{"type":"rich","version":"1.0","author_name":"npub1wtx5qvewc7pd6znlvwktq03mdld05mv3h5dkzfwd3dc30gdmsptsugtuyn","author_url":"https://nostr.ae/npub1wtx5qvewc7pd6znlvwktq03mdld05mv3h5dkzfwd3dc30gdmsptsugtuyn","provider_name":"njump","provider_url":"https://nostr.ae","html":"📅 Original date posted:2018-05-17\n📝 Original message:ZmnSCPxj via bitcoin-dev \u003cbitcoin-dev at lists.linuxfoundation.org\u003e writes:\n\n\u003e Good morning Rusty and list,\n\u003e\n\u003e\u003e Your zero-val-OP_TRUE-can't-be-spent-after-same-block SF is\n\u003e\u003e interesting,\n\u003e\u003e \n\u003e\u003e but if we want a SF just give us SIGHASH_NOINPUT and we'll not need\n\u003e\u003e this\n\u003e\u003e \n\u003e\u003e at all (though others still might).\n\u003e\n\u003e We might still want this in general in Lightning; for instance we\n\u003e could make every funding transaction include such an output.  If it\n\u003e turns out, our initial feerate estimate for the funding transaction is\n\u003e low, we can use the `OP_TRUE` for fee-bumping.  This is a win for\n\u003e Lightning since the funding transaction ID remains the same (even in\n\u003e Decker-Russell-Osuntokun, the trigger transaction is signed with\n\u003e `SIGHASH_ALL`, and refers to a fixed funding transaction ID).\n\u003e\n\u003e Without the `OP_TRUE`-for-fee-bump, we would have to pretend to open a\n\u003e new different channel and RBF the old funding transaction with a new\n\u003e higher-feerate funding transaction, then keep track of which one gets\n\u003e confirmed deeply (there is a race where a miner discovers a block\n\u003e using the older funding transaction before our broadcast of the new\n\u003e funding transaction reaches it).\n\u003e\n\u003e (we could also feebump using the change output of the funding\n\u003e transaction, but such a change output might not exist for all funding\n\u003e transactions.)\n\nThis would only really help in the case of the funding tx not having a\nchange output, which I believe will be very rare. In the case of a\nchange output we can simply do a CPFP which includes the change output."}