Late Trade Settlements

Concepts covered: paReconciliation, paStreamingPlusBatch, paLateData

A capital-markets data platform delivers per-symbol minute bars to algorithmic trading desks. The bars must be available within seconds of the minute closing. They must also be reconcilable to the firm's official settlement system within audit tolerance. Trade fills sometimes settle late: cross-border trades that book through a foreign settlement window can land back-dated by a full business day. The design composes a streaming pipeline, a schema policy, and a reconciliation pass to satisfy both consumer needs. The Architecture The streaming pipeline serves the algorithmic desks during market hours. The reconciliation pass overwrites yesterday's bars overnight, after the settlement system has finalized. The minute_bars table has two writers; the contract is that the daily reconciliation is

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