Halo Arc for Zcash proposed for release later this year

Note: This post has been updated to reflect the latest Zcash release schedule.


Electric Coin Co. (ECC) today announced Halo Arc for Zcash, a product suite to launch the next generation of Zcash. It includes updates to Zcashd, the ECC Reference Wallet apps and the ECC wallet SDKs.

Halo Arc leverages two upcoming Zcash improvements: Network Upgrade 5 (NU5) and unified addresses. The upcoming network upgrade will move Zcash from zk-SNARKs to the Halo proving system, removing the need for the trusted setup and upgrading the protocol’s underlying cryptography.

Unified addresses, a complementary feature, introduce a future-proof address format that prioritizes shielded adoption. Later this week, we’ll release a blog post with a deeper explanation of unified addresses, how they work and what it means for supporting Zcash users to shield by default.

The planned release of Halo Arc is January 2021*, to coincide with the activation of Network Upgrade 5 (NU5)**.

The Halo Arc product suite includes: 

  • ZCASHD, NU5-COMPATIBLE CONSENSUS NODE: Zcashd is the consensus node for Zcash. Zcashd will support the upcoming network upgrade, which includes the Orchard Shielded Protocol (ZIP 224), non-malleable transaction IDs (ZIP 244), a new transaction version format (ZIP 225), and unified addresses (ZIP 316).
  • ECC REFERENCE WALLET (iOS and Android): ECC Reference Wallet is a beta reference implementation of a Zcash wallet for Android and iOS, available as open source.
  • NU5-COMPATIBLE WALLET SDKS: ECC maintains wallet SDKs for Android and iOS. These SDKs will support the upcoming network upgrade, including a new transaction format, the Orchard shielded pool and unified addresses. 
    • AUTO-SHIELDING FEATURE: Auto-shielding lets users (more specifically their wallets) automatically move funds from a transparent address to the latest shielded ZEC pool. Auto-shielding, along with unified addresses, will facilitate increased user privacy and a better overall user experience. Through auto-shielding, wallets can offer their users funds that are shielded by default, regardless of the originating address. 
    • AUTO-MIGRATION FEATURE: Auto-migration is a mechanism for wallets to seamlessly move funds to the most modern shielded pool supported by the wallet. This feature will also make it easier to deprecate older pools.
    • IMPROVED NOTE MANAGEMENT: Improved note management reduces the time users need to wait between sending transactions. This means that lightclients will be able to send one transaction immediately after another.

Halo Arc represents a new ECC strategy, which bundles upgrades, products and features into regular releases. These bundles could include any or all of the products that ECC develops, such as Zcashd, Lightwalletd, wallet SDKs, and wallet source code.

As Zcash development decentralizes, the broader Zcash community will benefit from a greater diversity of products, such as the Zebrad consensus node from the Zcash Foundation and lightclient infrastructure funded by ZOMG. By emphasizing products as well as the underlying protocol, ECC can package and promote compatible software across the Zcash technology stack, from protocol to wallets.


 * Pending community approval
 ** A full timeline of the NU5 upgrade schedule can be found here.