Two Starkware researchers broadcast a quantum resistant Bitcoin transaction on mainnet, in block 964199, using hash based one time signatures built from script opcodes that already exist.
No consensus change. No soft fork. Nobody had to ask Bitcoin Core for anything.
It is about five times the size of a normal transaction, so at fifty sats a byte it stings. At one sat a byte it is nothing. And if the alternative is being quantum vulnerable, that is a price worth paying.
The headline is not the cost. It is that this was possible the whole time.
https://ungovernable.network/shows/bitcoin-brief/the-ai-pocalypse-continues/
Ungovernable
npub1jc…n2890
2026-09-02 22:00:00 UTC
Author Public Key
npub1jcympy69pht7ptan39se4nd09e4q66qhey649uu3rczm2zh88c7s0n2890Seen on
wss://offchain.pubPublished at
2026-09-02 22:00:00 UTCEvent JSON
{
"id": "1b8103a002cae5d2e0ed7e5d92e8ede490c634217f1f7bd4b7be79d60f38299d",
"pubkey": "9609b093450dd7e0afb389619acdaf2e6a0d6817c93552f3911e05b50ae73e3d",
"created_at": 1788386400,
"kind": 1,
"tags": [],
"content": "Two Starkware researchers broadcast a quantum resistant Bitcoin transaction on mainnet, in block 964199, using hash based one time signatures built from script opcodes that already exist.\n\nNo consensus change. No soft fork. Nobody had to ask Bitcoin Core for anything.\n\nIt is about five times the size of a normal transaction, so at fifty sats a byte it stings. At one sat a byte it is nothing. And if the alternative is being quantum vulnerable, that is a price worth paying.\n\nThe headline is not the cost. It is that this was possible the whole time.\n\nhttps://ungovernable.network/shows/bitcoin-brief/the-ai-pocalypse-continues/\n\nhttps://video.nostr.build/817eca93f3e4c099a84c86719edb983c71af913583936c672a523d913419662e.mp4",
"sig": "2ba9177d485d7d7f764aff2ec31f4b21149152bdfa3dcaa4bb1bdd6f2d285e045bdef8499ce6f5d965b34561ba6db171be213b2ca52729b4b1d113a1dcf6c63c"
}