How AliExpress Scales Global Teams with Microservices, Kotlin, and FaaS

AliExpress's technical team shares how they handle rapid releases and internationalization challenges.

Background

About five years ago, when DevOps was just emerging, a company claimed they could release dozens to hundreds of times per day, far outpacing traditional weeks‑long cycles. Today, AliExpress’s few‑hundred‑person tech team routinely releases dozens of times daily, thanks to three key factors:

Deep micro‑service decomposition with fine‑grained modules and a strict policy against heavy third‑party libraries.

Group‑wide operational standardization, especially comprehensive Docker adoption.

Continuous effort by the AliExpress SRE team to ensure stability.

Communication Bandwidth Attenuation

As the team became a truly distributed, international group (Hangzhou, Shenzhen, Moscow, Madrid, etc.) with 15% foreign engineers, communication bandwidth suffers:

Language conversion (Chinese to English) reduces efficiency.

From single‑site to multi‑site collaboration adds friction.

Time‑zone differences (e.g., 5‑hour gap between Hangzhou and Moscow) limit real‑time contact.

Cultural differences affect team‑building activities.

Rather than consolidating all engineers in one location, the team improves bandwidth utilization through several measures:

Aligning with mainstream industry technologies (e.g., using open‑source Spring Boot for Alibaba ecosystem integration, discarding proprietary frameworks).

"English First" policy: documentation, comments, and tools are primarily in English, with Chinese optional.

Service discovery that makes every micro‑service visible, self‑describing, and searchable.

Embracing Kotlin

All Java developers are encouraged to explore Kotlin because of its conciseness and seamless Java inter‑operation, making it production‑ready.

Converting a Java module to Kotlin reduced code lines by one‑third without sacrificing readability. The team has adopted Kotlin for new services, and the Russian office already runs production workloads in Kotlin.

FaaS

Function as a Service (FaaS) is more than a buzzword; it offers cost‑effective, on‑demand scaling compared to traditional Docker‑instance pricing.

Because functions are stateless and lightweight, millisecond‑level auto‑scaling is feasible, especially with technologies like GraalVM.

What Is Lightweight?

Many engineers forget the concept of lightweight services; a simple JAR often contains less than 10% business code, with the rest being heavy client or shared libraries that increase memory usage and startup time.

Well‑designed micro‑services should expose lightweight interfaces that can be invoked via HSF generic calls without pulling in heavy dependencies.

AliExpress has prototyped a Kotlin DSL combined with HSF generic calls to create functions that require only a minimal FaaS SDK, allowing business owners to focus solely on logic without worrying about library upgrades or capacity planning.

Do not discuss your programming history with developers; outdated experiences add unnecessary friction.

In summary, the team continuously pushes AliExpress to adopt Kotlin, micro‑service best practices, and FaaS to improve development efficiency and operational scalability.

Write‑in‑the‑final: Interested engineers are welcome to join the international team via email at [email protected].