Mental model (DS, aliases, DAOs)

The three things

• Dataset Snapshot (DS): immutable dataset identity (fingerprint of canonical bytes).
• Alias: a local name (e.g., "brca") that points to a DS and has append-only history.
• DAO (DatasetRef): the notebook object that resolves aliases, shows history, loads DataFrames, and moves pointers safely.

The only rule that matters

DS identity is data-only. Notes, alias names, and user intent do not change fingerprints.

“use” vs “v()”

• use(...) updates the alias pointer and logs an alias event.
• v(k) returns an immutable handle to version k without touching pointers.