Residency slots live on machines; the run starts with exactly one; capacity grows primarily by acquiring machines with a researchable slots-per-machine ladder as a typed hook; swapping resident procedures is immediate. Persona binding and the rollback class of resident procedures stay [OPEN]. Defense: design-session capture per wiki/process/design-sessions.md phase 2, amending the owning spec's Learned-versus-resident section, criterion 10, and status note (wiki/mechanics/research.md). No runtime change; the research-graph work order remains DRAFT.