Wormhole's Circle Integration smart contracts enable composable cross-chain transfers of Circle supported assets by pairing Circle's [Cross-Chain Transfer Protocol](https://www.circle.com/en/pressroom/circle-enables-usdc-interoperability-for-developers-with-the-launch-of-cross-chain-transfer-protocol) with Wormhole's generic-messaging layer.
[Foundry tools](https://book.getfoundry.sh/getting-started/installation), which include `forge`, `anvil` and `cast` CLI tools, are a requirement for testing and deploying the Circle Integration smart contracts.
Currently, Circle's [Cross-Chain Transfer Protocol](https://www.circle.com/en/pressroom/circle-enables-usdc-interoperability-for-developers-with-the-launch-of-cross-chain-transfer-protocol) is only available for the Ethereum and Avalanche networks. Both of these chains are supported by Wormhole.
See the [Wormhole monorepo](https://github.com/wormhole-foundation/wormhole) for more information about the reference implementation of the [Wormhole protocol](https://wormholenetwork.com).