Lead Software Engineer - Finance Technology

Location: London

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Technology

In short

As a Senior Engineer in the Finance cluster, you will architect and build the technological infrastructure that powers On’s global financial operations. You will play a pivotal role in transitioning our finance ecosystem toward a "North Star" architecture - moving away from legacy patterns toward a high-performance, event-driven landscape. At On, we believe everyone in the world should have access to the best sportswear. For this to happen, we need high-performing, robust financial solutions that ensure our global growth is supported by accurate data, compliant processes, and efficient automation across all legal entities. By leveraging Kafka for real-time data streaming and NestJS for robust microservices, you will ensure our financial systems - from global tax compliance to automated bank integrations - are scalable, reliable, and future-proof.

Your Mission

Architect for the North Star: Write well-tested, scalable code to migrate legacy tools to modern NestJS services.
Event-Driven Finance: Build and operate streaming pipelines using Kafka to ensure financial data is consistent and available to other technology domains.
ERP Integration: Deeply integrate D365 F&O with cloud-native applications to automate complex workflows.
Operational Excellence: Drive the adoption of CI/CD best practices, specifically improving how we deploy and manage cloud resources via GitHub.
Engineering Leadership: Partner with the Head of Engineering to split complex projects into small, logical units of work (User Stories and Subtasks) to maintain high velocity.

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Your story

TypeScript Mastery: Extensive experience building backend services specifically with NestJS and Node.js.
Streaming Expertise: Proven experience implementing Apache Kafka in production environments to handle high-throughput data.
Logical Problem Solver: Proficient in leading technical discovery and breaking down "Big Bang" migrations into manageable, iterative releases.
Cloud & DevOps Native: Strong track record with Kubernetes, Terraform, and automating deployments through GitHub Actions.
Domain Curiosity: Technical experience with ERP systems (D365 F&O) and financial processes - such as Landed Cost, tax engines, or CNAB bank integrations - is a plus.
Collaborative Partner: You communicate effectively with both technical peers and Finance stakeholders to translate business needs into architectural requirements.

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About the Team

The Finance Engineering team is at the heart of On's global expansion. We are responsible for the "financial engine," ensuring that as On scales, our systems remain compliant, automated, and transparent. We value collaboration, creating an environment where open communication and diverse perspectives are a catalyst for innovation. We challenge and inspire one another to turn great ideas into reality.

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What we offer

On is a place that is centered around growth and progress. We offer an environment designed to give people the tools to develop holistically – to stay active, to learn, explore and innovate. Our distinctive approach combines a supportive, team-oriented atmosphere, with access to personal self-care for both physical and mental well-being, so each person is led by purpose.

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.

Build the better you

What to expect

We want to set everyone up for success, so here’s the lowdown on how we hire. Our process is a two-way street – bringing you into our culture, while helping us learn how you think.

Our full process can last about eight weeks from application to offer, because we care about getting it right. These steps explain how we usually do things.

Before you get started, feel free to consider if you want to work with us. Strange question? Well, we give people a lot of space to navigate their day-to-day and that style isn't for everyone. We want you to be passionate about what you do and be sure this is the right fit. Because when skills and passion combine – it creates that 'Wow' moment.