Bitcoin Optech newsletter #361 is here:

Olaluwa Osuntokun posted to Delving Bitcoin about allowing nodes to use separate connections for relaying onion messages than they use for relaying HTLCs... https://bitcoinops.org/en/newsletters/2025/07/04/#separating-onion-message-relay-from-htlc-relay

Developers continued a previous discussion about the benefits of OP_CHECKTEMPLATEVERIFY (CTV), OP_CHECKSIGFROMSTACK (CSFS), or both together for various deployed and imagined protocols... https://bitcoinops.org/en/newsletters/2025/07/04/#ctv-csfs-advantages-for-ptlcs

Sjors Provoost posted to Delving Bitcoin to discuss how the recovery information for a wallet using vaults could be specified using an output script descriptor... https://bitcoinops.org/en/newsletters/2025/07/04/#vault-output-script-descriptor

Developers continued the previous discussion about how the availability of OP_CHECKTEMPLATEVERIFY (CTV) and OP_CHECKSIGFROMSTACK (CSFS) opcodes could “reduce [BitVM] transaction sizes by approximately 10x” and allow non-interactive peg-ins... https://bitcoinops.org/en/newsletters/2025/07/04/#continued-discussion-about-ctv-csfs-advantages-for-bitvm

James O’Beirne posted an open letter to the Bitcoin-Dev mailing signed by 66 individuals (as of this writing), many of them contributors to Bitcoin-related projects... https://bitcoinops.org/en/newsletters/2025/07/04/#open-letter-about-ctv-and-csfs

Developer Conduition posted to the Bitcoin-Dev mailing list a prototype implementation that uses the proposed OP_CAT opcode and other Script instructions to allow quantum-resistant signatures using the Winternitz protocol to be verified by consensus logic... https://bitcoinops.org/en/newsletters/2025/07/04/#op-cat-enables-winternitz-signatures

Tadge Dryja posted to the Bitcoin-Dev mailing list a method for allowing individuals to spend UTXOs using quantum-vulnerable signature algorithms even if fast quantum computers would otherwise allow redirecting (stealing) the output of any attempted spend... https://bitcoinops.org/en/newsletters/2025/07/04/#commit-reveal-function-for-post-quantum-recovery

Steven Roose posted to Delving Bitcoin about a variation on OP_TXHASH called TXSIGHASH that extends 64-byte schnorr signatures with additional bytes to indicate what fields in the transaction (or related transactions) the signature commits to... https://bitcoinops.org/en/newsletters/2025/07/04/#op-txhash-variant-with-support-for-transaction-sponsorship

Bitcoin Optech will host an audio recap discussion of this newsletter on Riverside.fm Tuesday at 16:30 UTC. Join us to discuss or ask questions! https://riverside.fm/studio/bitcoin-optech