[enmand]

What

Documents a parity caveat discovered while implementing #221's parent verification: a parent-bearing child whose parent has been deleted is a permanent dead letter, and replicas holding the same valid messages can converge to different Record state. Role revocation has the same shape.

Why it matters

• Current Enbox (and Rust after #221 PR A) resolves a parent by its current, not-deleted state. A delete is terminal.
• A child delivered after the parent's delete is rejected as a missing parent; repair can never succeed.
• An earlier-delivered child is admitted and a later soft delete does not cascade to it.
• This conflicts with DWN-REC-004 read as a global admission guarantee.

Contents

Adds a "Known parity caveat" section to implementation/dependency-resolution.md covering:

• the arrival-order consequence and the DWN-REC-004 conflict (parents and role revocation);
• why the timestamp-relative alternative is rejected (messageTimestamp is author-controlled, so an author could backdate a child past the parent's delete; late tombstones also prevent convergence on their own);
• the chosen interim behaviour: the client-facing reply stays generic, and the receiver classifies a tombstoned parent as terminal (Invalid) locally, which does not restore convergence but avoids a tombstone-existence oracle;
• an explicit Open decision block for the convergence mechanism.

Notes

This is documentation only. It does not change normative DWN semantics; it records current Enbox parity, the Rust interim classification, and the unresolved decision.

Update: ADR 0007 added

This PR now also records the decision as decisions/0007-retained-parent-ancestry.md and updates decisions/README.md, implementation/dependency-resolution.md, and DWN-REC-004 accordingly.

• Structural parent existence is evaluated against the parent's retained initial write, not its current liveness.
• A soft delete does not remove ancestry (and does not seal or hide children); prune removes ancestry and is terminal.
• Tracks adoption: Retained parent ancestry: a soft delete does not remove ancestry; prune does (ADR 0007) enbox#1684 (TypeScript), Retained parent ancestry: a soft delete does not remove ancestry; prune does (ADR 0007) enbox-rust-core#304 (Rust), Track ADR 0007 (retained parent ancestry) adoption across implementations and spec #19 (knowledge).