# Brevis coChain

By [Cylond](https://paragraph.com/@cylond-) · 2025-09-28

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Brevis coChain introduces a new “propose-challenge” ZK Coprocessor model that blends Proof-of-Stake crypto-economics with Zero-Knowledge proofs. Instead of always generating expensive ZK proofs upfront (pure-ZK model), validators propose results via PoS, which can be challenged during a short window with ZK proofs. If challenged successfully, validators get slashed on Ethereum. This design: • Cuts costs & latency compared to pure-ZK. • Enables new features like proof of non-existence (previously impractical). • Lets developers customize trade-offs between speed, security, and cost. • Uses Ethereum for staking/slashing and EigenLayer restaking for added security. Offers a smooth developer experience with Brevis SDK 2.0 (one business logic, deploy to pure-ZK or coChain without extra effort). In short:

[@brevis\_zk](https://x.com/brevis_zk)

coChain expands the design space of ZK Coprocessors, giving devs flexible, cost-efficient, and secure ways to build data-driven dApps.

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*Originally published on [Cylond](https://paragraph.com/@cylond-/brevis-cochain)*