Apple App Store Frontend Source Code Leaked: Svelte, Internal Tools, and Production Practices Revealed

The full source code for the Apple App Store’s web frontend has been inadvertently exposed, reportedly due to misconfigured source maps left enabled in a production environment. This oversight granted access to unminified TypeScript files, complete with comments, dependency structures, and internal folder organization, providing a rare glimpse into Apple’s internal web development practices.

Key revelations from the leaked codebase include the surprising choice of Svelte as the primary UI framework, a departure from more common enterprise selections like React, Angular, or Vue. The repository also confirms the extensive use of TypeScript, SCSS for styling, and external libraries such as Sentry SDK for error monitoring and Floating UI for tooltips. More significantly, the leak uncovers several proprietary Apple systems and frameworks, including ‘Jet’ for core business logic, ‘AMP’ (distinct from Google AMP) for Apple Media Services components, ‘Perf Kit’ for performance monitoring, ‘Radar’ as an internal issue tracking system, and ‘Kong’ potentially serving as an internal firewall or origin check service. Codename references like Scandium, Mandrake, Charon, and Tinker Watch suggest additional internal projects. The code further provides insights into enterprise-level frontend architecture, a mix of server-side and client-side rendering for SEO. Observations on code quality range from well-documented sections and adherence to avoiding ‘Magic Strings’ to instances of hardcoded values, complex conditional logic, and specific Safari bug workarounds.