Greenlight by Blockstream allows developers to seamlessly integrate non-custodial Bitcoin Lightning payments into their apps.

Our goal was to build a non-custodial service that empowers developers to add Lightning functionality to their applications with minimal overhead, while ensuring users retain full control over their funds. Built on Core Lightning's modular architecture, Greenlight separates Lightning node operations, managed by Blockstream, from Lightning transaction signing, which remains in the hands of the user.

Challenge

Given the high standards of the Bitcoin ecosystem, Greenlight required a signing solution that was open-source, reliable, scalable, and developer-friendly. Prior to VLS, securely managing Lightning private keys in a hosted setting without taking custody of user funds was almost impossible.

Why we Chose VLS

We chose VLS because it enables secure signing of transactions, separate from node operations. This aligned perfectly with our non-custodial goals while handling complex Lightning transactions in a hosted environment. VLS’s cross-platform compatibility gave us confidence that developers could deploy Greenlight across web, mobile, or consumer devices. VLS enabled Greenlight to build a highly secure and scalable non-custodial Lightning infrastructure.

What we did

During implementation, we customized VLS to integrate smoothly through the API, making it adaptable to our needs and easy to work with for developers. While developers still need to handle aspects of key management, such as defining seed storage and backup, Greenlight and VLS provide tools to streamline this process. This makes it easier to deploy Lightning payments while maintaining Bitcoin’s core principles of user control.

Results

By hosting the node infrastructure while letting users retain custody of their signing keys, Greenlight offers a streamlined development experience and robust security, allowing teams to focus on building new features.

Since integrating VLS, Greenlight has significantly improved both security and the developer experience for those deploying non-custodial Lightning payments. Positive feedback from developers highlights the ease of integration and reduced complexity in key management, leading to fewer support queries. Users benefit from full control over their Bitcoin, and developers are provided with a solid foundation for building scalable, secure applications on the Lightning Network.