mvcc-append-only-versions

Status: IN

Writers never modify existing `Version` objects (except self-overwrites); new values are appended to per-key version lists, preserving the immutable snapshot for concurrent readers

Source: entries/2026/05/29/topic-mvcc-snapshot-isolation.md

Example

self._versions.setdefault(key, []).append(
    Version(key, value, created_by=tx.tx_id))

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