Principal Software Engineer

Location:  London, Bristol or Edinburgh (hybrid, three days a week in the office)

Level: Principal Engineer TL2 / TL3

Team: Enterprise Architecture

Salary: £120,000 – £160,000 + discretionary bonus

Contract: Permanent

Reporting to: Director of Enterprise Architecture

Please note: This role requires an existing right to work in the UK . We can’t offer visa sponsorship, but we review sponsorship role by role, so keep an eye on our careers site for future opportunities.

About Kaluza

Kaluza is the Energy Intelligence Platform, turning energy complexity into seamless coordination. We help energy companies overcome today’s challenges while accelerating the shift to a clean, electrified future.

Our platform orchestrates millions of real-time decisions across homes, devices, markets and grids. By combining predictive algorithms with human-centred design, Kaluza makes clean energy dependable, affordable and adaptive to everyday life.

With teams across Europe, Asia and Australia, and a joint venture with Mitsubishi Corporation in Japan, we power leading companies including OVO, AGL and ENGIE, as well as innovators like Volvo and Volkswagen.

What you’ll do

As a Principal Software Engineer at Kaluza, you will be the leading technical authority for a major global product area comprising multiple modules. You will lead innovation on some of the most complex, ambiguous, and large-scale solutions, aligning them with target architecture standards and contributing to the creation of a scalable platform.

You’ll have a broad sphere of influence, enabling multiple teams and serving as a strategic partner to our architecture leadership team and our community of principal and staff engineers.

Your impact will come mostly from 'hands-off' work; you’ll not be expected to write code day-to-day. But for some challenges, you may need to dive into code-level design or help build a proof-of-concept.

What you’ll bring
Ideally, you’ll have:

• Architect modern distributed, cloud-based systems applying modern architecture and engineering practices in an enterprise software environment.
• Shape and influence technical vision and product roadmaps to align with business goals.
• Provide hands-on leadership, making appropriate technical choices to satisfy requirements.
• Mentor and guide engineers in delivering autonomous, loosely coupled distributed systems with proven architectural principles and patterns.
• Lead technical due diligence and make high-stakes decisions with confidence.
• Deliver results, influence diverse audiences, and orchestrate cross-functional solutions spanning multiple product features.
• Engage effectively with both technical teams and executive leaders.
• Work independently and collaboratively, bringing strong opinions while respecting others, communicating openly, and maintaining self-awareness with a continuous growth mindset.

What will set you apart 

• Experience enabling engineering teams to use AI and delivering AI/ML powered solutions.
• Demonstrable experience in architecting solutions in complex business domains, particularly interface design and data modelling, ideally with experience in AWS and API design.
• Proven track record delivering global B2B2C SaaS (energy or other mission‑critical industries).
• Success driving adoption of modern engineering practices (e.g. DevOps, CI/CD).
• Experience leading teams through significant changes in ways of working.
• Ability to ramp up rapidly in new domains and technologies.

Our Values

Five values guide how we work at Kaluza

• Play to win: Collective pride in decarbonising energy at scale.
• Solve the real problem: Cutting through complexity to focus on real-world outcomes.
• Build trust every day: Consistency, transparency and doing what we say.
• Own the outcome: Full accountability, wins and setbacks, without ego.
• Go further together: Collaboration, respect and different perspectives.

Our Perks

• Time off and family: 26 days’ holiday, plus 26 weeks’ full pay for new parents with no qualifying service period
• Health and security: Private medical insurance with virtual GP, life assurance, pension scheme, free mortgage advice and eye tests
• Pay and flexibility: Discretionary bonus, a Flex Fund of 5% [of salary] to spend on the benefits you want most, retail discounts through Perks at Work
• Growth and setup: Personal learning budget, home office budget
• Climate: Furthr, our climate action app

Come as you are

We want to meet people from all walks of life. The more inclusive we are, the better our work will be, and we recognise talent on merit and potential. If you’re excited about the role but don’t tick every box, we’d still love to hear from you.

Find out more on our careers page and LinkedIn . Our Applicant Data Protection Policy is here .