Halo Arc, invented and developed at Electric Coin Company (ECC) with the support of the Ethereum Foundation, includes updates to Zcashd (Zcash’s consensus node software), an ECC wallet prototype and the ECC wallet software development kits (SDK). Perhaps the most notable change to the wallet software is the change to its privacy setting. Whereas users previously needed to opt in to shielding their transactions, the upgrade will now enable privacy-protecting, shielded-by-default transactions.