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Bridge

Bridge

Twin's bridge lets you move any token between the supported networks with no custodians and no liquidity pools. It is built on LayerZero V2 using the OFT (Omnichain Fungible Token) standard.

Model: burn & mint

Unlike a lock & mint bridge (which locks funds in a source contract), Twin uses burn & mint:

1. The user calls send() on the source network's adapter.
2. The adapter burns the tokens on the source network.
3. LayerZero carries the message to the destination network.
4. The destination adapter mints the same amount to the recipient.

Total supply is preserved: what is burned on one network is minted on the other. There is no insufficient-liquidity risk.

OFT interface

Each adapter exposes the standard LayerZero OFT interface. The two key functions to integrate:

Code
// Quote the native fee (gas for the LayerZero message)
function quoteSend(SendParam calldata _sendParam, bool _payInLzToken)
    external view returns (MessagingFee memory);

// Execute the cross-chain transfer (payable: pays the nativeFee)
function send(SendParam calldata _sendParam, MessagingFee calldata _fee, address _refundAddress)
    external payable returns (MessagingReceipt memory, OFTReceipt memory);

Code
struct SendParam {
    uint32  dstEid;        // destination network EID
    bytes32 to;            // recipient (address left-padded to bytes32)
    uint256 amountLD;      // amount to send (local decimals)
    uint256 minAmountLD;   // minimum accepted at destination (slippage)
    bytes   extraOptions;  // execution options ('0x' when enforcedOptions are set)
    bytes   composeMsg;    // '0x' for simple transfers
    bytes   oftCmd;        // '0x'
}

Integration flow

1. Approve — the user approves the adapter as spender of the ERC-20 (a prior transaction).
2. quoteSend — quote the nativeFee (message gas).
3. send — execute with msg.value = nativeFee. The wallet must be connected to the source network.

Adapters per network

Each token has one adapter per network. All LayerZero peers are wired bidirectionally between the 4 networks (verified on-chain via peers()), so any pair of networks is a valid route for all 10 tokens.

Base · EID 30184

Token	Adapter
ARGt	0xe80Af1d12426dB4394b147e04f179a38e7C5Dfe7
BRAt	0xE6C8538962b5f75B3f4733aCE5640cd14D15D05a
MEXt	0x25Ea0F5832Cde4167Ba0C20FEB6d4e0ED2A1B6EE
COLt	0xb560fC4F5B550f798F29F74D47484af8CF9947b4
PERt	0x2D1888C2Db109876857bACAdadA56E0d5d37d913
CHLt	0x3231629ea5D9BfC3aE52Da01b65662556E919031
BOLt	0xae4f231D0D2ddd60Fe5356320CDf9C70A3a8dE15
PRYt	0xb43f5ebEA27a5c1950fB0214546F8fB538A5B9d9
URYt	0xDE3Fb54eF5b5C744f737c22084C5C7Fac3017a4c
VENt	0x67639776959A4b80Af42dE086DC57F3c17E50ed7

Polygon · EID 30109

Token	Adapter
ARGt	0xD70ad085684b2A9f4B5d54D7BDB2ecA37a273216
BRAt	0xdd69780d3705011411BCE40A4bC88B32e2412A7E
MEXt	0x458eC13750aeb52DC6D13adE9050a406d26BC123
COLt	0x8De321951074d8e3E42Bd8f82f93901Ad94618E1
PERt	0xd2e9Fa14FF9DA560ebc1A928793C9AD263a2b85F
CHLt	0x4E2dD4752C261CBAb40Ac8641ED4bb920B5fA878
BOLt	0x19706Fc31ef62a532C67E32F1C4723d7fDdA770b
PRYt	0xAfC84148Da0694ECDf7e32a68c613756d0C6B452
URYt	0xaC29533bEaBe2562d278cffB7f9DDA81CEbaA5C4
VENt	0xC0921B98D69eC36261B96eE82c5Be7c8dBf2d050

Arbitrum · EID 30110

Token	Adapter
ARGt	0x4821FBf47B261F0D52Ba0F941CF67b8648f82691
BRAt	0xC08b9BB6758287a4F4db150c56537Dd4b1e79F54
MEXt	0x8eDCB5019E27e58b6108A0128849F5fAeeFF7023
COLt	0xE9c1eD112c6eB25020996cCc0B8bEF1102Dd9221
PERt	0x0Fb3458954b2Fda00e8819F4227BFBa4BA581bDe
CHLt	0x34F3913D013444cBF8beE7BF42E4cDF11Cd8F7A7
BOLt	0xfE8c8568a3f918e0F79C53A6678B53359a987003
PRYt	0xDDfD8e02E093b6c82d132ee8Eb4257622c661EF0
URYt	0xC11c33CBFc367cF6a81885B7D86e7ab207Aec75E
VENt	0xB2268f9FF80b9009a7eA4aE2fcF77277F114E8b3

Ethereum · EID 30101

Token	Adapter
ARGt	0x5Eaa8760c3290eb78A2BE5E33b6696bE42e47DD9
BRAt	0xA91f0Ca6fECd536B50DF1b24391aC6714a6711ff
MEXt	0xE9c1eD112c6eB25020996cCc0B8bEF1102Dd9221
COLt	0x932e9A0C0A1E8356cC96e01084245bfA348293F1
PERt	0xE6eeCb4fe20f150a4a5a703b83517C3C3cdF386D
CHLt	0x0dc743a47D46a99512D816b2aAfE18C8Bcc7F807
BOLt	0x974189a3ceBb301FADBA0a561f262228FC370CB4
PRYt	0xF357b551d7FA095c3a0D184831Ccf990538FCDDD
URYt	0x6bDdaceCc407161d4876FD73b89ca096b9A49BA8
VENt	0x89757E24C6621c253528c70C192ee51Ce48869b0

Using the bridge from the app

End users don't need to interact with the contracts directly: the Twin app exposes the bridge with token selection, source/destination network and automatic fee quoting.