Build on Sei
@sei-js is the complete TypeScript SDK for building applications on Sei Network. Whether you’re creating DeFi protocols, NFT marketplaces, or blockchain games, @sei-js provides everything you need to ship faster. Works with your favorite tools: Sei is fully EVM-compatible, so you can use Viem, Ethers.js, Foundry, Hardhat, and all your existing Ethereum development tools without any changes. @sei-js extends these tools with Sei-specific features like precompiled contracts and optimized wallet connections.Quick Start
Build your first Sei app in under 10 minutes
Contributing
Help improve @sei-js and contribute to the project
Why @sei-js?
Complete TypeScript support
Complete TypeScript support
Full type safety for every function, contract interaction, and API response. Catch errors at compile time.
Production ready
Production ready
Battle-tested components used by major applications in the Sei ecosystem.
Optimized for Sei
Optimized for Sei
Take advantage of Sei’s fast finality, low gas fees, and native order matching.
Package ecosystem
@sei-js/precompiles
Native blockchain function accessAccess Sei’s precompiled contracts directly from your EVM applications.
@sei-js/create-sei
Project scaffolding and templatesBootstrap new Sei projects with pre-configured templates and tooling.
@sei-js/sei-global-wallet
Universal wallet connectionsConnect to any Sei-compatible wallet using the EIP-6963 standard.
@sei-js/ledger
Hardware wallet integrationSecure transaction signing with Ledger hardware wallets.
@sei-js/mcp-server
LLM blockchain integrationTeach Claude, ChatGPT, or any LLM to interact with the Sei blockchain.
🤖 Teach Your LLM About SeiConnect Claude, ChatGPT, or any LLM to the Sei blockchain with @sei-js/mcp-server. Your AI assistant can check balances, transfer tokens, deploy contracts, and guide users through the entire @sei-js ecosystem.Get Started with MCP →
Community & Support
- GitHub Discussions - Ask questions and discuss features
- Discord - Join the Sei developer community
- Official Documentation - Complete Sei protocol documentation
Report Issues
- GitHub Issues - Report bugs and request features
- Include reproduction steps and environment details
- Check existing issues before creating new ones