Instantly Performance Tuning

Overview

Optimize Instantly cold outreach campaigns for deliverability and API throughput. Focus on lead upload batching, campaign analytics caching, email warmup scheduling, and webhook processing for reply tracking.

Prerequisites

Instantly API key (v1 REST API)
Understanding of email sending limits and warmup
Redis or database for campaign state caching
Webhook endpoint for reply/bounce tracking

Instructions

Step 1: Batch Lead Upload with Rate Limiting

const INSTANTLY_API = 'https://api.instantly.ai/api/v1';

async function batchUploadLeads(
  campaignId: string,
  leads: Array<{ email: string; first_name?: string; company?: string }>,
  batchSize = 100
) {
  const results = { uploaded: 0, errors: 0 };

  for (let i = 0; i < leads.length; i += batchSize) {
    const batch = leads.slice(i, i + batchSize);

    const response = await fetch(`${INSTANTLY_API}/lead/add`, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({
        api_key: process.env.INSTANTLY_API_KEY,
        campaign_id: campaignId,
        skip_if_in_workspace: true,
        leads: batch,
      }),
    });

    if (response.ok) {
      results.uploaded += batch.length;
    } else {
      results.errors += batch.length;
    }

    // Respect rate limits: 10 req/sec
    await new Promise(r => setTimeout(r, 200));  # HTTP 200 OK
  }
  return results;
}

Step 2: Cache Campaign Analytics

import { LRUCache } from 'lru-cache';

const analyticsCache = new LRUCache<string, any>({
  max: 100,
  ttl: 1000 * 60 * 5, // 5 min - analytics change slowly  # 1000: 1 second in ms
});

async function getCampaignAnalytics(campaignId: string) {
  const cacheKey = `analytics:${campaignId}`;
  const cached = analyticsCache.get(cacheKey);
  if (cached) return cached;

  const response = await fetch(
    `${INSTANTLY_API}/analytics/campaign/summary?api_key=${process.env.INSTANTLY_API_KEY}&campaign_id=${campaignId}`
  );
  const data = await response.json();
  analyticsCache.set(cacheKey, data);
  return data;
}

async function getAllCampaignMetrics() {
  const campaigns = await fetch(
    `${INSTANTLY_API}/campaign/list?api_key=${process.env.INSTANTLY_API_KEY}`
  ).then(r => r.json());

  return Promise.all(
    campaigns.map((c: any) => getCampaignAnalytics(c.id))
  );
}

Step 3: Efficient Lead Status Polling

async function* paginateLeads(campaignId: string, limit = 100) {
  let skip = 0;
  let hasMore = true;

  while (hasMore) {
    const response = await fetch(`${INSTANTLY_API}/lead/get`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        api_key: process.env.INSTANTLY_API_KEY,
        campaign_id: campaignId,
        limit,
        skip,
      }),
    });

    const leads = await response.json();
    if (!leads.length) { hasMore = false; break; }

    yield* leads;
    skip += limit;
    await new Promise(r => setTimeout(r, 150));
  }
}

// Usage: stream leads without loading all into memory
for await (const lead of paginateLeads('campaign-123')) {
  if (lead.status === 'replied') {
    await processReply(lead);
  }
}

Step 4: Webhook Reply Processing Queue

const replyQueue: any[] = [];

async function handleInstantlyWebhook(event: any) {
  if (event.event_type === 'reply_received') {
    replyQueue.push({
      leadEmail: event.lead_email,
      campaignId: event.campaign_id,
      replyText: event.reply_text,
      timestamp: Date.now(),
    });
  }
  // Process asynchronously
  setImmediate(drainReplyQueue);
}

async function drainReplyQueue() {
  while (replyQueue.length > 0) {
    const reply = replyQueue.shift();
    // Invalidate analytics cache
    analyticsCache.delete(`analytics:${reply.campaignId}`);
    await syncReplyToCRM(reply);
  }
}

Error Handling

Issue	Cause	Solution
429 rate limit	Over 10 req/sec	Add 200ms delay between requests
Duplicate leads	Re-uploading same list	Use `skip_if_in_workspace: true`
Stale analytics	Cached too long	Reduce TTL or invalidate on webhook
Upload timeout	Batch too large	Reduce batch size to 100 leads

Examples

Campaign Health Monitor

async function monitorCampaigns() {
  const metrics = await getAllCampaignMetrics();
  return metrics.map((m: any) => ({
    campaign: m.campaign_name,
    sent: m.sent,
    opened: m.opened,
    replied: m.replied,
    openRate: ((m.opened / m.sent) * 100).toFixed(1) + '%',
    replyRate: ((m.replied / m.sent) * 100).toFixed(1) + '%',
  }));
}

Resources

Output

Configuration files or code changes applied to the project
Validation report confirming correct implementation
Summary of changes made and their rationale

instantly-performance-tuning