The system described above isn't a fantasy, LSATs are used today by Lightning Labs to serve as an authentication+payment solution for Lightning Loop, a non-custodial on/off ramp for the Lightning Network. Lightning Labs, has also open sourced
aperture, a reference LSAT aware reverse-proxy used in production for all our systems. In the remainder of this section, we'll explore the motivation, lineage, and workflow of LSATs at a high level. For a more detailed speciation, please see the later sections of this specification.