Data Contract Observatory v1.0.0

Stable software and evaluation release with an append-only evidence model. The final v1 snapshot records two genuine same-day prospective runs, 7,010 current-vintage retrospective replay checks, 9/9 synthetic fault detections, and 0/1 clean-control false alerts. Same-day runs do not establish longitudinal revision-detection evidence; replay and synthetic validation are not prospective evidence. The automation, first-run bootstrap, and public evidence boundary are verified. See docs/v1-release-audit.md.

Data Contract Observatory v0.1.0

Data Contract Observatory v0.1.0

Initial public research and engineering foundation for an inspectable public-data contract.

Evidence

• pins the official ECB daily USD/EUR reference-rate series EXR.D.USD.EUR.SP00.A;
• freezes protocol 1.0.0 before the complete historical evaluation;
• records a first 385-observation run that passed every hard contract check and emitted no statistical review signal;
• separates contract failure, statistical review, and substantive source error throughout.

Experience

• ships an interactive failure laboratory for schema, identity, freshness, and extreme-return mutations;
• publishes the machine-readable latest run and direct routes to protocol, source, licence, and citation metadata;
• supports responsive layouts, keyboard interaction, visible focus, and reduced motion.

Engineering

• tests Python 3.10–3.13 with nine deterministic contract, calendar, transport, and mutation tests;
• schedules auditable ECB observations and deploys the latest recorded state to GitHub Pages;
• pins GitHub Actions to immutable, current Node 24-compatible releases.

Boundary

A contract failure establishes only that a response violated this repository's declared consumer contract at a recorded time. A statistical review signal does not establish that the ECB or an exchange-rate observation is wrong.