customerio-reliability-patterns

name	customerio-reliability-patterns
description	Implement Customer.io reliability and fault-tolerance patterns. Use when building circuit breakers, fallback queues, idempotency, or graceful degradation for Customer.io integrations. Trigger: "customer.io reliability", "customer.io resilience", "customer.io circuit breaker", "customer.io fault tolerance".
allowed-tools	Read, Write, Edit, Bash(npm:*), Bash(npx:*), Glob, Grep
version	1.14.0
license	MIT
author	Jeremy Longshore <[e-mail]>
tags	["saas","customer-io","reliability","circuit-breaker","resilience"]
compatibility	Designed for Claude Code

Customer.io Reliability Patterns

Overview

Implement fault-tolerant Customer.io integrations: circuit breaker (stop cascading failures), retry with jitter (handle transient errors), fallback queue (survive outages), idempotency guard (prevent duplicates), and graceful degradation (never crash your app for analytics).

Prerequisites

• Working Customer.io integration
• Understanding of failure modes (429, 5xx, timeouts, DNS failures)
• Redis (recommended for queue-based patterns)

Instructions

Pattern 1: Circuit Breaker

// lib/circuit-breaker.ts
type CircuitState = "CLOSED" | "OPEN" | "HALF_OPEN";

export class CircuitBreaker {
  private state: CircuitState = "CLOSED";
  private failureCount = 0;
  private successCount = 0;
  private lastFailureTime = 0;

  constructor(
    private readonly failureThreshold: number = 5,
    private readonly successThreshold: number = 3,
    private readonly resetTimeoutMs: number = 30000
  ) {}

  get currentState(): CircuitState {
    if (this. === ) {
      
       (.() - . > .) {
        . = ;
        . = ;
      }
    }
     .;
  }

   execute<T>(:  <T>): <T> {
     (. === ) {
        ();
    }

     {
       result =  ();
      .();
       result;
    }  (err) {
      .();
       err;
    }
  }

   ():  {
    . = ;
     (. === ) {
      .++;
       (. >= .) {
        . = ;
        .();
      }
    }
  }

   ():  {
    .++;
    . = .();
     (. >= .) {
      . = ;
      .(
         +
        
      );
    }
  }

  (): { : ; : ; :  |  } {
     {
      : .,
      : .,
      : . ?  (.) : ,
    };
  }
}