Senior Staff 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, 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 a Senior Staff Software Engineer to help evolve one of the most critical platforms at tem. This platform powers complex commercial workflows across forecasting, pricing, optimisation, and deal execution - sitting directly on the path between customer demand and revenue generation. The systems behind it combine high-throughput event processing, stateful workflows, distributed decision-making, and machine learning models operating in production. You’ll work on large-scale backend and platform engineering problems where correctness, reliability, and operational clarity matter deeply. The domain is complex, the stakes are high, and the technical challenges span architecture, scalability, workflow orchestration, data modelling, and developer productivity. This is a hands-on Staff+ role for someone who enjoys building robust systems in ambiguous environments, driving execution across teams, and shaping technical direction through delivery.

Responsibilities:

• Lead Through Execution: Drive major technical initiatives from design through production, improving scalability, reliability, and correctness across critical systems.
• Build Distributed Systems: Design and evolve backend services, APIs, event-driven workflows, and data models that support complex business processes at scale.
• Own Critical Platform Infrastructure: Improve the operational foundations of the platform through better observability, testing, deployment safety, and incident reduction.
• Solve Complex Workflow Problems: Design systems that handle long-running workflows, asynchronous processing, consistency guarantees, and failure recovery in high-stakes environments.
• Work Across Teams: Lead initiatives spanning engineering, product, data, commercial, and machine learning teams - aligning stakeholders and unblocking delivery.
• Productionise Machine Learning: Collaborate with ML and data teams to safely integrate forecasting, optimisation, and pricing models into production systems.
• Raise Engineering Standards: Mentor senior engineers, influence architectural direction, and improve engineering practices across the organisation.
• Design for Scale: Anticipate scaling challenges before they emerge - improving throughput, resilience, and platform evolution as the business grows.

Requirements:

Must-Haves:

• Strong Technical Leadership: You’ve operated at Staff or Senior Staff level and have led technically complex initiatives with meaningful business impact.
• Distributed Systems Expertise: Deep experience designing and operating scalable backend systems, event-driven architectures, APIs, and asynchronous workflows.
• Hands-On Engineering Depth: You still enjoy building software directly - writing production code, reviewing designs, debugging systems, and improving architecture.
• Modern Backend Experience: Strong experience with technologies such as Python, AWS (Lambda, API Gateway, DynamoDB), Event-driven/serverless architectures, Distributed systems and workflow orchestration.
• Systems Thinking: You’re comfortable reasoning about correctness, failure modes, data consistency, scalability, and operational trade-offs in complex systems.
• Cross-Functional Influence: You can align technical decisions with product, commercial, and customer outcomes while navigating ambiguity effectively.
• Pragmatic Problem Solving: You enjoy untangling difficult technical and organisational problems using first-principles thinking.

Desirable:

• Experience with high-scale infrastructure or performance-sensitive systems.
• Background in platform engineering or internal developer platforms.
• Exposure to workflow engines, orchestration systems, or real-time decision systems.
• Experience integrating ML models into production environments.
• Familiarity with regulated industries such as energy, fintech, or govtech.
• Experience evolving systems from startup scale to multi-product platforms.
• Knowledge of Kubernetes, Spark, or large-scale data systems.

Benefits & Perks:

• Competitive salary - 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 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 Interviews with the Team (2 x 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.