# Module BSV::Wallet::Txid <a id="module-BSV-Wallet-Txid"></a>

Canonical wtxid (wire-order binary) → dtxid (display-order hex) conversion,
exposed as a refinement so call sites read <code>wtxid.to_dtxid</code> rather
than re-deriving +reverse.unpack1('H*')+.

A refinement, not a global `String` patch: activate it per file with +using
BSV::Wallet::Txid+ and it applies only within that file's lexical scope. Gem
consumers (and any code that doesn't opt in) see a vanilla `String` — no
surprise +String#to_dtxid+ leaking into a host application.

No length validation: the inputs are trusted internal 32-byte wtxids (Sequel
`bytea` columns, SDK +Tx#wtxid+), and several call sites are inside
+BSV.logger&.debug+ blocks where a raise would be worse than a malformed log
line. Use <code>BSV::Primitives::Hex.validate_wtxid!</code> at the boundaries
that actually need to reject bad input.

See the wtxid/dtxid convention in CLAUDE.md.