The last 10 years have seen a boom of functional-programming adoption for sizeable industrial projects. This is despite the fact that precious little has been written about the architecture of large functional programs. Many architectural styles and techniques common in the Enterprise world can’t be applied directly when using functional programming, or require significant changes. On the other hand, the benefits on architecture from using functional programming are significant: Design methodologies like Domain-Driven Design can be adapted to using functional programming, and then extended using combinator models and denotational design. The tutorial gives an overview of design and architecture techniques available to the functional software architect.