Tandem Bank is building a customer-obsessed digital banking business in a regulated industry. Rather than focusing first on licensing and regulations, Tandem prioritized customers by starting with their needs and feedback. Tandem developed a banking platform and app that aggregates customers' financial accounts to analyze transactions and offer personalized solutions like better savings rates or credit cards. Tandem uses AWS services like Lambda, Kinesis, and RDS to power machine learning models that provide savings recommendations to customers in a personalized, scalable way. Lessons learned include starting with customers, testing ideas quickly, and favoring customer outcomes over technology.