Customer.io Reliability Patterns

Overview

Implement reliability patterns for fault-tolerant Customer.io integrations including circuit breakers, retries with jitter, fallback queues, and idempotency.

Prerequisites

• Customer.io integration working

• Understanding of failure modes

• Queue infrastructure (optional)

Instructions

Step 1: Implement Circuit Breaker

Build a circuit breaker with CLOSED/OPEN/HALF_OPEN states, configurable failure/success thresholds, and automatic recovery timeout.

Step 2: Add Retry with Jitter

Create exponential backoff with configurable jitter (0-30%) to prevent thundering herd. Skip retries on client errors (4xx except 429).

Step 3: Set Up Fallback Queue

Use BullMQ to queue operations when the circuit breaker is open, with exponential backoff retries starting at 1 minute.

Step 4: Build Graceful Degradation Layer

Wrap the Customer.io client with circuit breaker and fallback queue integration for automatic failover.

Step 5: Add Health Checks

Create a health check endpoint that tests API connectivity, reports circuit state, queue depth, and last success/failure times.

Step 6: Implement Idempotency

Use SHA-256 content hashing with LRU cache to prevent duplicate operations within a configurable window.

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

Error Handling

Pattern When to Use

Circuit Breaker Prevent cascade failures

Retry Transient errors (5xx, 429)

Fallback Queue Extended outages

Idempotency Duplicate prevention

Reliability Checklist

• Circuit breaker implemented

• Retry with exponential backoff

• Fallback queue for failures

• Health check endpoint

• Idempotency for duplicates

• Timeout configuration

• Graceful shutdown handling

Resources

• Circuit Breaker Pattern

• Retry Best Practices

Next Steps

After reliability patterns, proceed to customerio-load-scale for scaling.

Output

• Configuration files or code changes applied to the project

• Validation report confirming correct implementation

• Summary of changes made and their rationale

See Customerio Reliability Patterns implementation details for output format specifications.

Examples

Basic usage: Apply customerio reliability patterns to a standard project setup with default configuration options.

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