COTI has launched the testnet for COTI Nightfall, an Ethereum Zero-Knowledge (ZK) Roll-up joining the COTI ecosystem as an enterprise-grade privacy layer.

Nightfall was originally built by Ernst & Young in 2019 and released to the public domain, later upgrading to a full ZK Roll-up architecture in 2025 for near-instant finality.

The latest iteration, Nightfall 4, supports private transfers across ERC-20, ERC-721, ERC-1155, and ERC-3525 token standards, with decentralized permissioning and KYC-gating built in for regulated environments.

Rather than replacing COTI's existing Garbled Circuits (GC) mainnet, Nightfall adds a second privacy layer, creating a dual-mainnet stack:

1️⃣ GC Mainnet — fast, low-cost, scalable; built for DeFi, payments, identity, and AI applications

2️⃣ Nightfall ZK — enterprise-grade, compliance-ready privacy for institutional workflows, tokenized RWAs, and regulated payments

The COTI token will be native to both chains, bridged 1:1, with a fixed max supply and no new token minting, unifying fees, staking, governance, and privacy services across both networks.