Let's Explore Lightning

[DanGould]

• To lessen the burden of "toxic" change
• To lessen the effect of fees

Lightning Labs recommended a zap-like implementation with lnurl connection to a full node. Then, they suggested we iterate to a full lnd process hooked up to neutrino or our own block filters.

@johnsBeharry pointed me towards @MaxHillebrand 's tweet on spending change with the @BoltzExchange service.

Instead of sitting on that change output what if it went right to Boltz or opened a channel otherwise?

I'm sure it would be a can of worms to implement anything beyond an API call so we must discuss the tradeoffs.

[nopara73]

• WIP: Security and Privacy of the Lightning network lnbook/lnbook#524
• https://mobile.twitter.com/GeorgeKappos/status/1352969635679920131
• https://arxiv.org/abs/2003.12470

[DanGould]

peakshift/bitcoin-ux#20 (comment) outlines this exact issue in this medium post with Boltz

[DanGould]

Though not exactly change, lightning channels for newbs can benefit from turbo channels to receive right away

It's a 0-conf channel

[DanGould]

if using default off-chain mechanism

non-interactive channel

• receive payment which automatically funds a payment between user & service provider
  splice out
• close channels, make on chain payment, open new channel with change
• lets you keep funds in lightning & pay on chain
  submaine swaps

[DanGould]

Routing payments can be outsourced to a service provider without giving up privacy by using trampoline payments

[vindard]

Adding some notes from a call yesterday to this thread

Notes

What is Chaincase?

• Private way to sync
• Chaumian coinjoin
• Network level privacy

Note: Chaincase prioritizes sovereignity, and privacy + non-custodial are how it achieves this

Open questions Dan wants to explore:

• How can lightning be used, if many users may be coming in from things like Strike and other lightning wallets?

• What is Chaincase's USP (Unique Selling Proposition) for integrating Lightning? ... or what's the clear use-cases for integrating Lightning that can both complement and enhance the existing Chaincase product offering?

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Current infrastructure

Chaincase infrastructure details (some random notes, Dan can expand/clarify):

• wasabi implementation of neutrino
• how does it relate to channel opens?
• we operate a backend service for requesting the blockfilters

Chaumian coinjoin

• Own Wasabi coordinator

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Implementing Lightning non-custodially

Services/implementations to explore:

• LNDHub (BlueWallet)
• LSP, Lightning Service Providers (Breez wallet)
• lnurl
• LDK, Lightning Dev Kit
• Muun wallet (blogpost; podcast)

> Where does the distinction fall between the custom/non-custodial parts of the above options?

> What does lnd need to do on the client, and what can a service provider do?