Principal Engineer - Contract - Outside IR35

London, England, UK on site Until 8/26/2026 5+ years exp First posted June 27, 2026 Last posted June 27, 2026
Job description

We are currently looking for an experience Principal Engineer to join us on a contract basis.

This is a hybrid position and will require 3 days per week on client site in Central London.

Requirements

Role responsibilities:

  • Define and drive technical strategy, architecture, and engineering standards across the Personalisation domain
  • Design and deliver scalable systems supporting personalisation, search, recommendations, and ML-powered features
  • Partner closely with Product, Data Science, and Design to deliver customer-centric solutions
  • Lead and influence technical decision-making across multiple teams and platforms
  • Mentor and support senior engineers, helping to raise the overall engineering capability
  • Improve engineering quality, reliability, and productivity through best practices, tooling, and platform enhancemen

Who you are:

  • An experienced technical leader with a strong background in Java/Python and large-scale production systems
  • Strong experience working with Machine Learning systems and collaborating with Data Science teams
  • Skilled in system design and architecture, with the ability to deliver scalable, high-quality solutions
  • Comfortable working across cross-functional environments with multiple stakeholders
  • Passionate about growing others and driving engineering excellence
  • A strong communicator who can influence technical and business decisions at all levels"
About this role

Summary

Lead system design, architecture, and ML initiatives; mentor engineers; influence decisions.

Job title

Principal Engineer - Contract - Outside IR35

Experience level

senior level

Minimum experience

5+ years exp

Industry

software

Location requirements

hybrid in London, remote if preferred; 3 days/week onsite

Salary

Not specified

Management role

No

Skills & keywords

Required skills

javapythonsystem designarchitecturemachine learning

Preferred skills

leadershipstakeholder managementscalabilitycollaboration

Specializations

system designarchitecturemachine learningscalabilitycollaboration
Locations

Structured locations inferred from the posting.

London, UK

Hybrid City