Breez has partnered with Turnkey to let developers add non-custodial bitcoin to applications that run wallets from their own servers, the companies announced.

The partnership addresses a structural problem. Many mainstream apps operate from the backend, with a single service handling millions of users. Adding bitcoin under that design has meant holding user keys on company servers. 

Holding keys makes a company a custodian, a status that carries licensing requirements, legal liability, and the security burden of a large store of user funds. The alternative has been to build a separate device-based wallet, a change that breaks the architecture these apps use to reach scale.