Backend Developer at Bjak in Tokyo, Tokyo, JP

About BJAK

The original mission of BJAK is we believe people deserve smarter ways to plan, save and grow their money. This is the origin of our name.

Started in 2019, we built the first mobile-first, insurance platform, enabling insurance to be accessible online by millions in the region. Today, its the leading insurance platform in Southeast Asia.

Today, we are expanding ways to help people in the region — this includes spending, saving, investing, exchanging, travelling, and more. Our mission is help people get more from their money every day.

We have teams working around the world, with over 20 nationalities from our offices and remotely, who truly enjoys their work. We are looking for the most talented and driven people we can find. We are looking for people who work for their passion, not counting hours. Who loves building great next-generation products, not status quo. Who cares about redefining how everyone around us can get the best financial applications, not for an exclusive few.

If you're this person, we'd love to talk to you.

The Role

We are looking for backend engineers to build the core systems behind BJAK's AI Neobank app.

This role is for engineers who can build reliable APIs, workflows and financial product infrastructure that can scale across markets, partners and millions of users.

What You'll Own

• Build backend services and APIs for onboarding, accounts, payments, cards, transfers, rewards, travel, FX, KYC and risk flows.
• Design reliable systems that can support real customer transactions, operational workflows and future financial products.
• Integrate with internal systems, financial partners, payment providers, AI services and third-party platforms.
• Own backend quality across reliability, security, latency, observability, data integrity and incident handling.
• Work with product, frontend, mobile and AI teams to launch features quickly and safely.
• Improve existing systems by simplifying flows, removing manual work and automating repeatable processes.

What We're Looking For

• Strong backend engineering experience in production systems.
• Good understanding of APIs, databases, authentication, authorization, queues, jobs, events and integrations.
• Experience building services used by real customers or internal operations at meaningful scale.
• Strong debugging, reliability, security and data quality mindset.
• Able to make practical trade-offs between speed, correctness, scalability and maintainability.
• Fintech, payments, banking, wallet, KYC, fraud or risk experience is a strong plus, but not required if fundamentals are strong.

This Role Is Not For

• Engineers who only want isolated backend tasks.
• People who ignore security, data consistency, monitoring or operational risk.
• Developers who cannot work with fast-changing product requirements.
• Candidates who talk about scale but have not handled production systems.
• People who exaggerate impact without being clear on ownership.

The Bar

We are looking for engineers with real technology career highlights. A strong highlight is not just working at a famous company. A strong highlight means you personally helped build, ship or scale a serious product, platform or system.

Location

This role is based in Japan. This is a hybrid role. You are expected to work from our Japan office at least 3 days per week.

Language

English is our main working language across global teams. Strong English communication is required.

Interview Process

Our process is designed to move fast:

1. Online assessment or practical task

2. Technical interview

3. CEO / final round

For strong candidates, we aim to complete the process and make an offer within 1 week from the start of the interview process. Candidates who complete assessments quickly will be prioritized.