Senior Shopify / E-commerce Integration Engineer

You will own the integrations between commerce platforms (Shopify, POS, OMS, third-party SaaS) and the data that moves through them for a large replatforming program. The standard is data correctness at the systems-of-record level: orders, inventory and fulfillment must agree across every platform, provably, before and after cutover. This is a long-term, full-time engagement. It is backend integration engineering, not storefront or theme work.

Key Responsibilities:

Build and maintain REST and GraphQL integrations with Shopify, POS, OMS and third-party business applications

Implement OAuth flows, webhook verification and processing, retries, deduplication and error handling for production data flows

Handle the realities of distributed data: duplicate events, out-of-order delivery, partial failures, eventual consistency

Develop new API integrations with enterprise and SaaS platforms as the program expands

Own SQL and BigQuery work wherever integrations require data movement or transformation

Build automated reconciliation checks so systems of record stay in agreement

Troubleshoot production integrations and data quality issues end to end

Requirements:

5+ years of backend engineering focused on API integrations between enterprise or SaaS platforms

Strong Python in production

REST and GraphQL integration experience on both consuming and building sides

OAuth, API authentication, webhooks and robust error handling patterns

Practical command of idempotency, deduplication and reconciliation design

Strong SQL; hands-on data integration or ETL experience

AWS deployment experience with Docker and CI/CD

Fluent English

Minimum 4 hours daily overlap with US Eastern time, full-time availability

Nice to Have:

Google BigQuery

Shopify APIs (Admin GraphQL, webhooks, Fulfillment Orders) or Salesforce Commerce Cloud

POS, OMS, ERP or fulfillment system integration experience

Event-driven integration patterns: queues, event buses, connectors