An export is a rebuildable representation of authoritative NDJSON partitions.
Oko export#
LAKE_DATA/exports/oko/runtime=<runtime>/<session-hash>.jsonl groups conversation events per session using the oko-import-v1 line schema. Deterministic event UUIDs make replays deduplicable; rows sort by timestamp then UUID. export-cursors.json tracks partition size, physical size, and mtime for incremental refresh.
Oko reads this projection. Oko does not own it, write the Lake, or replace masking. rebuild-oko reconstructs it; oko-refresh asks Oko to reindex the current export.
Parquet#
compact writes LAKE_DATA/parquet/runtime=<runtime>/events.parquet through DuckDB. It is an analytical mirror, not a transaction log.
clean --target parquet|oko|all previews derived removal. --apply removes only selected Parquet/Oko trees; it never removes canonical events, cursors, or labels.
Derived artifacts can be stale and may be deleted/rebuilt. Canonical partitions cannot.
See architecture and CLI reference.