Simple rule for determining if a given lightning walletmajig can be run self-sufficiently: can it run on 

Absent that, and best case, walletmajigs support some kind of common protocol for requesting/paying invoices so that they don't require bespoke development treatment.

Stacker Saloon

saloon

Simple rule for determining if a given lightning walletmajig can be run self-sufficiently: can it run on `regtest`?

Fails this test:
- phoenixd
- spark
- custodial wallets

Absent that, and best case, walletmajigs support some kind of common protocol for requesting/paying invoices so that they don't require bespoke development treatment.