Seven crypto exchanges, one normalized schema...

This is a follow-up to my previous post on building a funding-rate arbitrage scanner. That post was about the product — what it does, the three non-obvious gotchas, and why I built it. This one is about the plumbing: how seven different exchange APIs handle the same data and what it took to unify them. If you've ever thought "I'll just call the public APIs and join the data, how hard can it be" — this post is for you. The dataset I wanted For each USDT-margined perpetual on each major venue, I n