K17 addendum 2: escrow top-up on the state-advancing cycle and a third-party funder protocol for a UTXO-chained stack machine

Inventor(s)

• Jerry D. ChanFollow

Abstract

This second addendum to the K17 disclosure (Technical Disclosure Commons, October 20, 2026) describes three mechanisms that let any party add value to a running stack machine whose suspended process lives in one unspent transaction output. First, an escrow top-up on the state-advancing cycle: the cycle method takes a topUp argument, the next machine output holds value minus reward minus payout plus topUp, pinned by the output hash, and extra inputs from any party pay for it; a cycle that produces no next state (HALT, any fault, the dead-man halt, an unaffordable payout) must carry a zero top-up, so a top-up never reaches the beneficiary through a refund, and a top-up never moves the machine clock, so money alone cannot change the reward auction or the dead-man deadline. Second, a self-funded top-up in the keeper that applies once, is dropped on a halting cycle, and is never added twice after a send with an unknown result. Third, a third-party funder protocol (offer, request, sign, complete) in which the keeper signs a final cycle transaction with one unsigned funder input and the funder, before it signs, follows the machine forward from a trusted outpoint, refuses a second input on its key, requires a push-only minimal unlocking script with the exact ABI push count, runs the script interpreter against the real prevout and replays the cycle exactly. Prior art (sCrypt faucets, Chainlink addFunds, PSBT, payjoin and BOLT 2 interactive transactions) is acknowledged, measurements of the reference implementation are given, and 26 alternative embodiments are described.

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.

Recommended Citation

Chan, Jerry D., "K17 addendum 2: escrow top-up on the state-advancing cycle and a third-party funder protocol for a UTXO-chained stack machine", Technical Disclosure Commons, (October 26, 2026)
https://www.tdcommons.org/dpubs_series/12417