Explore a 37-minute conference talk from ACM SIGPLAN's FUNARCH'23 that delves into building software architectures through the composition of state machines, drawing inspiration from Domain-Driven Design principles. Learn about the Crem library, a Haskell-based implementation that offers compositional and representable state machines. Discover how to create modular systems by combining independent subcomponents and keep implementations synchronized with graphical representations. Gain insights into using Haskell's advanced type-level features for specifying allowed and forbidden state transitions, as well as encoding complex domain-specific properties. Understand how Crem automatically generates graphical representations of systems from their domain implementations, enhancing the overall software design process.