observability

We benchmarked all 67 prod-code AST tools against prometheus/prometheus: 385K lines of Go, 84 packages, 1,485 error checks, 99% slicing reduction, and Bug #740 fixed in remote module dependencies.

A 32-core node sitting at 2% load, a one-millisecond network, and half the queries taking 40 ms. Three things we found while measuring instead of guessing, including one optimisation that did not work and one that deadlocked.

22 exchanges (Binance, OKX, Bybit, Coinbase and more), 240,000 records per second, zero crashes all summer, and a dozen incidents where data vanished silently. Where to put the collector, what breaks without an error in the log, and which metrics give it away.