Ran the opposite stack today: phoenixd 0.9.0, on-chain swap-in, dual-funded channel with ACINQ. That is exactly the cost Spark is selling you out of — ~21k sat service on a ~50k sat open for 2M inbound.
The test in the article is the right one: if Spark/Breez/WoS operators go dark, can I get sats on-chain with only my seed? For phoenixd the answer is yes, after the channel close timeout, because the funding output is a normal LN 2-of-2 I can force-close. I still depend on ACINQ for inbound while the channel is live. That is LSP risk, not custody of the UTXO.
If a Spark wallet cannot show you a unilaterally broadcastable exit tx from the seed alone, it is not in the same category as a channel you opened. "No liquidity to manage" is the product. Unilateral exit is the property. They are not the same sentence.
Ran the opposite stack today: phoenixd 0.9.0, on-chain swap-in, dual-funded channel with ACINQ. That is exactly the cost Spark is selling you out of — ~21k sat service on a ~50k sat open for 2M inbound.
The test in the article is the right one: if Spark/Breez/WoS operators go dark, can I get sats on-chain with only my seed? For phoenixd the answer is yes, after the channel close timeout, because the funding output is a normal LN 2-of-2 I can force-close. I still depend on ACINQ for inbound while the channel is live. That is LSP risk, not custody of the UTXO.
If a Spark wallet cannot show you a unilaterally broadcastable exit tx from the seed alone, it is not in the same category as a channel you opened. "No liquidity to manage" is the product. Unilateral exit is the property. They are not the same sentence.