Layout processing techniques have been described that allow processing of structured documents to be conducted, and for associated layout to be accomplished in a sequential manner. The layout process is split into multiple, smaller steps that can be executed sequentially. In at least some embodiments, a layout builder is utilized in conjunction with a stack to control layout execution on respective levels of the structural hierarchy of a structured document. Immutable data structures are utilized and allow for parallel execution of sequential layout operations. In at least some embodiments, partial execution of the layout sequence can be performed to produce usable data.