interop-sdk: cross-chain package

The cross-chain package provides a standardized interface for interacting with cross-chain bridges and protocols. It enables seamless token transfers and swaps between different blockchain networks through a unified API.

Key features:

• Cross-chain token transfers between supported networks
• Cross-chain token swaps with customizable slippage
• Quote fetching for cross-chain operations
• Standardized provider interface for integrating different bridge protocols
• Type-safe interactions with comprehensive TypeScript support

Setup

1. Install dependencies running pnpm install

Available Scripts

Available scripts that can be run using pnpm:

| Script | Description | | ------------- | ------------------------------------------------------- | | build | Build library using tsc | | check-types | Check types issues using tsc | | clean | Remove dist folder | | lint | Run ESLint to check for coding standards | | lint:fix | Run linter and automatically fix code formatting issues | | format | Check code formatting and style using Prettier | | format:fix | Run formatter and automatically fix issues | | test | Run tests using vitest | | test:cov | Run tests with coverage report |

Usage

import {
    AcrossProvider,
    createCrossChainProvider,
    createProviderExecutor,
    InteropAddressParamsParser,
    ProviderExecutor,
} from "@interop-sdk/cross-chain";

// Create a provider for a specific protocol (e.g., Across)
const provider = createCrossChainProvider("across");

// Get a quote for a cross-chain transfer
const quote = await provider.getQuote("crossChainTransfer", {
    sender: "0x...", // sender address (hex)
    recipient: "0x...", // recipient address (hex)
    inputTokenAddress: "0x...", // input token address
    outputTokenAddress: "0x...", // output token address
    inputAmount: "1000000000000000000", // amount in wei
    inputChainId: 11155111, // source chain ID
    outputChainId: 84532, // destination chain ID
});

// Simulate the open transaction for the quote
const txs = await provider.simulateOpen(quote.openParams);

// Batch quotes and execution using ProviderExecutor
const providers = [provider];
const executor = createProviderExecutor(providers);
const quotes = await executor.getQuotes("crossChainTransfer", {
    sender: "0x...",
    recipient: "0x...",
    inputTokenAddress: "0x...",
    outputTokenAddress: "0x...",
    inputAmount: "1000000000000000000",
    inputChainId: 11155111,
    outputChainId: 84532,
});

// Execute a quote (simulate open)
const txRequests = await executor.execute(quotes[0]);

// Using InteropAddressParamsParser for human-readable or binary addresses
const paramParser = new InteropAddressParamsParser();
const executorWithParser = createProviderExecutor(providers, { paramParser });
const quotesWithInterop = await executorWithParser.getQuotes("crossChainTransfer", {
    sender: "alice.eth@eip155:1#ABCD1234", // human-readable interop address
    recipient: "0x...", // hex address
    amount: "1000000000000000000",
    inputTokenAddress: "0x...",
    outputTokenAddress: "0x...",
});

API

Providers

• createCrossChainProvider(protocolName, config?, dependencies?) – Create a provider for a supported protocol (e.g., "across").
• CrossChainProvider (abstract class)
  • .getProtocolName() – Returns the protocol name.
  • .getQuote(action, params) – Fetch a quote for a cross-chain action ("crossChainTransfer" or "crossChainSwap").
  • .simulateOpen(openParams) – Simulate the open transaction for a quote.
  • .validateOpenParams(openParams) – Validate open parameters.

Provider Executor

• createProviderExecutor(providers, dependencies?) – Create an executor for batch quoting and execution.
• ProviderExecutor
  • .getQuotes(action, params) – Get quotes from all providers.
  • .execute(quote) – Simulate the open transaction for a quote.

Param Parsers

• InteropAddressParamsParser – Parses human-readable or binary interop addresses for use in cross-chain actions.
• ParamsParser (interface) – Custom param parsers can be implemented for advanced use cases.

Types

• GetQuoteParams<Action> – Parameters for quoting (see crossChainProvider.interface.ts).
• GetQuoteResponse<Action, OpenParams> – Quote response structure.
• BasicOpenParams, Fee, and more (see exported types).

Supported Actions

• crossChainTransfer – Transfer tokens between chains.
• crossChainSwap – Swap tokens across chains (if supported by the protocol).

References

• Viem Documentation - Low-level Ethereum interface used for transaction handling
• Zod Documentation - TypeScript-first schema validation used for input validation
• Cross-Chain Interoperability Standards - Overview of cross-chain bridge concepts

The current SDK uses Across on testnet for demo purposes only. Performance may not reflect mainnet behavior and is not representative of the final production experience