Biqing Cao

Financial Team

• Worked as Tech Lead for a 7-person team in team, improving the e-commerce purchasing experience by designing and implementing diverse Spring Boot payment services such as credit card, PayPal, and gift card processing. Responsibilities included collaborating with PMs for requirements, designing systems, delegating tasks, and participating in solution delivery.
• Worked closely with Chase Paymentech to achieve PCI compliance for the company, focusing on data security in storage and transmission while integrating credit card transaction processing.
• Collaborated with DevOps to create separate PCI clusters for financial services, ensuring transactional data security and isolation from other services.
• Developed a seller transaction dashboard, addressing complex calculations including partial order refunds, and adapting to evolving requirements through communication with stakeholders.

Search and Recommendation

• Prioritize and implement high-impact strategies for SEO, leading to a collaborative project with Front End and Infra teams. Resulted in a 50% boost in impressions (2M to 3M) over 3 months.
• Applied NLP techniques like spell correction, query expansion, and intention normalization to query processing, enhancing relevance ranking by 20% and broadening ETL traffic coverage.
• Conducted performance analysis of Redis and MongoDB to optimize support for 1M active users, 5M guest users, and 12M daily updated products.
• Reduced pub/sub consumption by 60% by message filtering, topic optimization, batch processing, and collaboration with upstream publishers, mitigating CPU usage spikes.
• Enhanced API performance by 50%, scaling up to 65k TPS through Nginx refinement, caching strategies, MongoDB optimization, and collaborative pressure testing and tuning with DevOps.

• Designed a real-time monitoring system, reducing operational workload by 20% by integrating internal metrics and minimizing support tickets.
• Developed multiple payment methods for API services with customized features that meet security standards, ensuring seamless customer payment experiences.
• Implemented secure PII data transfer through XML processing, enabling safe client payment transactions.
• Provided onboarding assistance and ongoing support to plugin clients, resulting in successful integration and adoption of API services.