Master the Core Skills Every Backend Engineer Needs

Introduction

Li Yanpeng, chief architect of Yibao Pay’s product center, delivered a public session on how technology professionals can cultivate their "inner skills"—both technical fundamentals and personal growth.

Personal Background

Li has worked at Citibank, Oracle, Reuters, and Sina Weibo, handling education systems, foreign‑exchange trading platforms, and video services. At Yibao Pay he leads architecture planning, core system construction, payment channels, merchant platforms, technical standards, and financial security firewalls.

Distributed Service Architecture

The architecture aims at six goals: high availability, high performance, scalability, extensibility, security, and consistency. Availability is measured by "four nines" and improved through architecture and design reviews. Performance relies on a "divide‑and‑conquer" approach, which introduces consistency challenges. Security targets five objectives—leak prevention, tampering prevention, repudiation prevention, eavesdropping prevention, and man‑in‑the‑middle protection—addressed with encryption, signatures, and mutual TLS.

Scalability is achieved via horizontal expansion (e.g., sharding databases, caching, message‑queue smoothing). Extensibility refers to rapid functional iteration, distinct from scalability. Consistency remains a core difficulty in micro‑service environments.

Recommended reading includes "Billion‑Level Traffic Site Architecture Core Technology" (high‑concurrency front‑end), "Distributed Service Architecture Principles, Design, and Practice" (micro‑services, consistency, APM, containerization), and "Large‑Scale Website Core Technology" (foundational concepts).

How to Cultivate Technical Inner Skills

Key areas are operating‑system fundamentals (CPU, memory, disk I/O, network I/O), algorithms and data structures (including advanced topics like dynamic programming, greedy, pruning, recursion), high‑concurrency services (divide‑and‑conquer), and big‑data foundations (MapReduce, GFS, Bigtable).

Evaluating a Candidate’s Technical Ability

Three dimensions are considered: breadth (range of technologies, languages, tools), depth (expertise in specific topics such as GC principles or database indexing), and height (purpose and future relevance of the technology).

Goal‑Methodology Framework

The framework consists of goal, principle, method, and result. Correct goals must be measurable; principles define constraints; methods are weighed for cost‑benefit; results must align with the original goal.

Personal Principles for Work and Life

Reliability and intelligence: being trustworthy and adaptable.

Boldness and optimism: daring to try and staying positive.

Perseverance or decisive action: when facing obstacles, choose to endure, act decisively, or move on.

Effective communication: empathic thinking that considers both others’ and one’s own perspectives.

Q&A Highlights

Questions covered self‑learning for junior iOS developers, the value of gaining backend experience for client developers, and career comparisons between front‑end and back‑end paths. Li emphasized deep specialization, continuous practice, and the importance of building expertise in one’s chosen domain.

Author: Li Yanpeng, chief architect at Yibao Pay and author of "Distributed Service Architecture: Principles, Design, and Practice".