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Welcome to Avail Nexus SDK

The Avail Nexus SDK is a powerful, headless TypeScript SDK designed for cross-chain operations, token bridging, swapping, and unified balance management. Built for backends, CLIs, and custom UI integrations, it enables seamless multi-chain interactions without the complexity.

Installation

Get started by installing the SDK with npm, yarn, or pnpm

Quick Start

Build your first bridge transaction in under 5 minutes

API Reference

Explore the complete API documentation and method signatures

Examples

Browse real-world examples and integration patterns

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Core Features

Cross-Chain Bridging

Move tokens seamlessly across 16+ supported blockchain networks with automatic route optimization

Cross-Chain Swaps

Execute EXACT_IN and EXACT_OUT swaps between any supported networks with best-price routing

Unified Balances

Aggregate user assets and balances across all connected chains in a single view

Smart Contract Execution

Call smart contracts with automatic bridging and funding logic built-in

Transaction Simulation

Estimate gas, fees, and required approvals before sending any transaction

Complete Testnet Coverage

Full multi-chain test environment for safe development and testing

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Why Choose Nexus SDK?

Built as a pure TypeScript library with no UI dependencies. Perfect for backends, CLIs, custom frontends, or any JavaScript environment.
Comprehensive TypeScript types, clear error messages, and detailed documentation make integration smooth and maintainable.
Battle-tested with built-in analytics, error handling, and support for 16+ networks in production.
Hook-based architecture allows you to control every approval and transaction, perfect for building custom user experiences.

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Supported Networks

The SDK supports 16+ blockchain networks across mainnet and testnet environments:

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Mainnets

  • Ethereum (ETH)
  • Base (ETH)
  • Arbitrum One (ETH)
  • Optimism (ETH)
  • Polygon (MATIC)
  • Avalanche (AVAX)
  • BNB Smart Chain (BNB)
  • Scroll (ETH)
  • Citrea Mainnet (cBTC)
  • Monad (MON)
  • Kaia Mainnet (KAIA)
  • Hyper EVM (HYPE)
  • MegaETH (ETH)

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Testnets

  • Sepolia (ETH)
  • Base Sepolia (ETH)
  • Arbitrum Sepolia (ETH)
  • Optimism Sepolia (ETH)
  • Polygon Amoy (MATIC)
  • Monad Testnet (MON)
  • Citrea Testnet (cBTC)
All testnets have complete feature parity with mainnet, allowing you to build and test without risk.

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Supported Tokens

The SDK supports the most widely-used tokens across all networks:
  • ETH - Ethereum (18 decimals)
  • USDC - USD Coin (6 decimals)
  • USDT - Tether USD (6 decimals)
  • USDM - USDm (18 decimals) - Available on MegaETH

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Prerequisites

Before getting started, ensure you have:
  • Node.js >= 18.0.0
  • npm >= 9.0.0 (or equivalent yarn/pnpm version)
  • An EIP-1193 compatible wallet provider (MetaMask, WalletConnect, etc.)

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What’s Next?

Install the SDK

Set up the Nexus SDK in your project

Quick Start Guide

Build your first cross-chain bridge transaction
Need Help? Join our Discord community or check out the GitHub repository for support and contributions.

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