n8n

Overview

n8n is an open-source workflow automation tool — self-hostable Zapier alternative. Visual editor with 400+ integrations, code nodes (JavaScript/Python), webhooks, cron triggers, and branching logic. Free when self-hosted.

Instructions

Step 1: Self-Host with Docker

# docker-compose.yml — n8n with PostgreSQL persistence
services:
  n8n:
    image: n8nio/n8n
    ports: ["5678:5678"]
    environment:
      N8N_BASIC_AUTH_ACTIVE: "true"
      N8N_BASIC_AUTH_USER: admin
      N8N_BASIC_AUTH_PASSWORD: changeme
      DB_TYPE: postgresdb
      DB_POSTGRESDB_HOST: postgres
      DB_POSTGRESDB_DATABASE: n8n
      DB_POSTGRESDB_USER: n8n
      DB_POSTGRESDB_PASSWORD: n8n
      WEBHOOK_URL: https://n8n.example.com/
    volumes: [n8n_data:/home/node/.n8n]
  postgres:
    image: postgres:16
    environment:
      POSTGRES_DB: n8n
      POSTGRES_USER: n8n
      POSTGRES_PASSWORD: n8n
    volumes: [pgdata:/var/lib/postgresql/data]
volumes:
  n8n_data:
  pgdata:

Step 2: Webhook Trigger

// n8n receives webhooks and processes them through visual workflows
// Example: Webhook → Slack notification → Google Sheet log

// Trigger URL: https://n8n.example.com/webhook/order-received
// POST body: { "order_id": "123", "customer": "john@example.com", "total": 99.99 }

Step 3: Code Node (JavaScript)

// Inside n8n Code node — transform data between steps
const items = $input.all()
return items.map(item => ({
  json: {
    fullName: `${item.json.firstName} ${item.json.lastName}`,
    email: item.json.email.toLowerCase(),
    isVIP: item.json.totalOrders > 10,
  }
}))

Step 4: API Workflow

Build workflows visually that:

1. Webhook receives order data
2. IF node checks if order > $100
3. Slack sends notification to #sales
4. Google Sheets logs the order
5. SendGrid sends confirmation email
6. HTTP Request updates CRM

Guidelines

• Self-hosted n8n is free and unlimited. Cloud starts at $20/month.
• 400+ built-in integrations (Slack, Gmail, Airtable, Stripe, Shopify, GitHub, etc.).
• Use Code nodes for complex logic — full JavaScript/Python support.
• Workflows can be triggered by webhooks, cron schedules, or other workflows.