Time machine → As-of
Inspect a dataset-level observation from a captured date.
Pick one of the sources named below and a date. Fonteum will select the stored dataset-level observation whose selection window contains that date and show its row count and attested hash plus any witness and chain metadata. These observations do not replay an individual record and do not prove that the upstream source changed on the observation date.
How the as-of read works
- The picker is limited to the named entries in this tool. A scheduled observation records dataset-level metadata such as a row count; it is not a banked copy of every source row.
- Your as-of date selects the stored observation whose selection window
[attested observation, next attested observation)contains your date. The window is a lookup rule, not evidence that the upstream dataset stayed unchanged. - Only observations with a complete attestation row enter public coverage. The page exposes the stored hash plus any witness and chain metadata; an integrity-read error makes the lookup unavailable instead of returning partial evidence.
Dataset-level attestation metadata does not sign individual fact rows, and it does not establish what an individual record showed. Row-history replay is available only on named source-specific surfaces that actually retain superseded rows.