Swift at Apple: Migrating the Password Monitoring Service from Java

Swift at Apple: migrating the Password Monitoring service from Java June 2, 2025 Swift is heavily used in production for building cloud services at Apple, with incredible results. Last year, the Password Monitoring service was rewritten in Swift, handling multiple billions of requests per day from devices all over the world. In comparison with the previous Java service, the updated backend delivers a 40% increase in performance, along with improved scalability, security, and availability. The Passwords app, introduced in the fall of 2024, helps users manage their passwords, passkeys, and verification codes. It allows them to store, autofill, and generate strong passwords that can be shared across all their devices, as well as share passwords with trusted contacts. One security feature included in the app is Password Monitoring, which warns users if one of their saved passwords shows up in a data leak. This feature has a server component that is maintained by Apple. On a regular inte ... Read full article.