Domain‑Driven Design and Microservice Architecture Evolution at Qunar.com

The session begins with introductions of the speakers, Li Quandang and Zhu Haoman, who have extensive experience in system development and architecture at Qunar.com.

It outlines the architectural evolution path: starting from a monolith, moving to service‑oriented architecture, then to platformization, and finally to a mid‑platform (domain‑driven) approach, highlighting how each stage addresses business growth and complexity.

The design philosophy stresses business‑driven microservice evolution, focusing on commercial maturity, business change frequency, and technical decision latency, while applying Conway's Law and its inverse to align system design with organizational structure.

Four reconstruction patterns are presented—Repairer, Executioner, Evolutionary, and Hybrid—explaining their trade‑offs and selection criteria for Qunar's hotel information system.

A detailed DDD process is described, covering vision setting, domain expert identification, event storming, bounded context definition, sub‑domain classification, domain modeling, and mapping to code, with emphasis on unified language and modularity.

The COLA framework is introduced as the implementation backbone, providing a layered architecture (adapter, client, application, domain, infrastructure, common) and supporting CQRS for command‑query separation.

Outcomes include reduced microservice count, improved development and QA efficiency, clearer domain boundaries, and enhanced organizational alignment, followed by a Q&A addressing DDD reconstruction challenges and COLA adoption.