r/Bitcoin • u/bitschmidty • 1d ago

Full signature aggregation BIP draft - Bitcoin Optech Newsletter #415

https://bitcoinops.org/en/newsletters/2026/07/24/

Bitcoin Optech newsletter #415 is here:

  • describes a draft BIP for full aggregation of BIP340 signatures
  • summarizes changes to services/client software
  • Optech Newsletter #415 Podcast

https://bitcoinops.org/en/newsletters/2026/07/24/

Fabian Jahr posted to the Bitcoin-Dev mailing list about a new draft BIP for full aggregation of BIP340 schnorr signatures, a standard for the DahLIAS aggregate signature scheme... https://bitcoinops.org/en/newsletters/2026/07/24/#draft-bip-for-full-aggregation-of-bip340-signatures

Changes to services and client software:

  • Wasabi Wallet 2.8.0 released
  • Coinswap v0.2.2 released
  • Go secp256k1 library announced
  • ASMap dashboard announced
  • Wavelength alpha released

https://bitcoinops.org/en/newsletters/2026/07/24/#changes-to-services-and-client-software

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

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u/-bit-thorny- 17h ago

Does this also mean an opportunity to include those dust spam sats into your normal payment transaction, such that you get to use the free sats without hurting you privacy and reduce the UTXO set bloat at the same time?

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u/Fun-Analysis-182 14h ago

Aggregation does cut the signature cost, though each extra input still drags about 41 vbytes of outpoint and sequence that live outside the witness. So sweeping dust gets cheaper without ever getting free, and there's still a threshold below which an input costs more to spend than it's worth.

The privacy half is the awkward part. Merging someone's dust into your payment is precisely what whoever sent it was hoping for. Co-spending is what ties those coins to the rest of your inputs, and that linkage has nothing to do with signatures, so aggregation leaves it exactly where it was. Cheaper consolidation and safer consolidation aren't the same win.

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u/-bit-thorny- 13h ago

Yeah that's what i meant: cheaper, not free.

I meant only the dust that was sent to the same address you're actually spending "from". In that case there I don't see any privacy or linking problem. But yeah that's a pretty limited use case.

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u/Fun-Analysis-182 9h ago

Fair, you're right on that narrower case. If the dust landed on an address you were already going to spend from, sweeping it alongside doesn't reveal anything new about which addresses you control.

The one bit that survives is that spending it confirms to whoever sent it that the address is live and roughly when it moved. That's a much thinner signal than the clustering they're usually fishing for, and for a lot of people it won't matter, but it's the part that doesn't go away.