Strengthening Backend Fundamentals: Distributed Service Architecture and Personal Growth

Li Yanpeng, chief architect of the product center at YiBao Pay, begins with a brief personal introduction, describing his experience at Citibank, Oracle, Reuters, and Sina Weibo, where he worked on education systems, foreign exchange trading platforms, and video services.

He then explains his current responsibilities at YiBao Pay, focusing on core system construction and maintenance (transactions, payments, channels, merchant platform), technical standards, and the financial industry's critical fund‑level firewall.

The core of the presentation is the distributed service architecture. Li outlines six primary goals: high availability, high performance, scalability, extensibility, security, and consistency. He discusses how YiBao Pay achieves four‑nine (99.99%) availability through architecture reviews, design reviews, and technical reviews, and how a "divide‑and‑conquer" approach improves throughput while introducing consistency challenges.

Scalability is achieved via horizontal expansion—sharding databases, partitioning caches, and using message‑queue smoothing. Security is addressed through five objectives (leak prevention, tampering prevention, repudiation prevention, eavesdropping prevention, and MITM protection) implemented with encryption, digital signatures, and mutual TLS.

Extensibility is distinguished from scalability; it refers to the system’s ability to evolve quickly to meet new market demands, often realized through plug‑in mechanisms.

Li recommends three books for deeper study: "Billion‑Level Traffic Site Architecture Core Technology" (high concurrency and availability), "Distributed Service Architecture Principles, Design and Practice" (micro‑services, consistency, APM, containerization, CI/CD), and "Large‑Scale Website Core Technology" (fundamental concepts).

He then shifts to "how to cultivate technical inner skills". He proposes evaluating a candidate’s breadth (various technologies and experiences), depth (mastery of specific areas such as Java GC or RDBMS indexing), and height (purpose and future relevance of the technology).

He outlines four themes for building inner skills: operating systems, algorithms & data structures, high‑concurrency services, and big data. He emphasizes understanding OS fundamentals (CPU, memory, disk, network I/O) to estimate throughput and latency, and mastering algorithms (including advanced topics like dynamic programming) to demonstrate problem‑solving ability.

He also discusses the importance of a "goal methodology"—defining clear objectives, principles (what not to do), methods (weighing trade‑offs), and outcomes—to ensure that architectural decisions are purposeful and cost‑effective.

Finally, he shares four personal principles for "inner work": reliability & intelligence, boldness with optimism, decisive action (persist or move on), and effective communication through empathy and self‑reflection.

The session concludes with a Q&A where Li answers audience questions about self‑learning for junior iOS developers, the value of backend experience for client developers, and career considerations between frontend and backend roles.