Blogs›Stripe›CI Performance and Test Execution
This feature thread tracks Stripe's continuous efforts to optimize its Continuous Integration (CI) pipeline and testing infrastructure to handle a massive, rapidly growing codebase. Initial focus was on improving test execution speed and efficiency, leading to the development of sophisticated systems like Selective Test Execution. This system allows Stripe to run only a small percentage of tests on average, significantly reducing CI times and enabling faster development cycles. This post details how A/B testing can be integrated into the payment flow to optimize performance and reduce code complexity, further enhancing the CI/CD process by enabling data-driven decisions for feature rollout and iteration.
6/1/2026
This post introduces the use of Apache Spark to scale microservice testing, addressing the challenge of testing services with complex input dependencies. It highlights how Spark's parallelism and scalability can be used to build regression test harnesses, enabling comparison of old and new implementations, modeling of rule changes, and impact quantification.
4/9/2026
This post details the technical implementation of Stripe's Selective Test Execution system, explaining how it leverages code dependency analysis and test impact prediction to minimize the number of tests run for each code change in a 50M-line Ruby monorepo. It discusses the challenges of scaling CI for large codebases and the strategies employed to achieve fast CI by running only a small percentage of tests on average.
10/23/2024
This post details how Stripe's A/B testing capabilities can be leveraged to optimize payment flows and reduce code complexity. It explains how A/B testing allows for data-driven decisions in feature rollout and iteration, contributing to faster development cycles and improved CI/CD efficiency.
5/4/2022
This post details the engineering challenges and solutions for ensuring both fast and secure builds within Stripe's CI system. It discusses the trade-offs between build speed and security, and the strategies employed to achieve both, including the use of open-source technology and novel engineering approaches to meet high security standards.