For payment platform engineers
Watch every leg of a cross-rail payment in flight. Find the regressed hop, read why — in plain text — without grafana, splunk, and a status-page hunt. Loop is what your on-call wishes the bank's API gave them.
step 01 · open
Drop a payment ID, an idempotency key, or a five-second time window. Loop pulls the legs from your rails and renders them inline — no Grafana hop, no link to Splunk, no separate logs window. The payment is the unit of work.
step 02 · find
Loop ranks legs by p99 deviation against your rail's seven-day baseline. The first one in the list is almost always the problem. The baseline is precomputed every five minutes per rail; you don't set it.
step 03 · read
Each leg carries an auto-generated explainer: which dependency regressed, which version of which service, which deploy correlates, and the diff between then and now. Plain text, copy-paste ready into a post-mortem.