Consensus spec work, Onion message attack - Bitcoin Optech Newsletter #402

Bitcoin Optech newsletter #402 is here:

- describes work on a declarative executable specification of consensus rules
- summarizes a discussion about onion message jamming in the Lightning Network
- summarizes popular Q&A from Stack Exchange
- Optech Newsletter #402 Podcast
https://bitcoinops.org/en/newsletters/2026/04/24/

Toby Sharp posted to Delving Bitcoin and the Bitcoin-Dev mailing list an update on the Hornet node project...
https://bitcoinops.org/en/newsletters/2026/04/24/#hornet-node-s-declarative-executable-specification-of-bitcoin-consensus-rules

Erick Cestari posted to Delving Bitcoin about the onion message jamming problem affecting the Lightning Network...
https://bitcoinops.org/en/newsletters/2026/04/24/#onion-message-jamming-in-the-lightning-network

Selected Q&A from Bitcoin Stack Exchange
- Why did BIP342 replace CHECKMULTISIG with a new opcode, instead of just removing FindAndDelete from it?
- Does SIGHASH_ANYPREVOUT commit to the tapleaf hash or the full taproot merkle path?
- What does the BIP86 tweak guarantee in a MuSig2 Lightning channel, beyond address format?
https://bitcoinops.org/en/newsletters/2026/04/24/#selected-qa-from-bitcoin-stack-exchange

Bitcoin Optech will host an audio recap discussion of this newsletter streaming live on X/Twitter Tuesday at 16:30 UTC.