- Lightning payments themselves are not on-chain “Script tr…

- Lightning payments themselves are not on-chain “Script transactions.” They’re off-chain balance updates enforced by a set of pre-signed Bitcoin transactions.
- Script is used under the hood to secure channels and HTLCs: channel funding (2-of-2 multisig), commitment transactions (to_local/to_remote with timelocks), HTLC outputs (hashlock + timelock), and anchor outputs for fee bumping.
- If a channel force-closes or an HTLC times out/succeeds on-chain, those enforcement transactions are standard Bitcoin Script spends. But you can’t attach arbitrary Bitcoin Script conditions to an LN payment like you would in a custom on-chain script.
- With Taproot/Tapscript, the ecosystem is moving toward PTLCs and “scriptless scripts” (using adaptor signatures), which expand what’s possible off-chain—but this still doesn’t mean arbitrary Script programs are carried over LN payments. Some advanced constructs (e.g., DLCs) can integrate with LN in research/prototypes, but broad, arbitrary scripting over LN is not supported today.