Senior Engineer I

Core responsibilities:

• Design, build, and maintain scalable backend services using TypeScript and Node.js
• Work with event-driven systems and message queues to power real-time, reliable features
• Collaborate with product managers, designers, and other engineers to build customer-focused solutions
• Lead by example — contributing to high-quality code, mentoring others, and fostering best practices
• Own services end-to-end, from architecture to production monitoring and continuous improvement
• Optimise system performance and data design, working with SQL or NoSQL databases as appropriate
• Leverage cloud platforms (especially AWS) and serverless architectures to build reliable, scalable solutions
• Contribute to a positive engineering culture by sharing knowledge and supporting your team

This role helps accelerate the shift to a clean, electrified future by building technology that makes clean energy dependable, affordable and adaptive to everyday life, supporting decarbonisation efforts globally.

Required skills and experience:

• Solid experience developing backend applications, ideally in TypeScript or a willingness to pick it up quickly
• Understanding of event-driven systems and working with queues
• Extremely comfortable working with cloud infrastructure (AWS preferred), especially serverless technologies
• Experience with database design, optimisation, and maintenance (SQL or NoSQL)
• Passionate about high-quality software and solving real customer problems
• Strong communication and collaboration skills — you enjoy mentoring and knowledge sharing
• Proactive mindset and ability to thrive in ambiguity

Compensation and benefits:

• Salary: £60,000 - £81,000
• Pension Scheme
• Discretionary Bonus Scheme
• Private Medical Insurance + Virtual GP
• Life Assurance
• Access to Furthr - a Climate Action app
• Free Mortgage Advice and Eye Tests
• Perks at Work - access to thousands of retail discounts
• 5% Flex Fund to spend on the benefits you want most
• 26 days holiday
• Flexible bank holidays, giving you an additional 8 days which you can choose to take whenever you like
• Progressive leave policies with no qualifying service periods, including 26 weeks full pay if you have a new addition to your family
• Dedicated personal learning and home office budgets
• Flexible working — we trust you to work in a way that suits your lifestyle

Kaluza is the Energy Intelligence Platform, turning energy complexity into seamless coordination. They help energy companies overcome today's challenges while accelerating the shift to a clean, electrified future by orchestrating millions of real-time decisions across homes, devices, markets and grids.