FA-85624 / Ride-hailing fare and surge pricing / Member archive

Request stamped before its quote treated as locked · case 04

Replayed or skewed requests reuse quotes that were not yet issued.

Member previewVariant 4 · 3 implementations · 7 checks per implementation

Case contract

A fare quote locks its surge for 300 seconds: requests with 0 <= elapsed < 300 seconds are locked (a request timestamped before the quote, from clock skew, is not). A locked request uses the lower of the quoted and current surge; otherwise the current surge. Price = core x surge / 10, half up. Return [price, locked|requoted].

Why this case matters

Ride-hailing prices are computed per trip at scale; ordering, unit and boundary slips become systematic over- or under-charging.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression: clock skew	`[1998, "locked"]`	`[2498, "requoted"]`	Failed

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