This article was originally published on JustSoftLab Insights .

We've shipped RAG systems for regulated fintech clients across the past two years — fraud detection augmentation, compliance documentation Q&A, regulatory filing analysis, internal policy assistants. Across those engagements one pattern keeps repeating: the same ten architecture mistakes show up in roughly 9 out of 10 first production deployments, and they show up in a predictable order.

This isn't a list of bad models or weak engineers. The teams that ship these systems are usually capable. The mistakes are systemic — patterns the public RAG tutorials ignore because the demo data doesn't expose them, and patterns the vendor marketing actively obscures because admitting them would soften the sell.

If you are about to greenlight a RAG build inside a fintech, this is what we'd flag before you sign the SOW.

Why fintech RAG fails differently from generic RAG

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