Wallet Engine: White-label digital wallet platform built from zero - multi-currency, crypto-native, and AML-compliant on day one.

The Challenge

Building a white-label wallet from zero is not a standard software project. It requires simultaneous decisions across architecture, payment infrastructure, compliance, and extensibility - all before a single line of product code is written. A wrong decision at the infrastructure layer at that stage is expensive to reverse and can constrain the platform for years. Wallet Engine needed a technology partner capable of making those foundational decisions correctly, not just executing against a specification. The compliance dimension was non-negotiable. A wallet platform that processes real payments, holds balances, and supports multiple currencies - including cryptocurrencies - operates inside a dense regulatory environment. AML obligations cannot be bolted on after the fact; they need to be embedded in the transaction architecture from the start. At the same time, the platform needed to be genuinely white-label: flexible enough for any business to operate under its own brand and rules, without requiring bespoke engineering for each customer.

The Approach

Gradion acted as lead technology partner from the initial business idea through MVP launch and into subsequent product iterations. The engagement covered everything from architecture decisions and infrastructure selection through to API design and feature development - functioning as the engineering arm of the business rather than a delivery contractor. The core infrastructure choice was Mambu, the cloud-native core banking platform that also underpins N26 and Revolut. This decision established a production-grade, regulation-aware financial infrastructure foundation from the outset, avoiding the years of engineering work required to build equivalent capabilities in-house. On top of Mambu, Gradion designed the payment solutions architecture and built the API layer that exposes wallet functionality to white-label customers. AML compliance was integrated directly into the payment flow rather than applied as a downstream check. Every transaction passes through real-time compliance logic - a design decision that protects Wallet Engine’s customers from regulatory exposure and makes the platform credible to enterprise buyers operating in regulated markets. As the product evolved, Gradion extended the platform into cryptocurrency support, including a proprietary coin and marketplace functionality. Each of these capabilities was built as a native extension of the existing architecture rather than a bolt-on - ensuring the platform’s structural integrity as its scope expanded.