Lightning Specification Meeting 2025/07/28

[t-bast]

The meeting will take place on Monday 2025/07/28 at 8pm UTC (5:30am Adelaide time) on Libera Chat IRC #lightning-dev. It is open to the public.

A video link is available for higher bandwidth communication: https://meet.jit.si/Lightning-Spec-Meeting

Recently Updated Proposals / Seeking Review

This section contains changes that have been opened or updated recently and need feedback from the meeting participants.

• Bolt 12 invoice test vector Update "invalid currency UTF-8" test vector  #1264
• Increase spent channel graph removal delay Increase channel close delay to 72 blocks #1270
• Attributable failures Attribution data (feature 36/37) #1044
• Receiver-side random delays Add recommendations for receiver-side random delays #1263
• Splicing Channel Splicing (feature 62/63) #1160
• Dual funding reconnect commit_sig retransmission Do not unnecessarily retransmit commitment_signed in dual funding #1214
• Allow non-initiator to RBF dual-funded channels Allow either node to send tx_init_rbf in v2 establishment #1236
• Taproot extension-bolt: simple taproot channels (feature 80/81) #995
• Taproot gossip extension-bolt: taproot gossip (features 70/71/72/73/74/75) #1059
• Channel jamming draft: HTLC Endorsement to Mitigate Channel Jamming #1071 Project Updates: Hybrid Channel Jamming Mitigation #1218
• Trampoline routing Trampoline Routing (2021 edition) (Feature 56/57) #829 and Trampoline onion format (Feature 56/57) #836
• Async payments Support async payments in BOLT 12 #1149
• Path queries Path queries (feature 66/67) #1259
• BOLT 12 recurrence BOLT 12: re-add recurrence support. #1240
• Bolt 12 contacts: blip-0042: Bolt 12 Contacts blips#42
• Liquidity ads Extensible Liquidity Ads #1153
• Dynamic Commitments Extension/dynamic commitments #1117
• 0-fee commitments Zero-fee commitments using v3 transactions (feature 40/41) #1228

Stale Proposals

This section contains pending changes that may not need feedback from the meeting participants, unless someone explicitly asks for it during the meeting. These changes are usually waiting for implementation work to happen to drive more feedback.

• Inbound fees Inbound routing fees blips#18 and Add a bLIP for backwards-compatible inbound fees blips#22

Waiting for interop

This section contains changes that have been conceptually ACKed and are waiting for at least two implementations to fully interoperate.
They most likely don't need to be covered during the meeting, unless someone asks for updates.

• Don't force close until error is received after channel_reestablish Nodes shouldn't publish their commitment when receiving outdated channel_reestablish #934
• Zero reserve Add option_zero_reserve (FEATURE 64/65) #1140 (follow-up on bolt2: relax channel_reserve_satoshis requirements #1133 to include a feature bit)

Long Term Updates

This section contains long-term changes that need review, but require a substantial implementation effort.

• Simplified commitment Feature 106/107: option_simplified_update. #867
• lnprototest (https://github.com/rustyrussell/lnprototest)
• Investigate QUIC transport BOLT-0008+BOLT-0007: consider adding QUIC transport #1257

[tnull]

@t-bast As we merged the LDK implementation last week, could we add lightning/blips#55 to the agenda?

[Roasbeef]

Will miss this one. On my end awaiting feedback re the taproot related spec updates I recently pushed out.

[t-bast]

@Roasbeef we've just added some comments to the spec after doing a first round of compat tests between eclair and lnd!