Senior Full Stack Engineer

📈 Who We Are: We are rebuilding the energy transaction, making it transparent and fair. Our goal is to put power back where it belongs, in the hands of customers and to take on one of the most critical problems of our century, access to low cost electricity. tem exists to fix a broken global energy market that’s long favoured legacy operators, intermediaries, and opaque pricing. Today’s electricity system was not designed for rapid decarbonisation, AI-driven efficiency or fair access for the actual users - businesses and generators. We’ve built the first AI native transaction infrastructure to reinvent how electricity is bought, sold and priced. Our technology is designed to cut out the inefficient fees, automate complex market flows, and bring transparency and fairness to energy transactions at scale. In late 2025, after extraordinary growth, we closed a $75 million Series B - led by Lightspeed Venture Partners with participation from Albion, Atomico, Allianz, Hitachi Ventures, Hitachi Ventures, Schroders Capital and others - positioning us for global expansion, deeper product innovation and category leadership. We’re scaling internationally and building toward a future where AI-driven infrastructure is foundational to electricity markets worldwide. Since launch, our modern utility product, known as RED, has already facilitated thousands of business customers and billions in energy transaction value, proving that modern software and AI can transform an industry built on legacy systems. At tem, we’re not just building another energy company, we’re rearchitecting market infrastructure so that transparency, efficiency and sustainability become the default, not the exception. 🏅 The Role: We’re looking for Senior Full Stack Engineers to design and build the systems that power tem's core products and internal platforms. We’re hiring across several teams - including Platform, Billings, Payments, Customer Acquisition, and Customer Success - all of which play a critical role in how we deliver seamless, modern energy technology. As a Senior Engineer, you’ll help shape the architecture and build the features that enable brokers, customers, and internal teams to work smarter and faster. Depending on your team, this could mean anything from enhancing developer tooling and shared services, to building scalable billing and payments infrastructure, to delivering intuitive customer-facing experiences that support acquisition and retention. In your first 12 months, you might: Lead development of customer- and broker-facing portals that make complex energy workflows simple. Build and evolve billing and payments systems that are reliable, transparent, and ready for scale. Improve developer experience and platform foundations - including tooling, CI/CD, shared services, and automation. Streamline internal operations through intelligent workflows, dashboards, and integrations. Across all teams, you’ll be joining a group that values ownership, clarity, and impact - and you’ll play a key role in building the systems that enable us to grow rapidly and serve customers exceptionally well. 🚀 Responsibilities: Build with impact: Develop full-stack features across modern front-end frameworks and serverless back-end systems, with a focus on performance, reliability, and usability. Shape the experience: Build intuitive, high-quality interfaces and tools that improve the way customers and brokers interact with our platform. Improve how we ship: Contribute to internal tooling, frameworks, and engineering workflows that help us deliver faster and with greater confidence. Collaborate cross-functionally: Partner with Product, Design, and other Engineers to design thoughtful, user-centred solutions to complex problems. Maintain high standards: Write clean, well-tested code, contribute to code reviews, and help improve team practices and documentation. 🎯 Requirements: Must-Haves: Proven product delivery experience: Experience as a Full Stack Engineer in a startup or fast-paced product environment, with ownership of key projects from start to finish. Front- and back-end fluency: Strong experience with Python and/or Node.js, and modern JavaScript frameworks like React. Cloud-native skills: Experience working with AWS services, especially serverless tools like Lambda, API Gateway, and DynamoDB. User-focused mindset: Comfortable turning product and user problems into simple, elegant technical solutions. Team-first approach: Experience working in cross-functional teams where Engineers, Designers, and Product Managers collaborate closely. Desirable: Experience building platforms or tools for brokers, sales partners, or operational teams. Exposure to the energy sector or other regulated industries. Familiarity with real-time data systems or internal workflow automation. ✨ Benefits & Perks: Competitive salary - our current band for this role is £81,300 or equivalent in local currency. We review salaries twice a year using real-time market data, with transparent, consistent pay for the same role and level. Stock Options - everyone on the team has ownership in our mission. 25 days holiday + public holidays - Swap public holidays for ones that matter most to you. Plus, get an extra day off for your birthday 🎉. Remote & flexible working - We’re fully remote, distributed across Europe with clear core hours, and no internal meetings on Friday afternoons. Home working & wellbeing budgets : Up to £1,200 / €1,200 annually to upgrade your remote setup (co-working passes, equipment, etc.). Up to £150 / €150 monthly on anything that supports your wellbeing - from therapy to gym memberships to meditation apps. 🗣️ Interview Process: Our processes normally take around 2-3 weeks from first call to offer - please let us know about any adjustments to timelines that may be required. First call with our Talent Team (30 Mins). This is to understand your experience, motivations, and discuss the role in more detail. Behaviour Interview with our Engineering Managers (60 Mins). This is your chance to really understand the role, the expectations, and ensure alignment on ways of working. Technical Interview with the Team (90 Mins) . You’ll meet with potential peers in this session and will discuss technical topics and experiences. Culture-Add Interview with Stakeholders (45 Mins). The final session will be with two cross-functional stakeholders, and will explore how your values align with ours, and is designed to be a genuine two-way conversation, your chance to understand what it’s really like to work at tem. We welcome applications from people of all backgrounds, experiences, and identities, including those that are traditionally underrepresented in the tech and energy sectors. If you’re excited about this role but not sure you meet every requirement, we’d still love to hear from you. Your unique perspective could be exactly what we’re looking for.