Forgettable Memory

Could have been 2.0. We didn’t.

Tombstones re-open the merge oracle. That is not a patch — it’s a lattice change. Plenty of systems would stamp 2.0 on “we finally have delete.” We chose 1.5 on purpose.

Why? Because the story was always one arc, not a reboot:

• 1.1 Mergeable — join without a coordinator
• 1.2 Sendable — seal · send · merge
• 1.3 Provable — stranger receipt, one command
• 1.4 Verifiable — which key sealed it
• 1.5 Forgettable — delete is state

2.0 would imply “throw out what you learned.” 1.5 says: same frozen discipline, one deliberate re-open, dual-implementation green, hand-golden gate — then ship. Semver is not a marketing amp; it’s a contract with strangers who already trust 1.x.

And yes: if we only shipped packet-path forget and left hosted resurrection as a footgun, that would have been a half 1.5. So 1.5.1 is the production cut — hosted pull / sync go through the same merge_souls CvRDT. There is no production 1.5.0. First 1.5.x on PyPI is 1.5.1.

Tombstones are rare code

Most “agent memory” products only ever append. Delete is UI theater — the backend still merges whatever last wrote. Distributed systems people know better: without a delete as state, absence is not information. Peers that lag will keep bringing the corpse back.

A tombstone is not a secure erase. It is a lattice marker — a little gravestone that travels with the soul and says: “this fact lost; do not resurrect on join.” That is the difference between hope and convergence.

What we actually ship:

• Soul.forget(id) / forget_text — remove the live fact and write a tombstone. Forgetting an id you no longer hold still suppresses it on later merge.
• CLI — forget <id> and forget --text "…" (id-less, matched by normalized text).
• LWW-tombstone-map above field-merge — delete-wins on ties; tags join under Rule T so the association gap doesn’t resurrect.
• GC out forever as debt — we don’t pretend compaction is free; the graveyard is honest debt until a later edition designs it.

This is the same rigor that froze the merge oracle in 1.1 — not vibes, not a feature flag named soft_delete. Dual-impl differential still green after the reopen.

What's New (1.5.0 lattice + 1.5.1 hosted)

• Forgettable Memory (packet) — tombstones on seal / merge / merge_souls. The deliberate oracle re-open, held to the same gate as the join itself.
• Hosted forget converges — namepoint pull / sync no longer re-add facts additively. They reconcile via merge_souls so a local tombstone suppresses a peer that still holds the fact.
• Namepoint.soul() — structured hosted read returns the full soul (facts and tombstones). facts() for recall stays facts-only.
• No wire change for push — tombstones were already storable; the read / reconcile side was the bug. Id-less tombstones round-trip by txt_hash.

Both transports — or it didn’t count

Portable memory has two roads: the packet (file, air-gap, chat) and the hosted namepoint (push / pull / sync). Convergent forget on only one road is a demo. On both, it’s a product.

If you still see a forgotten fact after pull, file a bug — that was the 1.5.0→1.5.1 gap, and it is closed on production PyPI.

Honesty bounds

• Tombstone ≠ secure erase. Disk, backups, and logs can still hold bytes. We claim lattice convergence, not forensic destruction.
• Delete-wins on ties under Rule T — intentional; document it if your app wants “last writer wins including resurrection.”
• No automatic GC of the graveyard in 1.5 — debt is visible, not magical.
• 1.4 provenance unchanged — optional Ed25519 stays opt-in; base path still zero-crypto.
• Grow/update-only is retired for delete — that bound from 1.1–1.4 is lifted here, on purpose, with evidence.

Try It

Release: v1.5.1 · PyPI: claude-fafm-sdk 1.5.1

The Numbers

• v1.5.1 — production on PyPI (Forgettable Memory · both transports)
• 232 tests green · 2 skipped · dual-impl still green after oracle reopen
• No 1.5.0 on prod — packet + hosted ship as one cut
• PyPI: claude-fafm-sdk 1.5.1
• GitHub: v1.5.1 release

The arc — through Forgettable

Mergeable → Sendable → Provable → Verifiable → Forgettable.

• 1.1 Mergeable Memory — souls join (CvRDT)
• 1.2 Sendable Memory — SPK1 + CRC travel
• 1.3 Provable Receipt — one-command stranger proof
• 1.4 Verifiable Provenance — which key sealed it
• 1.5 Forgettable Memory — tombstones · both transports · full stop on the volume

Memory that grows, moves, proves, signs — and can finally let go without lying about the join. Championship engineering, volume car energy: you drive it every day; the track car still exists when you want F1.

Nelly never forgets… unless you ask her to. And then the whole fleet agrees.

Next: Compactable (2.0) — epoch compact pays tombstone debt; cross-epoch merge refuses — no silent zombies.

Dual edge: Memory is vast — .fafm maps it. One format. Two edges. One soul. · PM.IR. — Permanent Memory. Instant Recall.