Hestia is our software architecture solution, which provides an visual diagram editor for design artifacts like system diagrams, design diagrams and process flows.
These are hierarchical, so clicking on the expansion link will navigate to the related sub-architecture, and back links return to the parent architecture. This allows for deep granularity as well as system-wide complete coverage.
Crucially, the architecture diagrams can automatically create or update your code base, if so desired. Test plans and associated user guides are also updated if impacting changes are made via Hestia.