Yearn Stake the Bridge

Structure

Role Manager

• Yearn governed contract to handle vault deployments and configuration

L1 Deployer

• The L1 rollup admin will register their rollup with the L1 Deployer

  • registerRollup

    • rollupID
    • L1 EscrowManager
    • L2 Deployer

  • Deploys a new vault if not yet, does full setup.

  • Deploys L1 escrow and sends message to bridge to L2 escrow.

• Allows anyone to add a new asset to any registered Rollup

  • newEscrow
    • rollupID
    • L1 Token

• Allows for a Rollup Admin to add custom vaults for a specific asset.

  • newCustomVault
    • rollupID
    • L1 Token
    • Vault (Optional)

• Allows for a Rollup Admin to update is EScrow Manager or L2 Deployer

L2 Deployer

• Receives message from L1 Deployer when a new escrow was created for a new asset.
• Deploys L2 Token, Escrow and convertor and completes setup
• Owned by L2 Admin

L1 Yearn Escrow

• Yearn specific L1 Escrow contract that handles bridge transactions.

• Will deposit funds into a Yearn vault during a bridge if amounts are over any set minimumBuffer

• If withdraws cannot be processed it will send shares to users when bridging back to L1.

• Rollups Admin can update the minimumBuffer as well as the vault it uses.

• Allows for permissionless rebalance's based on the minimumBuffer.

Deployments

L1 Deployer: 0x1316a3312CfF738aDCBF011bCE9D1e7B9C88C817 STB Role Manager: 0x51b76329d2C6b8974053C9655484e231f7dcd418

In order to integrate your Polygon CDK chain with STB you will need to

1. Deploy an L2Deployer on your rollup.
2. Register the rollup and the L2 Deployer address with the L1 Deployer.

Once done it is permsissionless for anyone to use the STB to bridge from mainnet to your rollup.

There is a pre-built script that can be run from this repo in order to complete the full setup.

NOTE: The script assumes the rollups admin on the L1 is a Gnosis Safe and the private key input maps to either a singer or a delegate of that safe in order to post the txn that registers the rollup.

$ git clone --recursive https://github.com/yearn/yearn-stb

$ cd yearn-stb

$ cp .env.example .env

Fill in the full .env with your specific rollup RPC, Polygon CDK based rollup ID, and the desired addresses.

NOTE: To deploy a L2 Deployer during the script leave the L2_DEPLOYER variable as address(0). If one is already deployed, insert the address in that variable to not re-deploy.

To just deploy the L2 Deployer and not send the registerRollup Safe txn put 0 as the ROLLUP_ID.

If you have not added a keystore private key to foundry before add your address to use

$ cast wallet import --interactive <wallet_name>

Run the script

$ make register account=<wallet_name> sender=<wallet_address>

If successful the txn will both deploy the L2 Deployer on the specified rollup and post a Safe txn to register the Rollup in the L1 Deployer.

Verification

The L2 Deployer will deploy 3 other implementation contracts with it when deployed.

You can find the flatten version of all contracts deployed on the L2 in the repo https://github.com/yearn/yearn-stb/tree/master/flat

The encoded constructor arguments used for the L2 deployer should be logged in the console on deployment as well.

Foundry Documentation

https://book.getfoundry.sh/

Usage

Build

$ make build

Test

$ make tests

Trace

$ make trace

Gas Snapshots

$ make snapshot

Cast

$ cast <subcommand>

Help

$ forge --help
$ anvil --help
$ cast --help