Explore modern immutable data structures in C++ through this conference talk from C++Now 2017. Dive into the architectural benefits of immutability and learn how to build efficient persistent vector types using Relaxed Radix Balanced Trees. Discover Immer, a C++ library for implementing efficient immutable data structures. Follow along as the speaker demonstrates a text editor application built using these principles, showcasing both simplicity and performance. Gain insights into value semantics, structural sharing, and concurrent programming without locks. Cover topics including the data model, balanced trees, algorithms, transience, and performance. Examine the Flax architecture and data-driven approach in building robust C++ applications.