AliExpress has transitioned to a microservices architecture from a monolithic architecture. This involved several key changes:
1. Organizing code into individual services rather than global jars to improve independence and reusability.
2. Adopting Docker to standardize environments and dependencies.
3. Integrating Alibaba cloud services like configuration (Diamond) and messaging (MetaQ) into applications using Spring starters to simplify usage.
4. Establishing practices like publishing clean API-focused jars, using Maven to manage dependencies, and applying naming standards to improve maintainability at scale.