Skipper：构建 Airbnb 的嵌入式工作流引擎

How Airbnb built a lightweight workflow engine to solve durable execution.

Airbnb 如何构建轻量级工作流引擎来解决持久执行问题。

View from the deck of a sailing boat gliding across sun-dappled water, with ropes, mast, and boom in the foreground and a distant shoreline under a clear blue sky.

从帆船甲板上眺望，帆船在阳光斑驳的水面上滑行，前景中有绳索、桅杆和横桁，远处海岸线在晴朗的蓝天下。

By: Ricardo Gamba, Andriy Sergiyenko

作者：Ricardo Gamba、Andriy Sergiyenko

Introduction: The durable execution problem

引言：持久执行问题

Picture this hypothetical flow: A host submits an insurance claim about their listing to Airbnb. The system needs to validate the claim, run trust and safety checks, assess estimates, process the payout, and send notifications. Halfway through — after the validation passes, but before the payout — the server crashes.

想象这个假设流程：一位房东向 Airbnb 提交关于其房源的保险索赔。系统需要验证索赔、运行信任和安全检查、评估估算、处理支付并发送通知。过程中途——验证通过后，但在支付前——服务器崩溃。

What happens next?

接下来会发生什么？

In a traditional architecture, the answer is often “it depends.” Maybe the operation times out and the guest retries, triggering duplicate processing. Maybe partial state corrupts what comes next. And for workflows spanning minutes, hours, or even days, such as our insurance claim example, interruptions are all too likely.

在传统架构中，答案往往是“it depends。”。也许操作超时，客人重试，触发重复处理。也许部分状态损坏后续内容。对于跨越分钟、小时甚至天的工作流，如我们的保险索赔示例，中断是非常可能的。

The industry has developed solutions for this, such as dedicated orchestration clusters and cloud-managed workflow services. However, these solutions come with their own costs: operational complexity, infrastructure dependencies, and architectural constraints.

行业已经开发出解决方案，例如专用的编排集群和云管理的 workflow 服务。然而，这些解决方案带来了自身的成本：运营复杂性、基础设施依赖和架构约束。

We needed durable execution without the overhead. This article describes how we built Skipper, an embedded workflow engine now powering critical workflows across insurance, payments, media processing, and infrastructure automation at Airbnb.

我们需要无额外开销的持久执行。本文描述了我们如何构建 Skipper，这是一个嵌入式工作流引擎，现在在 Airbnb 的保险、支付、媒体处理和基础设施自动化等关键工作流中发挥作用。

Why existing solutions fall short

为什么现有解决方案不足

Before building Skipper, we e...