Solution / Application Architect - OMS Migration

We’re looking for a hands-on Solution/Application Architect to lead the design and modernization of a middleware component within an Order Management System (OMS) for a large retail client based in Markham, Ontario.

The organization is transitioning away from a third-party SaaS OMS platform and bringing the middleware solution back in-house. You’ll be responsible for shaping the architecture, integration strategy, and event-driven design as the company moves from a legacy monolithic setup to a modern, scalable cloud-native solution.

 

What You’ll Do:

• Lead the overall architecture and integration design for the new OMS middleware.

• Design and document solution diagrams, APIs, message flows, and integration touchpoints.

• Collaborate closely with teams across AS400, Zendesk, payment gateways, e-commerce, and data warehouse systems.

• Implement and guide event-driven, microservices-based patterns using Azure technologies (Event Hub, Kafka, or MQ).

• Work with a small middleware development team to deliver scalable, high-performing solutions.

• Identify and manage risks around third-party or “black box” vendor systems.

• Participate in knowledge transfer, discovery sessions, and solution validation with the OMS Manager.

Technical Environment:

• Cloud: Azure (AKS, containers, cloud-native services)

• Architecture: Event-driven, microservices, API-first (REST/gRPC/GraphQL)

• Messaging: Kafka, MQ, or Event Hub

• Data: SQL Server and Cosmos Database (NoSQL)

• Integrations: AS400 (legacy OMS), Zendesk, payment gateways, e-commerce platforms, data warehouse

• Performance & Security: Redis/Memcached caching, API gateways, OAuth2/JWT authentication

Must-Haves:

• Proven experience as an Application or Integration Architect in retail, commerce, or OMS environments

• 5+ years in microservices-based architecture, including 1-2 years in event-driven systems (Kafka/Event Hub)

• Strong experience with Azure, AKS, and containerized deployments

• Hands-on experience designing and integrating APIs with proper versioning and security

• Solid development foundation in Java or .NET

• Familiarity with payment gateway integrations (refunds, charges, reconciliation)

• Comfortable working with legacy systems (AS400) and limited-visibility vendor products

• Excellent communication skills — able to explain technical designs to both business and technical stakeholders

• Comfortable attending on-site whiteboard sessions and presenting architectural solutions

Thanks,