# What is zkopru?

Zkopru is a layer-2 scaling solution for private transactions using zk-SNARK and optimistic rollup. It supports private transfer and private atomic swap within the layer-2 network between ETH, ERC20, ERC721 at a low cost. Also, with the pay-in-advance feature, users can withdraw assets from the layer-2 before the finalization.

![zkopru-banner](https://790000186-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MBKrJqCGjfj63_Y1Run%2F-MBKsNkMQdJd7mNJPgub%2F-MBKsdVU_eDh-aR8THEP%2Fzkopru%20banner\(2\).png?alt=media\&token=a3b184d6-caef-49b9-b08f-b143d1aa6003)