Senior Backend Engineer

tem

📈 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: Rosso is tem's core pricing infrastructure. It brings together forecasting, margin optimisation, and portfolio balancing to price energy tenders from first input through to signed contract — and keeps the portfolio healthy as we grow. It sits directly on the critical path for revenue. This is a rare role. We're looking for someone who combines Principal-level distributed systems depth with real, hands-on experience bringing ML models into production — and who does all of it in Python. That combination is genuinely uncommon, and we know it. You'll own the most complex technical deliveries in Rosso end-to-end: designing the system, writing the code, partnering with our Data Science and ML teams to get pricing and forecasting models running reliably in production, and setting the technical direction for how Rosso scales. You'll challenge the brief, commit to a direction under uncertainty, and be accountable for outcomes — not workstreams. If you've spent your career at the intersection of high-stakes backend systems and ML productionisation, and your instinct when given a hard problem is to get into it rather than frame it, this role was written for you. 🚀 RESPONSIBILITIES: * Own Rosso's most complex deliveries. Lead high-impact improvements across pricing and deal-flow workflows — improving correctness, operability, and scalability as volume grows. You drive these from first design through to production. * Bridge ML and production infrastructure. This is the heart of the role. Work directly with our Data Science and ML teams to bring forecasting, optimisation, and pricing models into Rosso's core workflows safely, correctly, and at scale. You'll co-own the design of how models integrate with production systems — not just the infrastructure wrapper around them. * Make architectural decisions that last. Design and evolve a stateful, event-driven Python system where business logic is the primary source of complexity. Set clear domain boundaries and prevent the drift that compounds over time. * Lead across teams. Drive cross-functional initiatives spanning engineering, product, data, ML, and commercial stakeholders. Align people around a technical direction and deliver. * Raise the bar. Mentor Staff and Senior Engineers, drive observability and testing standards, and act as a trusted technical voice to engineering leadership. * Plan for scale. Architect for high-volume quoting activity and large customer counts — anticipating bottlenecks before they surface in production. 🎯 REQUIREMENTS: Must-Haves: * You are a Python expert. Not just comfortable in Python — you have deep expertise in building and operating production Python systems at scale. You know the language's performance characteristics, packaging and dependency patterns, async and concurrency models, and you have opinions about how to build Python systems well. * You have genuine ML productionisation experience. You've worked at the boundary of ML and backend engineering — integrating models (forecasting, optimisation, pricing, or similar) into production systems, designing the infrastructure around them, and owning what happens when they fail or drift. This isn't coordination experience; it's hands-on engineering. * You operate at Principal level with organisation-wide impact. You've owned major technical initiatives at a high-growth startup and can point to what changed because of it. Not just influence — shipped outcomes with measurable business impact. * You have deep application architecture depth in complex domains. You've designed and evolved stateful distributed systems — APIs, event-driven architectures, data pipelines — where domain logic is the hard part. You know what domain drift looks like and how to prevent it. * You're strong with AWS serverless architecture. Hands-on experience with Lambda, API Gateway, DynamoDB, and event-driven, asynchronous workflows — operated in production and learned from failure. * You can drive to a concrete decision under ambiguity. You ask sharp questions to narrow the problem space, commit to a direction, and take responsibility for the outcome. You don't narrate a methodology — you execute one. * You connect technical decisions to business outcomes. Technical authority and business accountability aren't in tension for you — they're the same thing. Desirable: * Experience in real-time pricing engines, energy markets, or financial infrastructure * Exposure to regulated industries (energy, fintech, govtech) * Experience improving engineering team topology or platform strategy * High-performance/high-scale environments (Kubernetes, Spark, or similar) * Experience scaling systems from early PMF to multi-product platforms ✨ 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. 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 Rosso GM, hiring manage for this role (45 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. 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.

