Senior Frontend Engineer

We're making energy fair, clean, and simple for all using technology. Octopus Energy started with a bold idea: to build Britain’s first truly digital energy supplier. By combining world-class tech with brilliant humans who care deeply about customers and driving the renewable energy transition, we made it happen and in 2025, we became Britain’s largest energy supplier. Octopus Energy Group is a global energy transition collective.

10 businesses working across 4 continents to tackle energy transformation at nearly every front. And we constantly push to make energy better. Tirelessly campaigning for fair protections for customers. And building innovative technologies that forge a path to a green energy system. We’re made up of 10,000+ authentic, committed people working around the world on stuff you'd never expect. We're united by a shared goal: to drive the global green energy revolution.

Read our Spotlight series to meet some of the team. We are looking for a Senior Frontend Engineer to join our Flexibility team. The Flexibility team was established in early 2026, and has been growing throughout the year. The team is focused on greenfield opportunities at the cutting edge of Octopus' flexibility strategy, and aims to enable rapid response to global flex opportunities.

They are building the next generation of products and tools to make energy more flexible. These include our flagship Intelligent Octopus product automating demand shift for 300,000 customers with electric cars, home batteries or smart heating devices, saving 2 million customers money through Saving Sessions and Free Electricity Sessions, and managing 568MW of large grid-scale batteries to balance the system.

The team develops products that are used by millions of customers, helping boost renewables use and decarbonise energy systems worldwide. We embrace flat hierarchies and an open, agile culture that fosters innovation, flexibility, and creativity. We don’t hang our personalities up with our coats and nor should you. At Octopus, we hire great people who get stuff done, all whilst being themselves.

What you'll do

• Acting as the flexibility team’s first frontend engineer, establish the team’s frontend capability, lead the team’s frontend technical direction and represent the team to the cross-team community of frontend engineers

• Build and own a diverse range of customer-facing user journeys, enabling customers to onboard, control, and analyse their low carbon tech

• Build and own internal-facing interfaces for stakeholder-collaborators and experimental prototypes

• Interface with established mobile teams by providing Web Views for emerging mobile customer journeys

• Collaborate with our internal design team to integrate our designs into the wider Octopus design system ‘Coral’

• Carry out product discovery by working closely with our Product Manager and stakeholders from across the organisation

• Build highly reusable interfaces that enable rapid response to new opportunities

• 5+ years of experience with our stack (listed below)

• Experience taking problems, rather than strict guidelines, and developing strong solutions

• Confidence owning the development cycle (request, requirements gathering, technical proposal, technical execution, deployment and monitoring.)

• Confidence tackling large-scale tasks individually

• An empathetic approach to delegating work and collaborating with others

• The ability to develop websites that meet strong accessibility guidelines

• Experience building scalable, performant sites that handle high levels of traffic well

• Desirable: energy domain knowledge

• React (required)

• Type Script (required)

• Next.js on Vercel (desirable)

• GraphQL w/ Tanstack Query (desirable)

• React Testing Library & vitest and/or msw (desirable)

We have a preference for candidates who can work hybrid from our London office, but we're open to fully remote candidates (you do need to be based in the UK).

• 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…