The evolution of Facebook’s iOS app architecture

This post details the evolution of the Facebook iOS app architecture over 10 years, highlighting key technical decisions and their impact. It covers the shift from Core Data and MVC to a custom declarative UI framework (ComponentKit) for improved performance and maintainability, and the strategic adoption of dynamically loaded libraries (dylibs) to manage app size and startup performance. The post also discusses the challenges and solutions related to dylib integration, including runtime failures and linker errors, and the subsequent reliance on the Buck build system for code generation and dependency management.