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I Built a BFIU-Compliant AML Detection System in Python (Here's Why the Kaggle Approach Doesn't Work

I Built a BFIU-Compliant AML Detection System in Python (Here's Why the Kaggle Approach Doesn't Work)

Most AML tutorials end with a confusion matrix and a 99% accuracy score. Here's why that doesn't work — and what I built instead. I've been working in fintech compliance data for a while. The one thing I kept noticing: every "fraud detection project" on GitHub or Kaggle uses the same dataset — the UCI credit card fraud dataset from 2013. It has 284,000 rows, 30 features labeled V1-V28, and approximately zero explanatory value for anyone who wants to understand how financial crime actually works. So I built something different. The problem with the standard approach Real transaction monitoring engines don't work like Kaggle competitions. They don't take a CSV, train a model, and output a probability score. They work like this: A rule engine runs first — deterministic, auditable, regulatory-cited rules that generate alerts Those alerts get scored and triaged by risk tier An ML layer reduces false positives among the high-risk alerts ...

How I Caught a Massive Layering Scheme in Mobile Banking

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Photo by Roger Starnes Sr on Unsplash I still remember the day our team detected a massive layering scheme in our mobile banking system. It was a typical Monday morning when our alert system started buzzing with unusual transaction patterns. The numbers were staggering - over 10,000 transactions in a single day, all below the BDT 100,000 threshold, and all of them were layered in a way that seemed almost impossible to detect. The Hidden Problem As I dug deeper, I realized that our AML rule engine was missing a critical aspect of layering detection. The engine was designed to catch obvious structuring attempts, but it was not sophisticated enough to identify complex layering schemes. This was a major concern, as layering is a common technique used by money launderers to evade detection. According to the BFIU guidelines, layering is defined as the process of moving funds through multiple transactions to disguise the origin of the money. In mobile banking, layering can be particularly ch...