Customer.io Security Basics

Overview

Implement security best practices for Customer.io integrations including credential management, PII handling, webhook verification, and GDPR compliance.

Prerequisites

• Customer.io account with admin access

• Understanding of your data classification

• Environment variable management

Instructions

Step 1: Set Up Secure Credential Management

Use a secrets manager (GCP Secret Manager, AWS Secrets Manager) instead of environment variables for production credentials.

Step 2: Implement PII Data Handling

Hash sensitive identifiers with SHA-256 before sending. Sanitize user attributes to remove highly sensitive fields (SSN, credit card) and optionally hash PII fields (phone, address).

Step 3: Configure API Key Rotation

Establish a 90-day rotation schedule. Automate through secrets manager where possible with zero-downtime rotation procedures.

Step 4: Secure Webhook Endpoints

Verify Customer.io webhook signatures using HMAC-SHA256 with crypto.timingSafeEqual . Create Express middleware for automatic verification.

Step 5: Implement Access Controls

Define role-based permissions (admin, editor, viewer) and enable audit logging for security-sensitive operations.

Step 6: Handle Data Retention

Implement user suppression and deletion for GDPR/CCPA compliance. Create anonymization functions for historical analytics data.

For detailed implementation code and configurations, load the reference guide: Read(${CLAUDE_SKILL_DIR}/references/implementation-guide.md)

Security Checklist

• API keys stored in secrets manager

• API keys rotated every 90 days

• Webhook signatures verified

• PII sanitized before sending

• Minimum necessary data sent

• Team access follows least-privilege

• Audit logging enabled

• GDPR/CCPA deletion process documented

• SSL/TLS enforced for all API calls

Error Handling

Issue Solution

Exposed credentials Rotate immediately, audit access

PII leak Delete from Customer.io, notify DPO

Unauthorized access Review access logs, revoke access

Resources

• Customer.io Security

• GDPR Compliance

• Suppression API

Next Steps

After implementing security, proceed to customerio-prod-checklist for production readiness.

Output

• Configuration files or code changes applied to the project

• Validation report confirming correct implementation

• Summary of changes made and their rationale

See security implementation details for output format specifications.

Examples

Basic usage: Apply customerio security basics to a standard project setup with default configuration options.

Advanced scenario: Customize customerio security basics for production environments with multiple constraints and team-specific requirements.