building systems that scale, and owning critical infrastructure with a high degree of autonomy. You will take ownership of live production systems from your first weeks. This role assumes prior hands-on Web3 backend experience — we are not looking for someone to learn the Web3 side on the job. You will work closely with product, infrastructure, and protocol teams to build reliable systems that power seamless user experiences across both traditional and blockchain-based applications. Because our core product is a Web3 wallet, we highly value engineers who understand how decentralized applications work in practice — not just at the protocol level, but also from the perspective of real-world user interactions with wallets, DeFi protocols, and blockchain-based financial systems. Key Responsibilities Take ownership of backend architecture and implementation across multiple products within the Startale ecosystem. Design, build, and maintain scalable production APIs and backend services used by customer-facing applications. Build and operate high-performance distributed systems capable of serving large user bases and handling significant production traffic reliably. Design backend systems with strong focus on scalability, fault tolerance, reliability, and long-term maintainability . Build and maintain data pipelines, background workers, asynchronous processing systems, and event-driven architectures . Build and maintain blockchain integrations and indexing systems that ingest, process, and serve on-chain data to internal services and user-facing applications. Design efficient database schemas, optimize complex queries, and ensure long-term scalability of data storage systems. Work across both Web2 and Web3 backend infrastructure , integrating traditional backend systems with blockchain protocols and decentralized infrastructure. Diagnose and solve complex production issues, performance bottlenecks, reliability problems, and scaling challenges. Build systems with strong observability, monitoring, alerting, and operational tooling. Continuously improve backend architecture, deployment pipelines, system reliability, and engineering practices. Move quickly, make sound technical d