Principal Engineer

London hybrid Until 10/7/2026 First posted April 13, 2026 Last posted August 8, 2026
Job description

MOO is all about making great design available to everyone. We do that by producing premium print and branded merchandise. But it’s as much about how we do it, leading with design, technology and sustainability.

Founded in 2004, we’ve come this far by being obsessed with the happiness of our customers.  Along the way, we’ve built an award-winning and much-loved brand, with exceptional customer satisfaction and Trustpilot ratings. Those customers are typically small and medium-sized businesses based in North America, the UK, and Europe – businesses that, like us, value design and see the brand-building power of putting something real in people’s hands.  

We’ve received the highest business award in Britain, ‘The Queen’s Award for Enterprise’. Part of Tech Nation’s ‘Future Fifty’, we’ve been profiled in the Financial Times, and ranked in the Guardian’s top 10 UK start-ups.

Today we are over 350 people, headquartered in the UK but with many of our people based in the USA and South Africa.


We’re making new and exciting things – and we could really do with your help.
 
MOO’s Post‑purchase domain spans the physical and digital worlds: order orchestration, manufacturing, fulfilment, shipping and customer support tooling. As we scale, we’re consolidating tooling for CS and Ops, improving data visibility across the order journey, integrating new carriers, and increasing throughput in manufacturing while protecting customer experience and margin. You’ll partner closely with Nexus and Forge teams to deliver a coherent, scalable architecture and unblock cross‑team delivery.
 
We are looking for someone who is able to work 2-3 days a week out of our Camden office, with potential travel to RI< USA to work with our Manufacturing team.
 
 

The Role

  • As a Principal Engineer, you'll provide technical leadership across a broad area of the engineering organisation.
  • You'll partner with Engineering Managers, Staff Engineers, Product Managers and senior stakeholders to define architectural direction, influence technical strategy, and solve complex engineering challenges.
  • You'll balance long-term architectural thinking with pragmatic delivery, helping teams evolve existing systems while enabling the development of new capabilities.
  • You'll play a key role in raising engineering standards, mentoring senior engineers, and ensuring our technology continues to scale alongside the business.

Responsibilities

    Technical Leadership & Strategy

    • Define and evolve architectural direction across multiple teams and systems.
    • Drive technical strategy that supports business objectives while balancing long-term sustainability with delivery.
    • Identify opportunities to simplify systems, reduce technical debt and improve developer productivity.
    • Architecture & Engineering Excellence

      • Design scalable, resilient and observable distributed systems.
      • Establish architectural principles, standards and engineering best practices.
      • Lead technical design reviews and guide complex technical decision-making across teams.
      • Cross-functional Collaboration

        • Partner closely with Product, Engineering and business stakeholders to translate strategic goals into technical solutions.
        • Help teams navigate complex technical challenges and align on pragmatic approaches.
        • Drive cross-team initiatives that improve platform capabilities and accelerate delivery.
        • Mentorship & Technical Leadership

          • Mentor Staff Engineers, Senior Engineers and engineering leaders, supporting their technical growth.
          • Foster a culture of engineering excellence, knowledge sharing and continuous improvement.
          • Act as a trusted technical advisor across the organisation.

About You

  • Significant experience designing and evolving large-scale distributed systems in modern cloud environments.
  • Proven track record of influencing architecture and technical direction across multiple teams or business domains.
  • Strong understanding of software architecture, event-driven systems, APIs and modern engineering practices.
  • Comfortable balancing strategic architectural work with hands-on technical leadership.
  • Excellent communication and stakeholder management skills, with the ability to influence both technical and non-technical audiences.
  • Experience mentoring senior engineers and building strong engineering cultures.
  • Passionate about solving complex problems while keeping customer and business outcomes at the centre of technical decisions.

Nice To Haves

  • Experience working within e-commerce, SaaS or high-growth technology businesses.
  • Experience with cloud-native architectures and platforms such as AWS.
  • Knowledge of observability, platform engineering and developer experience.
  • Experience leading large-scale migrations or modernisation programmes.
  • Familiarity with event-driven architecture, distributed systems and domain-driven design.

Outcomes You Will Drive

  • A clear, scalable architectural vision that enables engineering teams to move quickly and confidently.
  • Improved platform reliability, performance and operational excellence.
  • Increased engineering velocity through better tooling, standards and technical practices.
  • Stronger cross-team collaboration and alignment on technical direction.
  • A culture of technical excellence, mentorship and continuous improvement that enables teams to build for the future.
What’s it like to work at MOO? 
MOO’s the kind of workplace where you can really be yourself. Dye your hair purple. Hit the sofa with your laptop. Whatever helps you feel comfortable and happy at work. We want to help you grow in your career and set you up for success – while also recognising the importance of a healthy work/life balance.
 
That’s why we offer 25 days holiday rising by one day for each year here (for 5 years), a matched pension scheme, and paid parental leave. We’ll offer you private healthcare, life insurance, a season ticket loan, and a cycle to work scheme. We also offer flexible work schedules with hybrid and remote working for certain roles as well as a Work From Anywhere program.
 
Diversity Statement
We are working hard to create a representative, inclusive and super-friendly team, because we know that different experiences, perspectives and backgrounds make for a better workplace. And that creates a better experience for our customers. MOO doesn’t discriminate on the basis of race, colour, religion or belief, gender, national origin, age, sexual orientation, marital status, disability or any other protected class.
 
As a design and technology company we have a desire and a responsibility to build a business that represents the world around us. So we strive to create a values-driven, purposeful and highly empowered organisation that we are all proud to work for. And we are committed to continuous investment in building an open and inclusive environment, welcoming a diverse audience of candidates who see themselves working and thriving at MOO. Therefore, we’d like to invite you to complete this optional survey to help us evaluate our inclusion and diversity efforts. Completing this form is entirely voluntary and if you decide not to it won’t in any way affect your job application. We keep the information separate from your application and it is kept secure and confidential, it is only used to better our inclusion and diversity efforts. By submitting this information, you consent to MOO's processing of it for these purposes.
About this role

Summary

Lead technical strategy and architecture for scalable, resilient systems across teams.

Job title

Principal Engineer

Experience level

significant experience

Industry

print and design

Location requirements

London-based, hybrid work, possible travel to USA

Salary

Not specified

Management role

No

Skills & keywords

Required skills

distributed systemscloud environmentssoftware architectureAPIstechnical leadership

Preferred skills

e-commerceSaaSAWSobservabilitydomain-driven design

Specializations

distributed systemscloud environmentsarchitectureAPIsevent-driven systems
Locations

Structured locations inferred from the posting.

London, UK

Hybrid City