Staff Full Stack Engineer - Buy-Side Growth

📈 Who We Are

We are rebuilding the energy transaction, making it transparent and fair.

We're rebuilding how energy is bought and sold. That means cutting out middlemen, connecting businesses directly with renewable generators, and ensuring every transaction is traceable and transparent.

We're a 160+ person team - operators, data scientists, engineers, customer champions and energy experts - backed by top-tier investors including Lightspeed Venture Partners, Hitachi Ventures, Allianz, AlbionVC and Atomico. We closed a $75M Series B round in early 2026, taking our total funding to $94M, and we now power energy for over 4,000 UK businesses across 8,500+ sites, with over £75m in value returned to businesses and generators so far.

We're a technology company solving the energy industry, not an energy company. Some people call us a neo-utility, the neo-bank idea, applied to energy.

The industry is noticing. We were crowned Europe's Most Exciting Tech Company at the GP Bullhound Allstars awards [link for members] came in at #6 on LinkedIn's Top Startups 2026 [link for members] in the UK, #7 on the Scaling Europe 50 [link for members] of Europe's fastest-growing companies, and #14 on Sifted's AI 100 [link for members]

Learn more about us on our website [link for members]

🏅 THE ROLE

We're hiring a Staff Full Stack Engineer to act as embedded technical leader for one of Buy-Side Growth's engineering squads.

Buy-Side is organised into four dedicated squads, each built around a single technical leader: Self-Driving Tendering, Price Everywhere, Broker Self-Serve, and Customer Autopilot, supported by a cross-squad Architect who owns the Buy Engine and tendering service. Two of those squads - Broker Self-Serve and Customer Autopilot - don't yet have a technical leader in place, which is the clearest gap in the team today. This role exists to close that gap: to be the person a squad looks to for architecture calls, technical direction, and the judgement to pick the right bets, without needing to be a people manager to do it.

The bigger picture: Buy-Side's vision is an engine that increasingly runs itself - agents handling tendering, pricing, and customer experience end to end, so the team can serve many more brokers and customers without headcount scaling in step. You'll be building directly toward that, on a team that already ships in dedicated, focused squads rather than one team context-switching across everything.

In your first 12 months, you might

• Step in as the embedded technical leader for a squad - most likely Broker Self-Serve or Customer Autopilot, both currently short a technical lead.

• Take Customer Autopilot from pre-discovery to a shipped first version, setting its technical direction from scratch.

• Extend the multi-broker tendering work that Self-Driving Tendering has already shipped, or push further into Price Everywhere, currently the team's biggest strategic bet.

• Mentor the engineers around you, raising the technical bar for your squad through code review, architecture proposals, and the credibility of your own delivery.

• Help design the agentic workflows that let Buy-Side handle dramatically more tenders and customers per person than it can today.

🚀 RESPONSIBILITIES

• Build with impact: Architect and deliver end-to-end systems, from internal automation to broker- and customer-facing portals, ensuring they are scalable, fast, and user-friendly.

• Lead the technical direction: Propose and own the technical direction for your squad, picking the right architectural bets and building the credibility to get others to act on your recommendations.

• Own the platform: Improve and extend core platforms and tooling, making it easier for your squad and others to build, test, and ship quality software.

• Drive innovation: Rapidly prototype and iterate on new workflows and product ideas that expand our offering and improve the broker and customer journey.

• Raise the bar: Mentor other engineers and teach your domain through code reviews and hands-on collaboration, without needing a formal management line to do it.

🎯 REQUIREMENTS

Must-Haves

• Strong technical leadership: a track record of setting technical direction for a team or project, and getting others to commit to it through the credibility of your work, not through a management title.

• Track record in fast-paced environments: experience as a Senior or Staff Engineer in a high-growth startup or scale-up, with a strong bias toward shipping.

• System design at scale: proven ability to design and build complex systems that power both back-end automation and front-end experiences.

• Modern tech expertise: it's preferred that someone has deep experience with Python (FastAPI) and modern JavaScript/TypeScript frameworks such as React, however we're open to people who demonstrate the ability to be tech agnostic.

• Product-minded: experience participating and leading customer discovery calls in translating user needs into feature ideations, following the end-to-end lifecycle of a product offering.

• Can deal with ambiguity: comfortable navigating changing priorities and incomplete information to make strong technical decisions, particularly useful for a squad like Customer Autopilot that's still pre-discovery.

Desirable

• Agentic or agent-building experience: exposure to designing multi-agent workflows or systems, which is central to Buy-Side's long-term direction.

• Exposure to the energy sector or other regulated industries.

• Experience building internal tools or platforms for brokers, sales teams, or support agents.

• Familiarity with real-time data processing systems.

✨ BENEFITS & PERKS

• Competitive salary - our current band for this role is £104,000 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 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 (75 Mins). You’ll meet with potential peers in this session and will discuss technical topics and experiences.

• 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 the company.

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.