doorstop

Doorstop is a requirements management tool that facilitates the storage of
textual requirements alongside source code in version control.

When a project leverages this tool, each linkable item (requirement,
test case, etc.) is stored as a YAML file in a designated directory.
The items in each directory form a document. The relationship between
documents forms a tree hierarchy. Doorstop provides mechanisms for modifying
this tree, validating item traceability, and publishing documents in several
formats.