How AWS Uses Formal Methods to Build Reliable Services

Amazon Web Services (AWS) employs a multi-pronged approach to building reliable services, leveraging formal methods from TLA+ to the newer P language, alongside lightweight techniques like property-based testing, fuzzing, and fault injection. These methods not only help AWS identify and eliminate subtle bugs early in development, boosting developer velocity and efficiency, but also provide a robust foundation for performance optimization. The article also explores challenges like metastability and future opportunities using LLMs and AI assistants to lower the barrier to entry for formal methods.