Responsibilities:

• Design and iterate architecture for core credit/debit card payment systems, covering full card lifecycle (account opening, binding, activation, cancellation) and key modules (authorization, clearing & settlement, reconciliation).
• Build and implement integrations with major card processors (VISA, MasterCard, etc.) through payment gateways.
• Develop high‑concurrency, low‑latency transaction solutions capable of handling millions of transactions per second.
• Design anti‑fraud engines and transaction risk models; integrate real‑time risk control systems (device fingerprinting, behavioral analysis).
• Collaborate with product teams to deliver innovative payment features (installments, pre‑authorization, one‑click, contactless).
• Establish robust data security, logging, and audit systems to ensure traceability, abnormal transaction monitoring, and risk alerts.

Requirements:

• Bachelor’s degree or above in Computer Science, Software Engineering, IT, or related field.
• 3–5 years of Java backend development experience, with at least 2 years in Payment/Fintech/Card projects.
• Hands‑on experience in developing core systems for credit cards, debit cards, or third‑party payment platforms preferred.
• Proficient in Java with strong knowledge of Spring Boot, Spring Cloud, MyBatis, and mainstream frameworks.
• Solid background in microservices architecture and distributed system design.
• Proven ability to build high‑concurrency, high‑availability systems; familiar with Redis, Kafka, RocketMQ, MySQL, Elasticsearch, and related middleware.