Transparency Report: May 12 Crypto Data Incident

Wanted to be upfront about an issue we had today with StockJelli's crypto momentum alerts.

What happened: We pushed an update this morning to expand our crypto coverage from 250 to 350 coins. This pushed our CoinGecko API calls over their free-tier rate limit. CoinGecko started returning 429 errors, which meant our price cache stopped refreshing. For about 5 hours, our crypto screener was serving stale prices — and 5 alerts fired using those frozen prices.

What we did:

- Identified the root cause (rate limit from coverage expansion)

- Reverted the change immediately

- Added automatic 429 backoff protection so if this happens again, we cool off for 2 minutes instead of hammering the API and getting IP-banned for hours

- Removed all 5 affected crypto alerts from our notification log

What was NOT affected: All stock alerts (powered by FMP + Tiingo, separate infrastructure) were unaffected. Our v2 formula track record remains clean.

Lessons learned: We should have load-tested the API call budget before deploying. We're also planning to add a stale-data detector that flags when prices haven't changed across multiple polling cycles.

We'd rather delete alerts than inflate our stats with bad data. Transparency matters more than vanity metrics.