customerio-performance-tuning

# Customer.io Performance Tuning

## Overview
Optimize Customer.io API performance for high-volume and low-latency integrations.

## Prerequisites
- Customer.io integration working
- Monitoring infrastructure
- Understanding of your traffic patterns

## Instructions

### Step 1: Connection Pooling
```typescript
// lib/customerio-pooled.ts
import { TrackClient, RegionUS } from '@customerio/track';
import { Agent } from 'http';
import { Agent as HttpsAgent } from 'https';

// Create connection pool with keep-alive
const httpsAgent = new HttpsAgent({
  keepAlive: true,
  keepAliveMsecs: 30000,
  maxSockets: 100,
  maxFreeSockets: 20,
  timeout: 30000
});

// Create client with connection pooling
export function createPooledClient(): TrackClient {
  return new TrackClient(
    process.env.CUSTOMERIO_SITE_ID!,
    process.env.CUSTOMERIO_API_KEY!,
    {
      region: RegionUS,
      // Pass custom agent for connection pooling
      httpAgent: httpsAgent
    }
  );
}

// Singleton for connection reuse
let clientInstance: TrackClient | null = null;

export function getClient(): TrackClient {
  if (!clientInstance) {
    clientInstance = createPooledClient();
  }
  return clientInstance;
}
```

### Step 2: Batch Processing
```typescript
// lib/batch-processor.ts
import { TrackClient } from '@customerio/track';

interface BatchItem {
  type: 'identify' | 'track';
  userId: string;
  data: Record<string, any>;
}

export class BatchProcessor {
  private batch: BatchItem[] = [];
  private batchSize: number;
  private flushInterval: number;
  private timer: NodeJS.Timer | null = null;

  constructor(
    private client: TrackClient,
    options: { batchSize?: number; flushIntervalMs?: number } = {}
  ) {
    this.batchSize = options.batchSize || 100;
    this.flushInterval = options.flushIntervalMs || 1000;
    this.startFlushTimer();
  }

  add(item: BatchItem): void {
    this.batch.push(item);

    if (this.batch.length >= this.batchSize) {
      this.flush();
    }
  }

  asy