After each completed UTC month, a GitHub Release tagged
bitstamp-btcusd-1m-YYYY-MM holds a full-history join through that month-end.
The daily workflow (update-automation.yml) runs scripts/publish_monthly.py --if-due --publish after a successful append/validate. On the 1st UTC day, if the updates file already contains the last minute of the previous month, it publishes. On other days it skips. If that tag already exists, the daily job skips instead of failing.
Retry or dry-run from Actions: Monthly snapshot release (workflow_dispatch) with year_month (for example 2026-08). Leave publish unchecked to write artifacts/monthly-snapshot/ only.
uv run python scripts/publish_monthly.py --year-month 2026-08 --output-dir artifacts/monthly-snapshot
Assets: btcusd_bitstamp_1min.csv.gz, btcusd_bitstamp_1min.parquet (integer timestamp, float64 OHLC/volume), btcusd_bitstamp_1min_provenance.csv (sidecar clipped to the snapshot), manifest.json. Snapshot identity is the SHA-256 of the canonical manifest file.
The first tag bitstamp-btcusd-1m-2026-08 prepends scripts/first_release_intro.md. Later months do not.
Do not overwrite an existing tag. Do not rewrite daily data/ files. Root README documentation is human-owned.