npm install @stateset/sdk

import { StateSet } from '@stateset/sdk';

// Initialize client
const stateset = new StateSet({
  apiKey: process.env.STATESET_API_KEY,
  network: 'mainnet', // 'mainnet' | 'testnet'
  options: {
    timeout: 30000, // 30 seconds
    retries: 3,
    webhookSecret: process.env.WEBHOOK_SECRET
  }
});

import { verifyWebhookSignature } from '@stateset/sdk';

app.post('/webhooks/stateset', express.raw({type: 'application/json'}), (req, res) => {
  const sig = req.headers['x-stateset-signature'];
  
  try {
    const event = verifyWebhookSignature(
      req.body,
      sig,
      process.env.WEBHOOK_SECRET
    );
    
    // Handle event
    switch(event.type) {
      case 'payment.succeeded':
        handlePaymentSuccess(event.data);
        break;
      // ... other events
    }
    
    res.status(200).send('OK');
  } catch (err) {
    res.status(400).send('Webhook Error');
  }
});

import { StateSetError } from '@stateset/sdk';

try {
  const payment = await stateset.payments.create({...});
} catch (error) {
  if (error instanceof StateSetError) {
    switch(error.type) {
      case 'invalid_request_error':
        console.error('Invalid parameters:', error.param);
        break;
      case 'authentication_error':
        console.error('Check your API key');
        break;
      case 'rate_limit_error':
        await sleep(error.retryAfter);
        // Retry request
        break;
    }
  }
}

pip install stateset

from stateset import StateSet
import os

# Initialize client
stateset = StateSet(
    api_key=os.getenv('STATESET_API_KEY'),
    network='mainnet',  # 'mainnet' or 'testnet'
    timeout=30,
    max_retries=3
)

from typing import List, Optional
from stateset.types import Payment, Order, Transfer

def process_payments(payments: List[Payment]) -> None:
    """Process a list of payments with full type safety."""
    for payment in payments:
        if payment.status == 'succeeded':
            send_receipt(payment.recipient, payment.amount)

def create_order(
    items: List[dict],
    customer_id: str,
    shipping_method: Optional[str] = 'standard'
) -> Order:
    """Create an order with type-checked parameters."""
    return stateset.orders.create(
        items=items,
        customer=customer_id,
        shipping={'method': shipping_method}
    )

go get github.com/stateset/stateset-go

package main

import (
    "github.com/stateset/stateset-go"
    "github.com/stateset/stateset-go/payment"
)

func main() {
    // Initialize client
    client := stateset.NewClient(
        os.Getenv("STATESET_API_KEY"),
        stateset.WithNetwork("mainnet"),
        stateset.WithTimeout(30 * time.Second),
        stateset.WithRetries(3),
    )
}

// Create payment
payment, err := client.Payments.Create(&payment.CreateParams{
    Amount:    stateset.Float64(100.00),
    Currency:  stateset.String("ssusd"),
    Recipient: stateset.String("stateset1abc..."),
})
if err != nil {
    // Handle error
    if statesetErr, ok := err.(*stateset.Error); ok {
        log.Printf("StateSet error: %s (code: %s)", 
            statesetErr.Message, statesetErr.Code)
    }
}

// Concurrent operations with goroutines
var wg sync.WaitGroup
payments := make([]*payment.Payment, 10)

for i := 0; i < 10; i++ {
    wg.Add(1)
    go func(index int) {
        defer wg.Done()
        p, _ := client.Payments.Create(&payment.CreateParams{
            Amount: stateset.Float64(100.00),
        })
        payments[index] = p
    }(i)
}

wg.Wait()

// pages/api/create-payment.ts
import { StateSet } from '@stateset/sdk';
import type { NextApiRequest, NextApiResponse } from 'next';

const stateset = new StateSet({
  apiKey: process.env.STATESET_SECRET_KEY
});

export default async function handler(
  req: NextApiRequest,
  res: NextApiResponse
) {
  try {
    const payment = await stateset.payments.create({
      amount: req.body.amount,
      currency: 'ssusd'
    });
    
    res.status(200).json(payment);
  } catch (error) {
    res.status(400).json({ error: error.message });
  }
}

# views.py
from django.http import JsonResponse
from django.views.decorators.csrf import csrf_exempt
from stateset import StateSet
import json

stateset = StateSet(api_key=settings.STATESET_API_KEY)

@csrf_exempt
def create_payment(request):
    if request.method == 'POST':
        data = json.loads(request.body)
        
        try:
            payment = stateset.payments.create(
                amount=data['amount'],
                currency='ssusd',
                recipient=data['recipient']
            )
            return JsonResponse(payment.to_dict())
        except Exception as e:
            return JsonResponse({'error': str(e)}, status=400)

const express = require('express');
const { StateSet } = require('@stateset/sdk');

const app = express();
const stateset = new StateSet({
  apiKey: process.env.STATESET_API_KEY
});

app.post('/api/payments', async (req, res) => {
  try {
    const payment = await stateset.payments.create({
      amount: req.body.amount,
      currency: 'ssusd'
    });
    
    res.json(payment);
  } catch (error) {
    res.status(400).json({ error: error.message });
  }
});

import { StateSet, MockStateSet } from '@stateset/sdk';

// Use mock client in tests
const stateset = process.env.NODE_ENV === 'test' 
  ? new MockStateSet()
  : new StateSet({ apiKey: process.env.STATESET_API_KEY });

// Mock client returns predictable responses
const payment = await stateset.payments.create({
  amount: 100.00,
  currency: 'ssusd'
});

console.log(payment.id); // 'pay_test_123'

import { createTestPayment, createTestOrder } from '@stateset/sdk/test';

describe('Payment Processing', () => {
  it('should process payment successfully', async () => {
    // Create test data
    const payment = createTestPayment({
      amount: 100.00,
      status: 'succeeded'
    });
    
    // Test your logic
    const result = await processPayment(payment);
    expect(result.success).toBe(true);
  });
});