Selendra SDK

TypeScript library for building dApps on Selendra. Wraps Substrate pallets with React hooks.

Status

Install

npm install @selendrajs/sdk

Package: @selendrajs/sdk

When to Use

Use SDK if:

• Building React dApps
• Need Substrate features (staking, governance)
• Want unified accounts

Use polkadot.js if:

• Need full Substrate control
• Non-React apps

Use web3.js/ethers if:

• Pure EVM dApp only

Quick Example

import { SelendraSDK } from "@selendrajs/sdk";

const sdk = new SelendraSDK({
  endpoint: "wss://rpc-testnet.selendra.org",
});
await sdk.connect();

const balance = await sdk.getBalance(address);

Features

TypeScript - Core SDK API

React - Hooks and components

Rust - Rust SDK (in development)

Status - Feature completion

Use Cases - Real examples

• getCandidates() - Get candidates
• vote() - Vote for council
• submitCandidacy() - Run for council

Account Management:

• get_balance() - Query account balance
• get_account_info() - Full account data (nonce, balances)
• transfer() - Send tokens
• account_id() - Get account ID

Unified Accounts:

• substrateToEvm() - Convert addresses
• evmToSubstrate() - Convert addresses
• claimDefaultEvmAddress() - Claim EVM address
• hasMappingOnChain() - Check mapping exists

React Hooks (Production)

import { useSelendra, useStaking, useBalance } from "@selendrajs/sdk/react";

function MyComponent() {
  const { isConnected } = useSelendra();
  const { balance } = useBalance(address);
  const { bond, nominate } = useStaking();

  return <div>Balance: {balance}</div>;
}

Available hooks: 15 production-ready hooks

• Connection management
• Balance queries
• Transaction handling
• Contract interaction
• Event listening
• Block subscriptions
• Staking operations
• Network status

EVM (Beta - Limited)

Works:

• getBalance() - Query ETH balance
• getBlockNumber() - Current block
• getTransactionCount() - Get nonce

Not Ready:

• Contract deployment
• Gas estimation
• Transaction history
• Cross-chain bridge

For full EVM support, use web3.js or ethers.js directly.

Documentation

• TypeScript API Reference - Complete API docs
• React Hooks Guide - React integration
• Rust API - Rust SDK (in development)
• Production Status - What works, what doesn't
• Use Cases - When to use SDK
• Migration Guides - From polkadot.js or ethers

Network Endpoints

Mainnet:

• WebSocket: wss://rpc.selendra.org
• HTTP: https://rpc.selendra.org

Testnet:

• WebSocket: wss://rpc-testnet.selendra.org

Examples

// Staking example
import { Connection, keypair_from_string } from "@selendrajs/sdk";

const conn = await Connection.new("wss://rpc-testnet.selendra.org");
const keypair = keypair_from_string("//Alice");
const signed = conn.sign(keypair);

// Bond tokens
const tx = await signed.stake_bond(1_000_000_000_000);

// Nominate validators
const validators = [validator1, validator2];
await signed.stake_nominate(validators);

// React example
import { SelendraProvider } from "@selendrajs/sdk/react";

function App() {
  return (
    <SelendraProvider endpoint="wss://rpc.selendra.org">
      <Dashboard />
    </SelendraProvider>
  );
}

Package Info

npm: @selendrajs/sdk
Status: Published and available on npm registry
TypeScript: Full type support
React: ≥18.0.0
Bundle: Tree-shakeable ESM + CJS

Support

• GitHub Issues: github.com/selendra/selendra-sdk/issues
• GitHub Discussions: github.com/selendra/selendra-sdk/discussions
• Documentation: selendra.org/docs/sdk

Comparison: SDK vs Direct Libraries

Built on top of these established libraries:

Selendra SDK wraps Polkadot.js for Substrate and Ethers.js for EVM. Choose the tool that fits your use case.