The model

Virta has one store: an append-only log of events. A task is never stored; it is a view folded from the events that mention it. Comments, tag changes, body edits, attachments, closes and reopens are all events, so the card's transcript is the log rendered — there is no second structure to keep in sync.

Every event is attributed by the identity of the credential that wrote it (by). Locally that is whatever identity the store was opened with; against service-compris it will be the scoped capability token.

Tags are the whole model: bare keys (bug) or key:value (status:doing, project:tosijs-ui). Workflow is a tag convention the tool never enforces.