Thought Machine

Thought Machine's mission is bold – to properly and permanently rid the world's banks of legacy technology. To achieve this, we have developed the foundations of modern banking through core and payments technology which run natively in the cloud. What we are attempting is hard and means we need great people working together to build great technology. We have grown rapidly in the past few years – growing our team to more than 550 individuals across offices in London, New York, Singapore, Sydney and our newly established Engineering Hub in Lisbon. We have raised more than £500m in funding and our investors include Molten Ventures, Eurazeo, Intesa Sanpaolo, Temasek, Nyca Partners, JPMorgan Chase Strategic Investments, Standard Chartered Ventures, and more. We have created a culture that enables our team to produce the best work in the industry while ensuring we have fun along the way. We're regularly cited as having a fantastic workplace culture and have been recognised by Sifted magazine as having one of the highest Glassdoor ratings for a UK fintech company and the industry's most generous employee share package. Named one of the world's most innovative fintechs by Global Finance Magazine, we were also recognised by the Financial Times as one of Europe's fastest-growing companies for two consecutive years—and a UK Best Employer for 2026. As a Senior Software Engineer I at Thought Machine, you will own and deliver highly complex, end-to-end engineering work items. You will look beyond immediate coding tasks to consider long-term system architecture, product strategy, and client outcomes. In this role, you will act as a technical anchor for your team, solving ambiguous problems, guiding less experienced engineers, and actively shaping our technical and product roadmaps. This is a role for an engineer who values clean, maintainable systems, embraces an egoless approach to collaboration, and is driven to deliver robust solutions to production. WHAT YOU’LL DO Technical Leadership * Design & Build: Design and build highly reliable, secure, and scalable software solutions for complex problems. * Architecture & Standards: Contribute to team guidelines ensuring our services meet top-tier security, performance, cost, and reliability standards. * Code Quality & Peer Review: Set a high bar for code quality by providing constructive, detailed feedback on design documents and pull requests. * Operational Excellence: Investigate issues across multiple services in production, drive learning from operational incidents, and feed improvements back into our prioritisation process. * Hiring: Actively participate in our growth by leading technical interviews. Product & Delivery * End-to-End Ownership: Own work items from initial concept to production, creating structured delivery plans, managing dependencies along the way and owning delivery of these work items. * Product Vision: Partner with Product Managers to prioritize features, translate client requirements into technical specifications, and ensure solutions align with our overarching product vision. * Incident Management: Confidently own the resolution of incidents, coordinating mitigation, fixes, and post-mortem artifacts. Collaboration & Mentorship * Team Growth: Mentor and support less experienced engineers, helping them level up technically and adapt to Thought Machine’s engineering philosophy. * Stakeholder Management: Translate highly technical problems and architectural decisions into clear concepts for non-technical stakeholders. WHAT WE’RE LOOKING FOR * Technical Expertise: Strong proficiency in modern backend languages (ideally Go or Python) and experience building distributed, cloud-native systems (Kubernetes, AWS/GCP, gRPC, PostgreSQL). * Problem Solving: A proven track record of breaking down ambiguous, and complex problems into clear, deliverable milestones. * Production Operations: Experience supporting high-throughput systems in production environments and diagnosing complex issues across distributed systems. * Egoless Collaboration: A highly collaborative, feedback-receptive mindset focused on finding the best outcomes for our clients and business rather than defending personal preferences. * Communication: Excellent written and verbal communication skills, with the ability to build consensus and document technical designs clearly. Benefits * Highly competitive salary * Pension plan (match up to 5%) * Life insurance - three times annual salary * Competitive maternity (six months fully paid) and paternity leave (four weeks fully paid) * Shared parental leave (matched to our maternity leave for the same point in time) * 25 days holiday and bank holidays * Flexible working hours * Cycle-to-work scheme * Electric car scheme * Season ticket loan * Access to outstanding learning materials and courses * Sports and hobby clubs, subsidised by Thought Machine * All the latest tech you need * Start the day properly with fresh fruit and cereals * Huge range of healthy (and not-so-healthy) snacks, smoothies and drinks * A talented and experienced team as your colleagues * An environment where we encourage learning and progress * Two charity days a year * Weekly food pop-up We actively hire candidates who demonstrate technical excellence in their field and welcome people of all ages and backgrounds, providing everyone with equal access to professional development. You are encouraged to apply even if your experience doesn't accurately match the job description. We also encourage applications from those with different abilities, including candidates with ADHD, autism, dyslexia or dyspraxia. We actively hire candidates who demonstrate technical excellence in their field and welcome people of all ages and backgrounds, providing everyone with equal access to professional development. You are encouraged to apply even if your experience doesn't accurately match the job description. We also encourage applications from those with different abilities, including candidates with ADHD, autism, dyslexia or dyspraxia.

