Senior Full Stack Engineer - Sell Side Growth

📈 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 hiring a Senior Full Stack Engineer to join the Sell-Side Growth engine. Sell-Side owns the entire generator customer lifecycle at tem - from origination, through pricing and contracting, to onboarding, renewal, and retention. It's a small, fast-moving engine (an engineering team growing from 5 to 8) working directly with renewable generators across AD, wind, solar, and hydro, and everything the team ships shows up directly in GWh signed. This is a broad, cross-cutting role. You'll help build the systems that let generators and brokers get priced, contracted, and onboarded with less manual effort, and you'll work closely with Commercial, Product, and Rosso (tem's pricing engine) to do it. One live example: some of our larger generators don't want a fixed price per MWh, they want flex - and flex doesn't fit cleanly into tem's engineering architecture today. Making that work is a genuinely company-wide project, not a contained feature, and it needs someone who can build it and bring other teams along with them. In your first 12 months, you might: - Help design and ship tem's first flex pricing product, working across engine boundaries with Rosso and Commercial to make it fit. - Help automate the tendering and pricing-email workflow, removing a manual bottleneck that currently slows down every broker deal. - Build renewals tooling - proactive nudges and dashboards - that protects the renewal rate compounding our GWh signed. - Give the team real pipeline visibility through sell-native dashboards, so deal velocity and technology mix are visible day to day. - Contribute to multi-site deal tooling (Fix & Mix), which is already unlocking near-1TWh deals the current manual process can't support. 🚀 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 how generators and brokers interact with our platform. - Improve how we ship: Contribute to the automation, tooling, and workflows that let a small engineering team support a fast-growing generator book. - Collaborate cross-functionally: Partner with Commercial, Product, and Rosso to design solutions to problems that don't sit neatly inside one team - and communicate clearly enough to bring senior stakeholders along with you. - 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. - Strong backend fluency: solid experience with Python, and comfortable being the primary owner of backend systems rather than splitting time evenly with the front end. - Cloud-native skills: experience with AWS services, especially serverless tools like Lambda, API Gateway, and DynamoDB. - Strong communication and influence: comfortable explaining trade-offs to and winning buy-in from senior, non-technical stakeholders across the business, not just within your own team. - A user-focused mindset: comfortable turning generator, broker, and commercial problems into simple, elegant technical solutions. - Team-first approach: experience working in cross-functional teams where Engineers, Commercial, and Product collaborate closely. Desirable: - Exposure to flex trading, energy trading, or payments - genuinely useful, not a dealbreaker. - 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 £82,700 or equivalent in local currency. - We pay against a clear benchmark for your role and level. No fixed once- or twice-a-year cycle - pay moves when the evidence for it does. - 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. 1. First call with our Talent Team (30 Mins). This is to understand your experience, motivations, and discuss the role in more detail. 2. 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. 3. Technical Interview with the Team (90 Mins). You’ll meet with potential peers in this session and will discuss technical topics and experiences. 4. Bar Raiser 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.