Eleven thousand violations, one wrong input
Deribit's mark surface breaks static arbitrage 11,593 times across 88 snapshots. Its own quotes, scanned the same way, break it never. Most of the gap turns out to be a single stale number.
Writing
Long-form
One piece per finding, with the argument set out properly rather than compressed into a card. Each states what it does not show.
Households diverge in a shock, not in general
Rebuilding US CPI from its eight components recovers the published headline to 0.083 percentage points. Reweighting it for different households shows they live at much the same rate for years, then come apart exactly when the number is quoted hardest.
The curve is measured, the split is a choice
Rebuilding the New York Fed's term premium model reproduces the fitted yield curve to 0.45 basis points. The premium extracted from that same curve reproduces to 14, and moving the start date alone moves it 81.
Measure the book before you allocate for it
The obvious structure for a price-indexed order book is one flat array. A real Coinbase snapshot says that array would be a hundred gigabytes of almost entirely zero, and the same snapshot says exactly what to build instead.