NEAR Omni Bridge

The Omni Bridge is a multi-chain asset bridge that facilitates secure and efficient asset transfers between different blockchain networks. It leverages Chain Signatures and it's decentralized Multi-Party Computation (MPC) service to ensure trustless and decentralized cross-chain asset transfers.

For more information on how it works, please see Omni Bridge Documentation.

Supported Networks

NEAR → Foreign Chain: All outbound transfers use Chain Signatures (MPC).

Foreign Chain → NEAR: Inbound transfers are verified using:

• Ethereum, Bitcoin, Zcash: Light clients
• Solana, BNB and EVM L2s (Base, Arbitrum, Polygon): Wormhole

Contract Addresses

Mainnet Addresses

Bridge Contracts:

• Arbitrum: 0xd025b38762B4A4E36F0Cde483b86CB13ea00D989
• Base: 0xd025b38762B4A4E36F0Cde483b86CB13ea00D989
• Bnb: 0x073C8a225c8Cf9d3f9157F5C1a1DbE02407f5720
• Polygon: 0xd025b38762B4A4E36F0Cde483b86CB13ea00D989
• Ethereum: 0xe00c629aFaCCb0510995A2B95560E446A24c85B9
• NEAR: omni.bridge.near
• Solana: dahPEoZGXfyV58JqqH85okdHmpN8U2q8owgPUXSCPxe

Helper Contracts:

• NEAR:
  • vaa-prover-0_4_3.bridge.near
  • vaa-prover-0_4_1.bridge.near
  • eth-prover-0_4_1.bridge.near
  • omdep.near
  • factory.bridge.near

Testnet Addresses

Bridge Contracts:

• Arbitrum: 0x0C981337fFe39a555d3A40dbb32f21aD0eF33FFA
• Base: 0xa56b860017152cD296ad723E8409Abd6e5D86d4d
• Bnb: 0xEC81aFc3485a425347Ac03316675e58a680b283A
• Polygon: 0xEC81aFc3485a425347Ac03316675e58a680b283A
• Ethereum: 0x68a86e0Ea5B1d39F385c1326e4d493526dFe4401
• NEAR: omni.n-bridge.testnet
• Solana: Gy1XPwYZURfBzHiGAxnw3SYC33SfqsEpGSS5zeBge28p

Helper Contracts:

• NEAR:
  • eth-prover.n-bridge.testnet
  • vaa-prover.n-bridge.testnet
  • omnidep.testnet

Development Testnet Addresses

Bridge Contracts:

• Arbitrum: 0xd025b38762B4A4E36F0Cde483b86CB13ea00D989
• Base: 0x0C981337fFe39a555d3A40dbb32f21aD0eF33FFA
• Ethereum: 0x3701B9859Dbb9a4333A3dd933ab18e9011ddf2C8
• NEAR: omni-locker.testnet
• Solana: Gy1XPwYZURfBzHiGAxnw3SYC33SfqsEpGSS5zeBge28p

Helper Contracts:

• NEAR:
  • eth-prover.testnet
  • wormhole-prover-test.testnet
  • omdep.testnet

Transfer Times & Finality

Transfer Times Overview

NEAR → Other Chains

• Average processing time: ~30 seconds (MPC signatures)

Other Chains → NEAR

Current finality times:

• Solana: 14s
• Arbitrum: 1066s
• Base: 1026s
• Ethereum: 960s

Additional processing delays:

• OmniBridge transfers relayer: 2s
• Wormhole off-chain validators: 60s
• Ethereum blocks relayer: 60s

Token Operations

Logging Token Metadata

EVM API

function logMetadata(address tokenAddress) external

NEAR API

pub fn log_metadata(&self, token_id: &AccountId) -> Promise 

Solana API

pub fn log_metadata(ctx: Context<LogMetadata>) -> Result<()>

Using CLI

cargo run mainnet omni-connector log-metadata --token base:0x<TOKEN_ADDRESS> --base-private-key <KEY>

Using SDK-JS

import { getClient } from "omni-bridge-sdk";

// Initialize client for source chain
const client = getClient(ChainKind.Near, wallet);

// Example: Deploy NEAR token to Ethereum
const txHash = await client.logMetadata("near:token.near");
console.log(`Metadata logged with tx: ${txHash}`);

Deploying Tokens

EVM API

function deployToken(bytes calldata signatureData, BridgeTypes.MetadataPayload calldata metadata) payable external returns (address)

NEAR API

pub fn deploy_token(&mut self, #[serializer(borsh)] args: DeployTokenArgs) -> Promise

Solana API

pub fn deploy_token(ctx: Context<DeployToken>, data: SignedPayload<DeployTokenPayload>)

Using CLI

cargo run mainnet omni-connector deploy-token --chain <ChainKind> --source-chain <ChainKind> --tx-hash <LogMetadataTxHash> --base-private-key <KEY>

Binding Tokens (NEAR-specific)

Only needed for NEAR tokens that have been deployed on other chains. This action is typically applied automatically by the relayer.

NEAR API

pub fn bind_token(&mut self, #[serializer(borsh)] args: BindTokenArgs) -> Promise

Transfer Operations

Initiating Transfers

Transfers require a fee, which can be paid in either:

1. The transferred token
2. Native chain token (e.g., ETH, SOL)

Note: On NEAR, it isn't possible to attach a deposit in the ft_transfer_call, so the native fee should be attached by a separate call to the storage deposit

EVM API

// 1. Approve tokens
function approve(address spender, uint256 amount)

// 2. Initiate transfer
function initTransfer(
    address tokenAddress,
    uint128 amount,
    uint128 fee,
    uint128 nativeFee,
    string calldata recipient,
    string calldata message
) payable external

NEAR API

// 1. Storage deposit
pub fn storage_deposit(&mut self, account_id: Option<AccountId>) -> StorageBalance

// Helper functions
pub fn required_balance_for_account(&self) -> NearToken
pub fn required_balance_for_init_transfer(&self) -> NearToken

// 2. Transfer
fn ft_transfer_call(&mut self, receiver_id: AccountId, amount: U128, memo: Option<String>, msg: String) -> PromiseOrValue<U128>

Solana API

// For SPL tokens
pub fn init_transfer(ctx: Context<InitTransfer>, payload: InitTransferPayload) -> Result<()>

// For native SOL
pub fn init_transfer_sol(ctx: Context<InitTransferSol>, payload: InitTransferPayload) -> Result<()>

Fee Provider & Status API

API Details

API Endpoints:

• Mainnet: https://mainnet.api.bridge.nearone.org/api/v1
• Testnet: https://testnet.api.bridge.nearone.org/api/v1
• OpenAPI Specification

Note: Custom relayers can process transfers with zero fees.

SDKs & Tools

• Bridge SDK (Rust)
• Bridge SDK (JavaScript)

Get Involved

We welcome contributions from the community! The code is open source and there are many ways to make meaningful contributions.

Key Areas for Contribution

• Chain Integrations: Help expand support for new blockchain networks
• Performance Optimization: Improve transaction speeds and efficiency
• Security Analysis: Strengthen the security infrastructure
• Developer Tools: Build better tooling and documentation

Bridge infrastructure is a fundamental component of a multi-chain future. Through Chain Signatures, we're creating a more efficient, secure, and scalable approach to cross-chain communication.

Join us in building the future of cross-chain interoperability!