Staff Software Engineer - Pos Integrations

ON; Greater London; On-site; GBP 110,000 - 170,000; Full time

Job summary

On seeks a Senior Lead - Staff Software Engineer to architect and scale our global retail technology infrastructure. You will bridge retail strategy and engineering, connecting POS, ERP, OMS and replenishment platforms with cloud-native, event-driven design and robust security.

You will drive technical standards, lead complex integrations across online and offline channels, and mentor a team of engineers to elevate reliability and delivery velocity.

Qualifications

• Proven track record designing, building and operating backend systems in production.
• Strong experience with POS, ERP integrations and replenishment/back-end retail software.
• Expertise in cloud-native, event-driven architectures and scalable integration pipelines.
• Ability to guide test automation, CI/CD and observability practices.

Responsibilities

• Lead architecture, design and scaling of backend systems and integration pipelines across POS, ERP, OMS and CRM.
• Drive operational excellence with observability, metrics and tracing; improve platform stability.
• Mentor engineers and shape a high-quality, collaborative engineering culture.
• Collaborate with Architecture, Product and Retail Ops to align solutions with strategy.

Skills

Node.js

TypeScript

Backend architecture

Event-driven

REST/GraphQL

Tools

Kafka

RabbitMQ

AWS

PostgreSQL

Terraform

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.

We're looking for a Senior Lead - Staff Software Engineer to architect and scale our core retail technology infrastructure - spanning Point of Sale (POS), ERP/financial system integrations, replenishment software, and omnichannel commercial capabilities like clienteling and digital queuing. You will bridge retail strategy and technology, designing resilient event-driven architectures, shaping complex integrations across online and offline channels, and eliminating domain bottlenecks to enable sustainable business growth. Joining the Retail team, you will collaborate closely with cross-functional partners in Architecture, Product, QA, and Retail Operations to elevate engineering standards and redefine physical retail at scale.

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.