Senior Software Engineer - New Markets Japan

About the role

Alpaca, a US-headquartered brokerage infrastructure company, is looking for a Senior Software Engineer for its New Markets Japan team. The role is fully remote and requires fluent or business-level Japanese. You will design, build and maintain the systems that power millions of users, contribute to regional recruitment, mentor teammates, and take part in operational reliability during Japan business hours.

Key responsibilities

• Design highly scalable, mission-critical brokerage systems for the Japan market.
• Build and improve middle- and back-office systems, including gRPC and REST APIs and integrations with Japan vendors (JPX, JSCC, JASDEC, banks, identity verification).
• Help transform the core framework to support multiple languages, currencies and markets, with a focus on Japan-specific needs such as NISA, MyNumber, withholding tax and JP-GAAP accounting.
• Work with tech leads in other regions and coordinate in Japanese with regulators, vendors and partners, turning their requirements into technical specs.
• Troubleshoot incidents and bugs, and join on-call rotations during Japan business hours.

Required profile

• Business-level Japanese and business-level English.
• Proven experience designing complex financial systems, preferably with double-entry accounting.
• Understanding of accounting principles, ledgers and transaction reconciliation, and multi-currency financial applications.
• Familiarity with financial market regulations, with a preference for Japan experience (FIEA, FSA, JSDA, JIPF).
• Experience with financial APIs, market data and trade settlement.
• Ability to work independently in a fully remote, global team under pressure.

Required skills

• A statically typed language such as Go, Rust, Java, Kotlin, C# or C++.
• Domain-driven design and event-driven design.
• Nice to have: Go, experience with JPX, JSCC, JASDEC or NISA/iDeCo, and experience in a startup or fast-growing company.

What we offer

• Competitive salary and stock options.
• Health benefits.
• One-time home-office setup of USD 500 and a monthly USD 150 stipend via a Brex card.