PISA, the first working prototype combining Payjoin with Cross Input Signature Aggregation (CISA), was just demoed by (fjahr) of Brink and the Payjoin Dev Kit team at Lugano Plan.
CISA would make collaborative bitcoin transactions like Payjoins and Coinjoins smaller and cheaper on-chain, and this demo shows the two working together for the first time.
TFTC
npub1sk…6jraw
2026-10-23 15:21:53 UTC
Author Public Key
npub1sk7mtp67zy7uex2f3dr5vdjynzpwu9dpc7q4f2c8cpjmguee6eeq56jrawPublished at
2026-10-23 15:21:53 UTCEvent JSON
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"content": "PISA, the first working prototype combining Payjoin with Cross Input Signature Aggregation (CISA), was just demoed by (fjahr) of Brink and the Payjoin Dev Kit team at Lugano Plan.\n\nCISA would make collaborative bitcoin transactions like Payjoins and Coinjoins smaller and cheaper on-chain, and this demo shows the two working together for the first time.\nhttps://blossom.primal.net/31905bdb787caf39ae0be25b661ead1fad9ef91324514b368eac227790aa07a3.mp4",
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