Senior Software Engineer (BackEnd)

NextGenEnergyJobs; Greater London; Hybrid; GBP 90,000 - 130,000; Full time

Job summary

NextGenEnergyJobs is seeking a Senior Fullstack Software Engineer (Python and React) to join our product and engineering team building the systems powering our electric car leasing platform.

You will design robust APIs, evolve backend data models for performance, and contribute to frontend work when needed, while championing maintainable code and collaboration across disciplines.

Qualifications

• Deep expertise in Python with strong software engineering fundamentals.
• Experience designing and building APIs, ideally with GraphQL.
• Experience with relational (PostgreSQL) and NoSQL databases.
• Strong understanding of software engineering principles and scalable, maintainable systems.
• Proven experience collaborating within teams across disciplines.
• Experience using AI tools to augment development.
• Track record of ownership from inception through delivery.

Responsibilities

• Design and build robust APIs integrating services to automate core processes.
• Architect and evolve backend systems and data models for performance and scalability.
• Work across multiple data sources, designing expressive schemas.
• Contribute to frontend applications when needed, improving user experiences.
• Write maintainable code with long-term quality.
• Share knowledge, mentor others, and raise the team’s capability.

Skills

Python

API design

Team collaboration

Ownership

AI tooling

Tools

GraphQL

PostgreSQL

Job description

We’re looking for a Senior Fullstack Software Engineer (Python and React) to join our product and engineering team building the systems that power our ability to revolutionize the electric car leasing industry.

Responsibilities

• Design and build robust APIs, integrating our own and third-party services to optimise and automate core business processes.
• Architect and evolve backend systems and data models that are performant, scalable, and built to last.
• Work across multiple data sources, designing expressive, well-structured schemas.
• Contribute to frontend applications when needed, helping shape experiences that work well for our users.
• Care about the code you write and its long-term maintainability.
• Contribute ideas, share knowledge, support, mentor, and raise the game of those around you.

Requirements

• Deep expertise in Python, with strong software engineering fundamentals.
• Proven experience designing and building APIs, ideally using GraphQL.
• Comfort working with multiple data sources, including relational (PostgreSQL) and NoSQL databases.
• Excellent understanding of core software engineering principles and best practices, and a track record of applying them to build robust, scalable, maintainable systems.
• Proven experience collaborating within teams and across disciplines.
• Experience using AI tech and tooling to augment development
• A track record of taking ownership of features from inception through to delivery.

Benefits

• Don't feel like you meet all of our hiring criteria? thats OK,
• Octopus Electric Vehicles , part of the Octopus Energy Group, won the Sunday Times best company to work for in 2024. We were named 6th out of the top 100 start-ups to work for by Tempo in 2025 and on Glassdoor we were voted 50 best places to work in 2022 . Our Group CEO, Greg has recorded a podcast about our culture and how we empower our people
• Wondering what the salary for this role is? Just ask us! On a call with one of our recruiters it's something we always cover as we genuinely want to match your experience with the correct salary. The reason why we don't advertise is because we honestly have a degree of flexibility and would never want salary to be a reason why someone doesn't apply to Octopus - what's more important to us is finding the right octofit!
• Octopus Energy Group is a unique culture . An organisation where people learn, decide, and build quicker. Where people work with autonomy, alongside a wide range of amazing co-owners, on projects that break new ground. We want your hard work to be rewarded with perks you actually care about! Visit our perks hub - Octopus Employee Benefits