In Calimero we have implement what we call “The Realistic Bridge” - a bridge which is able to execute transfers and contract calls in “blockchain real time”, allowing you to move assets between NEAR public networks (Testnet and Mainnet) and your private shard, as well the ability to execute cross shard contract calls to execute: a) private smart contracts calls inside the shard from a public contract b) public smart contract calls from a contract inside the private shard. Our bridge is the fastest and most cost efficient bridge implemented in Web3 space till now. It also includes a permissions management contract providing you with the ability to set policies regarding which parties can communicate with the bridge and what type of interaction they are allowed to have, much like a firewall which controls incoming and outgoing connections. Check out our Github: https://github.com/calimero-is-near/bridge-contracts.