Ticket

A handoff artifact scoping one session of work. Stands alone, or hangs off a spec as one of its children. Tickets can block or be blocked by sibling tickets, so the order of work falls out of their dependency graph rather than a linear plan.

Usage:

"Where do I start on the migration spec?"

"Look at the ticket graph — the schema change blocks the backfill, the backfill blocks the API switch. Pick a leaf and run a session on it."