Senior Backend Engineer - Commercial Technology

Worky; Greater London; On-site; GBP 90,000 - 130,000; Full time

Job summary

On seeks a Senior Backend Engineer to design, build, deploy, test and operate our digital services. Based in London, you will collaborate with cross-functional teams to scale our online business, including e-commerce platforms and partner portals.

You will own core backend components, ensure performance and reliability, and contribute to a dynamic, growth-focused environment. You will work with NestJS, TypeScript, GraphQL, PostgreSQL, and cloud-native tools in a RESTful/GraphQL stack, promoting

Qualifications

• Strong backend development background with shipping high-quality software.
• Proficiency in Node.js and TypeScript, with deep understanding of modern backend frameworks.
• Hands-on experience with NestJS and GraphQL APIs.
• Solid experience with PostgreSQL and data modeling.
• Experience with cloud platforms (GCP) and containerization (Docker, Kubernetes).
• Familiarity with microservices architecture and scalable systems.
• Collaborative, agile team player with good communication skills.

Responsibilities

• Design, develop, and maintain robust backend services using NestJS, TypeScript, GraphQL.
• Own key components within the Commercial cluster to serve web, mobile, and partner integrations.
• Collaborate with frontend, product, and other stakeholders to deliver end-to-end features.
• Apply agentic engineering practices and leverage AI in daily workflows.
• Deploy and operate services in a cloud-native GCP environment with Kubernetes and Docker.
• Contribute to resilient distributed systems capable of handling growth.

Skills

Node.js

TypeScript

NestJS

GraphQL

PostgreSQL

GCP

Docker

Kubernetes

Microservices

Agile methodologies

Tools

MikroORM

Kafka

Job description

In Short:

Our Direct to Consumer business is performing and growing strongly, which is why we - within the Commercial Platform team at On - are looking for a Senior Backend Engineer to scale On’s online business to the next level. As an experienced engineer, you will be responsible to design, build, deploy, test and operate our digital services. You will be sitting in our office in London and collaborating closely with the cross-functional Digital teams across our key locations.

The Senior Software Engineer role will report to the relevant Senior Lead - Engineering Manager within Commercial Technology.

Your Mission

As a Senior Backend Engineer in our Commercial cluster, you will be at the heart of On's digital ecosystem. You will design, build, and scale the critical services that power our global e-commerce platform, B2B partner portals, and retail experiences. Your work will directly impact how we deliver product information, checkout process and end-to-end e-com user experience, to our customers and partners, ensuring a seamless and premium experience that drives our commercial success.

What You'll Do

• Design, develop, and maintain robust and scalable backend services using our modern tech stack, with a primary focus on NestJS, TypeScript, and GraphQL.


• Take ownership of key components within our Commercial cluster, ensuring they are performant, reliable, and meet the needs of various client applications (web, mobile, and third-party integrations).


• Collaborate closely with frontend engineers, product managers, and other stakeholders to deliver end-to-end features.


• Agentic engineering, comfortable using AI in your daily workflow.


• Deploy and operate your services in a cloud-native environment on Google Cloud Platform (GCP), using Kubernetes and Docker.


• Engage with and contribute to our distributed systems landscape, helping to build resilient systems that can handle our growing scale.

Your Story

• A strong background in backend development, with proven experience building and shipping high-quality software.


• Proficiency in Node.js and TypeScript, with a deep understanding of modern backend frameworks. Hands-on experience with NestJS is a significant advantage.


• Solid experience in designing, building, and consuming GraphQL APIs.


• Strong knowledge of relational databases (e.g., PostgreSQL) and data modeling.


• Hands-on experience with cloud platforms (GCP is a plus) and containerization technologies (Docker, Kubernetes).


• You are a collaborative team player with excellent communication skills, comfortable working in an agile environment.

Bonus points for experience with:

• ORM tools like MikroORM


• Event-driven systems (e.g., Kafka, BullMQ, Pub/Sub)


• E-com ecosystems

Your Team:

As you might expect from a running brand, the wider E-Commerce team at On is a fast-paced place to be. You will work in the diverse Commercial Technology domain, collaborating with Software Engineers, QA Engineers, Product Managers, Data Analytics, Marketing and others of stream-aligned or platform teams that are located in Berlin, Zurich and London.

What We Offer

At On, we are a team of explorers, dreamers, and innovators. We live and breathe our mission to ignite the human spirit through movement. We offer a dynamic, fast-paced, and collaborative environment where you can make a real impact. You'll be surrounded by passionate and talented colleagues, with plenty of opportunities for professional growth and development.

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.