Shopify Load & Scale

Overview

Load test Shopify app integrations while respecting API rate limits. Plan capacity for high-traffic events like Black Friday / Cyber Monday (BFCM).

Prerequisites

• k6 load testing tool installed (

  brew install k6

  )
• Test store with API access (never load test production)
• Understanding of Shopify rate limits per plan

Instructions

Step 1: Understand Capacity Constraints

Your app's throughput is bounded by Shopify's rate limits, not your infrastructure:

Plan	GraphQL Points	Restore Rate	Max Sustained QPS	Burst Capacity
Standard	1,000	50/sec	~10 queries/sec	1,000 points burst
Shopify Plus	2,000	100/sec	~20 queries/sec	2,000 points burst

A typical product query costs 10-50 points. At 50 points/query, Standard supports ~1 query/second sustained.

Step 2: k6 Load Test Script

k6 script with Shopify-specific custom metrics (throttle tracking, query cost trends, error rates) and automatic request pacing.

See k6 Load Test Script for the complete test script.

Step 3: Run Load Test

# Against a test store — NEVER production
k6 run \
  --env SHOPIFY_STORE=dev-store.myshopify.com \
  --env SHOPIFY_ACCESS_TOKEN=shpat_test_token \
  shopify-load-test.js

# Output results to InfluxDB for Grafana dashboards
k6 run --out influxdb=http://localhost:8086/k6 shopify-load-test.js

Step 4: BFCM / Flash Sale Preparation

Pre-BFCM preparation including cache pre-warming, Storefront API offloading, bulk inventory sync, and Kubernetes HPA configuration for webhook processing.

See BFCM Preparation for application-level and infrastructure scaling patterns.

Output

• Load test script calibrated to Shopify rate limits
• Performance baseline documented
• BFCM preparation checklist completed
• Infrastructure scaling configured for webhook volume

Error Handling

Issue	Cause	Solution
k6 shows high error rate	Hitting rate limits	Reduce VUs, increase sleep between requests
All requests THROTTLED	Exceeding 50 points/sec	Space queries further apart
Webhooks backing up	Slow processing	Respond 200 immediately, queue processing
Cache stampede on sale start	All caches expire at once	Stagger cache TTLs, pre-warm

Examples

Quick Capacity Estimate

# How many queries can you sustain?
# Standard plan: 50 points/sec restore
# Your query costs: check with debug header

curl -sf "https://$STORE/admin/api/${SHOPIFY_API_VERSION:-2025-04}/graphql.json" \
  -H "X-Shopify-Access-Token: $TOKEN" \
  -H "Content-Type: application/json" \
  -H "Shopify-GraphQL-Cost-Debug: 1" \
  -d '{"query": "{ products(first: 10) { edges { node { id title } } } }"}' \
  | jq '"Query cost: \(.extensions.cost.actualQueryCost) points. Max sustained: \(50 / .extensions.cost.actualQueryCost) queries/sec"'

Resources

• Shopify Rate Limits
• Shopify Plus Rate Limits
• k6 Documentation
• BFCM Preparation Guide