Fiat Developer

About ABFinance ABFinance is a US-based firm building and enabling digital finance for the future. Their vision is to create a full financial ecosystem where digital assets, traditional finance, and everyday money management live in one seamless experience, made available to everyone. Founded by a team of innovators, traders, and compliance professionals, ABFinance's mission is to bring the emerging world of digital assets to everyone. Their flagship product is a secure, regulated crypto exchange building trading tools for both retail and institutional clients—including spot trading and yield generation products with a focus on compliance and security. Role Overview We are looking for a Java Developer to build and enhance backend services that power secure, reliable, and scalable systems. In this role, you will work closely with product and business teams to deliver high-quality features, optimize system architecture, and solve complex technical challenges. You will be expected to understand end-to-end product workflows and use technology to drive continuous business growth. Responsibilities Take end-to-end ownership of ABFinance’s existing fiat/payment backend, ensuring stable operation and fast iteration during platform scaling. Participate in backend service development, ensuring system security and high availability. Communicate with stakeholders to understand requirements, support business development, and drive service launches. Continuously optimize system architecture and tackle key technical challenges. Understand product workflows and leverage technology to drive business growth. Requirements 5–10 years of backend engineering experience in production systems; strong preference for candidates who have owned and evolved an existing platform (not only built new services). Hands-on experience building or operating fiat payment systems such as on/off-ramps, bank transfers, card payments, ACH/wire/SEPA/FPS/PayNow, or local rails. Familiar with payment lifecycle: authorization → capture/settlement → refunds/chargebacks → reconciliation. Practical knowledge of risk controls & compliance touchpoints, e.g., KYC/AML hooks, fraud/rule engines, transaction limits, sanctions screening, audit trails. Experience with ledgering / balance accounting and reconciliation pipelines (especially for high-volume flows). Lead a structured technical handover from BB engineering, including architecture understanding, codebase absorption, and operational runbooks. Understanding of common Java design patterns and the ability to apply them appropriately. Proficiency with mainstream Java frameworks and tools, such as Spring Boot, Spring Cloud, Spring MVC, etc. Familiarity with database principles and optimization strategies; strong SQL skills; understanding of caching, messaging queues, and related technologies. Experience integrating with PSPs / banks (e.g., Stripe/Adyen/Checkout.com/local banks or processors) is a plus. Understanding of PCI-adjacent security practices and sensitive data handling is a plus. Strong sense of ownership for software products, with good communication skills and excellent teamwork. Fluency in English and Chinese (Mandarin) required