Backend Engineer - Fintech APIs & Scale (Remote Spain)

BJAK; España; Presencial; USD 69.000 - 104.000; Jornada completa

Descripción de la vacante

BJAK is hiring backend engineers to build the core systems behind BJAK's AI Neobank app. You will create reliable APIs and backend services that scale across markets and millions of users, handling onboarding, accounts, payments, cards, transfers, KYC and risk flows.

You will integrate with internal systems, financial partners, payment providers, AI services and third-party platforms, owning backend quality across reliability, security, latency, observability and data integrity.

Formación

• 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 balance speed, correctness, scalability and maintainability in design decisions.
• Fintech, payments, banking, wallet, KYC, fraud or risk experience is a strong plus, but not required if fundamentals are strong.

Responsabilidades

• Build backend services and APIs for onboarding, accounts, payments, cards, transfers, rewards, travel, FX, KYC and risk flows.
• Design reliable systems that 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.

Conocimientos

APIs & Databases

Security & Reliability

Performance & Scalability

Fintech Knowledge

System Integration

Descripción del empleo

BJAK is hiring backend engineers to build the core systems behind BJAK's AI Neobank app. You will create reliable APIs and backend services that scale across markets and millions of users, handling onboarding, accounts, payments, cards, transfers, KYC and risk flows.

You will integrate with internal systems, financial partners, payment providers, AI services and third-party platforms, owning backend quality across reliability, security, latency, observability and data integrity.