Also, I know you met with the Spark people and somehow they talked you into this, but please be assured that Spark is NOT self-custodial. They're just running Lightning Nodes for you. This is very likely why their server-side code is not public. It would make it PAINFULLY clear that they are custodying your users' funds... All of this will be fine until a Democrat wins in the U.S., and at that point they'll need to KYC everyone, or probably will just shut down and give up.