Snowflake

PUT/COPY from an internal stage or an external stage on S3/GCS/Azure. Native `MERGE`. Replace is `CREATE OR REPLACE`.

Every destination receives the same layout; see the tables Ingest creates.

Staging

needs_staging: any. Staging always happens in the destination's own cloud and region; data does not take a detour through ours.

Conformance

Every adapter passes the same suite before it ships: create a table with every canonical type, append 100k rows, atomic replace, merge (latest dedup_sort wins; child tables delete-then-insert by root id), schema evolution, NULL-key rejection, package replay without duplicates, state and schema round-trip, row-count read-back, identifier edge cases, double-underscored table names (__quarantine, child tables), and rollback on a mid-load failure.