Breez has partnered with Turnkey to let developers add non-custodial bitcoin to applications that run wallets from their own backend servers, the companies announced.
The partnership is aimed at what the companies described as a structural issue in mainstream app design. Many consumer apps run from the backend, with one service handling millions of users. In that setup, adding bitcoin has typically meant storing user keys on company servers.
That creates a custody problem. If a company holds the keys, it becomes a custodian, which can bring licensing requirements, legal liability, and the security burden of managing a large pool of user funds. The other option has been to build a separate device-based wallet, but that can break the architecture these apps use to scale.
A model built around user-controlled authorization
Under the new arrangement, each user receives a wallet whose keys are created and stored inside Turnkey’s secure enclaves. According to Breez and Turnkey, those keys remain out of reach of the application server, Breez, and Turnkey itself.
The backend keeps a credential that defines what actions it can take, while the authority to move funds remains with the user. In practical terms, the companies said, this gives some of the largest consumer apps a way to add non-custodial bitcoin without rebuilding their backend systems or taking custody of customer assets.
Turnkey supports Spark, the network on which the Breez SDK is built. Combined with Breez’s server mode, a single backend can manage wallets for millions of users without storing their keys.
How transaction approval works
The approval flow relies on a user-held credential, such as a passkey registered with Turnkey during signup. The server prepares the transaction and displays the amount, the fee, and the destination. The user then approves the transaction, and only after that does it complete. The server cannot spend funds without that approval.
For the user, the app’s existing flow stays the same, and there is no seed phrase to write down.
Positioned for exchanges, fintechs, and neobanks
Turnkey provides embedded wallet infrastructure used by a range of consumer apps and has a SOC 2 audit.
In a note to Bitcoin Magazine, Breez said the release gives exchanges, fintechs, and neobanks a way to offer bitcoin and stablecoin services to large user bases without taking custody of funds. Exchanges can automate payouts under rules defined by their security teams, while fintechs can add a non-custodial bitcoin service inside their existing interfaces.
Part of a broader Breez SDK push
The partnership extends a series of Breez SDK features designed to reduce barriers to bitcoin integration. Passkey Login replaced the seed phrase. Stable Balance was introduced to address price volatility. A separate feature added support for sending the stablecoins USDT and USDC.
The companies said those tools, taken together, allow backend-run products to offer bitcoin and stablecoins while keeping custody of the assets with users.
The article first appeared in Bitcoin Magazine and was written by Micah Zimmerman.