On Staff Software Engineer - POS Integrations

On; City Of London; On-site; GBP 120,000 - 180,000; Full time

Job summary

On is seeking a senior engineering leader to drive architecture and systems integration across global retail platforms, connecting POS, ERP, OMS, CRM, and replenishment across formats. You will build cloud-native, event-driven architectures with Kafka/RabbitMQ, REST/GraphQL APIs, and focus on security, reliability, and real-time data synchronization.

Collaborate with architecture leadership, product, and retail operations to scale, mentor engineers, and balance standardization with local market

Qualifications

• Proven experience designing, building, and operating POS systems in a production retail environment.
• Hands-on experience with ERP integrations and retail backend software (replenishment, inventory management, OMS).
• Strong retail operations knowledge with an understanding of physical store layouts and multi-format rollouts.

Responsibilities

• Lead architecture, design, and scaling of backend systems and integration pipelines across POS, ERP, OMS, CRM, and replenishment.
• Build cloud-native, event-driven architectures with Kafka/RabbitMQ and REST/GraphQL APIs for real-time data sync.
• Architect secure, high-availability omnichannel services with OAuth2/SSO and data integrity across online/offline retail.
• Drive observability and ops excellence with metrics, tracing, and alerting (e.g., New Relic) for POS/retail infra.
• Lead cross-system incident resolution and harden platform stability and performance.
• Guide CI/CD, contract testing, load testing, and test automation to ensure reliable releases.
• Mentor engineers and promote technical rigor; collaborate with leadership to align with business strategy.
• Drive innovation by rolling out clienteling, digital queuing, and connected in-store experiences.
• Balance global standardization with local market variations across geographies.
• Partner with Architecture, Product, and Retail Ops to shape long-term strategy at On.

Job description

In Short:

As we rapidly expand our global retail footprint across multiple store formats and geographies, we are laying the foundation for a scalable, future-ready retail technology ecosystem. To support this rapid growth, we need a senior engineering leader to act as a core pillar of domain knowledge, driving both operational excellence and technology innovation across our retail systems.

Your Mission:

Retail Platform Architecture & Systems Integration:

• Lead the architecture, design, and scaling of backend systems and integration pipelines connecting POS, ERP (financial systems), OMS, CRM, and replenishment platforms across global physical store formats.
• Build cloud-native, event-driven architectures utilizing message brokers (Kafka, RabbitMQ) and resilient REST/GraphQL APIs for real-time and batch data synchronization.
• Architect secure, high-availability omnichannel services, ensuring robust authentication (OAuth2, SSO) and data integrity across online and offline retail operations.

Operational Excellence & Technical Leadership:

• Drive operational excellence across POS and standard retail infrastructure, establishing observability best practices (metrics, distributed tracing, alerting via tools like New Relic).
• Lead root-cause investigation and resolution of complex, cross-system issues, continuously hardening platform stability and system performance.
• Establish rigorous engineering and quality standards, guiding test automation strategies (contract testing, load testing, CI/CD pipelines) to ensure reliable release velocity.

Domain Ownership & Innovation:

• Act as a key domain expert for retail operations technology, distributing technical knowledge across engineering teams to build a resilient, multi-pillar domain structure.
• Drive commercial innovation by architecting and rolling out next-generation retail capabilities, including clienteling, digital queuing, and connected in-store digital experiences.
• Balance global system standardization with local market and physical store format variations across international geographies.

Strategic Collaboration & Mentorship:

• Partner with architecture leadership (Staff Principals), Product Managers, and Retail Operations to align technical solutions with long-term business strategy and roadmap decisions.
• Guide technical decision-making, evaluate vendor platforms, and influence the broader composable commerce strategy at On.
• Mentor and guide software engineers, fostering a culture of technical rigor, continuous learning, and collaborative problem-solving.

Your Story:

Deep Domain Expertise:

• Proven experience designing, building, and operating Point of Sale (POS) systems in a production retail environment.
• Hands-on experience with financial system integrations (ERP) and retail backend software (e.g., replenishment, inventory management, OMS).
• Strong retail operations knowledge with an understanding of physical store layouts, multi-format rollouts, and physicalization challenges.

Technical Proficiency:

• Extensive experience in backend engineering using modern technologies (Node.js, TypeScript, or equivalent execution environments).
• Demonstrated expertise in event-driven architecture, asynchronous message brokers (e.g., Kafka), and cloud-native microservices (AWS, GCP, or Azure).
• Solid grasp of relational databases (e.g., PostgreSQL), API design (REST, GraphQL), and Infrastructure-as-Code (Terraform).

Leadership & Execution:

• Track record of leading solution design for complex, large-scale systems and driving end-to-end delivery of major platforms.
• Experience operating in global or multi-geography retail environments, balancing standardization with local market requirements.
• Ability to balance rapid commercial innovation with high system reliability, security, and operational stability.

Your Team:

As part of our Retail team, you’ll sit alongside backend engineers, QA, and retail operations specialists to power the future of physical and omnichannel retail technology. Working under retail technology leadership and partnering directly with architecture and product leaders, your work will connect online and offline worlds, power global expansion, and support a mission that’s bigger than any one screen: to ignite the human spirit through movement.

On is an Equal Opportunity Employer. We are committed to creating a work environment that is fair and inclusive, where all decisions related to recruitment, advancement, and retention are free of discrimination.