Zcash Ditches Trusted Setup With Halo 2 System

Zcash's Halo 2 system has replaced the need for a trusted setup in its zero-knowledge proof system, allowing users to verify private transactions without relying on a secret ceremony.

The change was implemented with the Orchard shielded pool in May 2022 and has undergone a real-world stress test. In late May 2026, a flaw was discovered in the Orchard circuit, which was subsequently patched by developers.

Zcash-Halo 2 is an open-source code developed by Electric Coin Company that enables zero-knowledge proofs without requiring a trusted setup ceremony. It uses recursive proof composition to avoid secret starting parameters and has undergone formal verification and auditing.