# Your company needs to track customers across multiple source systems (CRM, website, mobile app)

Canonical URL: <https://datadriven.io/problems/your-company-needs-to-track-customers-across-multiple-source-0b348c44>

Domain: Data Modeling · Difficulty: medium

## Problem

Your company needs to track customers across multiple source systems (CRM, website, mobile app). Design a Data Vault hub to store the business key and enable tracking across sources.

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