causeway-btc

Off-chain helpers for using Causeway with Bitcoin (testnet4 / mainnet).

Public surface

• address::derive_btc_address(...) — re-export of causeway_derive::btc::derive_btc_address. P2TR vault address.
• tx::build_unsigned_tx(...) — Taproot key-spend sighash for the single-input single-output tx the M1.0 pipeline supports.
• sign::assemble_signed_tx(...) — splice the 64-byte Schnorr signature into the input-0 witness.

Status

Alpha. M1.0 pipeline shape: single-input, single-output, key-spend Taproot. No multi-input UTXO selection, no fee estimation. Tested on testnet4.