<oembed><type>rich</type><version>1.0</version><title>ZmnSCPxj [ARCHIVE] wrote</title><author_name>ZmnSCPxj [ARCHIVE] (npub1g5…3ms3l)</author_name><author_url>https://njump.me/npub1g5zswf6y48f7fy90jf3tlcuwdmjn8znhzaa4vkmtxaeskca8hpss23ms3l</author_url><provider_name>njump</provider_name><provider_url>https://njump.me</provider_url><html>📅 Original date posted:2019-12-17&#xA;📝 Original message:&#xA;Good morning David, t-bast, and all,&#xA;&#xA;&#xA;&gt; I&#39;m not aware of any way to currently force single-show signatures in&#xA;&gt; Bitcoin, so this is pretty theoretical. Also, single-show signatures&#xA;&gt; add a lot of fragility to any setup and make useful features like RBF&#xA;&gt; fee bumping unavailable.&#xA;&#xA;With `OP_CAT`, we can enforce that a particular `R` is used, which allows to implement single-show signatures.&#xA;&#xA;    # Assuming signatures are the concatenation of (R,s)&#xA;    &lt;R&gt; OP_SWAP OP_CAT &lt;ACINQ&gt; OP_CHECKSIG&#xA;&#xA;The above would then feed `s` only on the witness stack.&#xA;&#xA;Regards,&#xA;ZmnSCPxj</html></oembed>