Thought Machine

Thought Machine's mission is bold – to properly and permanently rid the world's banks of legacy technology. To achieve this, we have developed the foundations of modern banking through core and payments technology which run natively in the cloud. What we are attempting is hard and means we need great people working together to build great technology. We have grown rapidly in the past few years – growing our team to more than 550 individuals across offices in London, New York, Singapore, Sydney and our newly established Engineering Hub in Lisbon. We have raised more than £500m in funding and our investors include Molten Ventures, Eurazeo, Intesa Sanpaolo, Temasek, Nyca Partners, JPMorgan Chase Strategic Investments, Standard Chartered Ventures, and more. We have created a culture that enables our team to produce the best work in the industry while ensuring we have fun along the way. We're regularly cited as having a fantastic workplace culture and have been recognised by Sifted magazine as having one of the highest Glassdoor ratings for a UK fintech company and the industry's most generous employee share package. Named one of the world's most innovative fintechs by Global Finance Magazine, we were also recognised by the Financial Times as one of Europe's fastest-growing companies for two consecutive years—and a UK Best Employer for 2026. As a Senior Software Engineer II, you operate with a wide sphere of influence. You will own complex, highly ambiguous technical challenges end-to-end, handling unexpected hurdles independently and gracefully. Your role goes beyond individual team delivery; you will drive systemic, organizational change and shape the long-term technical direction of our platforms. You will actively drive our engineering and company principles by aligning with our broader codebase, architecture, objectives, and goals, while acting as a crucial link between senior leadership, external stakeholders, and engineering teams. WHAT YOU’LL DO Technical Leadership * Design & Build: Create solutions to highly complex problems, utilising a deep understanding of the codebase and architecture, and lead the direction for future technical change. * Architecture & Standards: Utilise expertise to enable solutions to meet security, performance, cost, reliability, maintainability, and scalability requirements in a repeatable way and beyond existing capabilities, shaping the overall technical direction. Take part in defining standards and engineering practices for the entire company. Drive adoption of latest technologies, such as AI-tools, to scale developer velocity and code quality, keeping Thought Machine always ahead of the curve. * Technical Direction: Keep a pulse on industry-leading software trends and best practices, introducing new tools and processes that shape Thought Machine's technical roadmap. * Code Quality & Peer Review: Provide technical leadership and guidance to support others, ensuring their work items consider broader impact, long-term outcomes, and strategic direction end-to-end. * Operational Excellence: Investigate complex issues spanning across services in non-local or production environments (including across environments, clusters, and products), and possess a deep understanding to drive improvements to operational and production support processes. * Hiring: Lead technical interviews to actively evaluate the capability of Subject Matter Experts (SMEs) and leadership roles.. Product & Delivery * End-to-End Ownership: Own the solution to work items of undefined scope and high complexity end-to-end, handling unexpected complexity gracefully and independently. Drive delivery requiring effective and timely stakeholder management across larger milestones, which can potentially span multiple units or departments. * Product Vision: Utilise a deep understanding of the product to envision and contribute to future solutions, plans, and approaches. Drive the direction and actively contribute to the product strategy, vision, and long-term roadmap. Collaboration & Mentorship * Strategic Communication: Communicate seamlessly with stakeholders at all levels, managing leadership expectations while preserving the agility and focus of engineering teams. Build consensus, and enable solutions to complex, changing requirements * Team Growth: Inspire and empower others by example and through your guidance, knowledge sharing, and idea creation. Understand the capabilities and expertise of others to enable effective delegation and personal growth. Empower, inspire, and delegate effectively to senior engineers, fostering an environment of technical excellence and continuous growth. WHAT WE’RE LOOKING FOR * Technical Expertise and Leadership: Deep expertise in modern backend languages (ideally Go/Python) and large-scale, cloud-native systems. A proven technical leader who champions industry best practices, mentors peers, and drives the delivery of solutions to highly complex problems. * Problem Solving: A proven ability to solve highly complex problems of undefined scope, utilising your expertise for decision-making that actively influences the strategic direction of the department. * Production Operations: Extensive experience investigating complex issues across multiple environments, clusters, and products, with a demonstrated ability to drive systemic improvements to operational and production support processes. * Egoless Collaboration: A visionary mindset that does not accept the status quo. You are receptive to new ideas, able to see how different approaches can be combined advantageously, and focused on finding solutions that improve company and client outcomes. * Communication: Exceptional communication skills with the capability to provide leadership across a variety of stakeholders, drive organisational change, and set the direction for how engineers operate with technical excellence. Benefits * Highly competitive salary * Pension plan (match up to 5%) * Life insurance - three times annual salary * Competitive maternity (six months fully paid) and paternity leave (four weeks fully paid) * Shared parental leave (matched to our maternity leave for the same point in time) * 25 days holiday and bank holidays * Flexible working hours * Cycle-to-work scheme * Electric car scheme * Season ticket loan * Access to outstanding learning materials and courses * Sports and hobby clubs, subsidised by Thought Machine * All the latest tech you need * Start the day properly with fresh fruit and cereals * Huge range of healthy (and not-so-healthy) snacks, smoothies and drinks * A talented and experienced team as your colleagues * An environment where we encourage learning and progress * Two charity days a year * Weekly food pop-up We actively hire candidates who demonstrate technical excellence in their field and welcome people of all ages and backgrounds, providing everyone with equal access to professional development. You are encouraged to apply even if your experience doesn't accurately match the job description. We also encourage applications from those with different abilities, including candidates with ADHD, autism, dyslexia or dyspraxia. We actively hire candidates who demonstrate technical excellence in their field and welcome people of all ages and backgrounds, providing everyone with equal access to professional development. You are encouraged to apply even if your experience doesn't accurately match the job description. We also encourage applications from those with different abilities, including candidates with ADHD, autism, dyslexia or dyspraxia.