Senior Staff Full Stack Engineer in London

Who We Are: We have built the new way for energy to be transacted. tem exists to fix a creaking energy market. Today's wholesale system is stacked in favour of the few - a relic of the oil and gas era, riddled with markups and middlemen. We're changing that. Our product, RED™, is built on a proprietary pricing engine that bypasses the wholesale market, enabling businesses to buy energy produced by renewable generators directly. That means clear, auditable transactions that ensure affordable bills and fair compensation - giving every business real ownership and control over where their energy comes from. Since launching in 2021, we've saved UK businesses and generators over £25 million, powering a growing network of forward-thinking companies, from Pizza Pilgrims to Silverstone. Backed by top-tier VCs including Atomico and Albion, we're creating a new category in energy - one that's decentralised, direct, and built on trust.

The Role: We’re looking for a Senior Staff Engineer to shape the technical direction of our customer acquisition and customer success platforms, accelerating product delivery while building the architectural foundations for long-term scale. This is a company-level technical leadership role. You’ll operate as a force multiplier across multiple teams — setting architectural vision, driving cross-platform initiatives, and ensuring our systems are resilient, extensible, and built for rapid growth.

In your first 12 months, you’ll lead the design and delivery of foundational systems that redefine how brokers, customers, and internal teams interact with energy services — from real-time pricing and quoting engines to intuitive self-serve platforms and intelligent internal tooling. You’ll partner with Engineering, Product, and Leadership to ensure we are building the right systems, in the right way, for the next stage of our growth. This role combines deep hands-on engineering with strategic technical ownership and organisational influence.

Responsibilities:

• Set Technical Direction: Define and evolve the architecture across our acquisition and success platforms, ensuring scalability, resilience, and clarity of ownership across teams.
• Drive Multi-Team Initiatives: Lead complex, cross-functional engineering efforts that span teams and systems — aligning stakeholders, reducing ambiguity, and delivering high-leverage outcomes.
• Build & Ship: Remain deeply hands-on — designing, coding, and reviewing critical components across back-end systems, APIs, infrastructure, and front-end applications.
• Strengthen Foundations: Improve platform reliability, developer experience, observability, testing strategy, and deployment practices to enable faster, safer shipping across the organisation.
• Accelerate Product Innovation: Partner closely with Product and Design to translate ambiguous problem spaces into scalable technical solutions, balancing speed with long-term quality.
• Multiply Impact: Mentor Staff and Senior Engineers, raise engineering standards, and act as a trusted technical advisor to leadership.
• Plan for Scale: Anticipate bottlenecks before they emerge — proactively designing systems, processes, and data flows that support rapid company growth.

Requirements:

Must-Haves:

• Senior technical leadership experience: Experience operating at Staff+ or Senior Staff level in a high-growth startup or scale-up, with clear evidence of organisation-wide impact.
• Architectural depth: Proven ability to design and evolve complex distributed systems spanning APIs, event-driven workflows, data systems, and front-end applications.
• Multi-team influence: Experience leading cross-team initiatives and driving alignment across engineering, product, and business stakeholders.
• Modern tech expertise: Deep experience with Python and/or Node.js, AWS serverless architecture (Lambda, API Gateway, DynamoDB), event-driven systems and asynchronous workflows.
• Strong front-end fluency: Confident architecting and building modern, performant React applications that integrate seamlessly with complex back-end systems.
• Product & business alignment: Demonstrated ability to connect technical decisions to business outcomes and customer experience.
• Navigating ambiguity: Comfort operating in evolving environments, defining direction where it doesn’t yet exist.

Desirable:

• Experience scaling systems from early product-market fit to multi-product platforms.
• Exposure to regulated industries (e.g., energy, fintech, govtech).
• Familiarity with real-time pricing engines, workflow orchestration, or AI/agentic systems.
• Experience improving engineering org design, team topology, or platform strategy.

Benefits & Perks:

• Competitive salary - our current band for this role is £129,500 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 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.