Product Requirements are never one-time documents. They live and evolve for many years. Documents are often entangled, depending on each other. There must be a way to answer a question "What has changed?" for any two versions of a graph. Reflecting these properties requires a more sophisticated structure than "folder-document."
We found a solution by adopting Git ideas but crafting them to support a nested structure of rich documents and work in a browser without a need for a file system. Let us introduce you to the result!