Senior Full-Stack Software Engineer

Senior Full-Stack Engineer at PAIR (www.pairnow.ai) £80-120k + £53k equity, Hybrid (1 day/week London) Who We Are PAIR is a fast-growing AI adoption startup on a mission to help professionals and teams harness AI to do their best work. Our platform delivers personalised, AI-powered learning experiences and adoption support that help organisations rapidly harness AI at scale. We've already achieved: 30,000+ usersMajor enterprise deployments live today with the likes of the Ministry of Justice, you.com and PWCOver £1.8M ARRBacking from top-tier UK investors including Seedcamp, Venrex, Tom Hulme (Google Ventures) & Steve Garnett (ex-Chairman EMEA, Salesforce)US Expansion We're a small, high-calibre team that ships fast. Engineers here have a direct and visible impact on the product, users, and company trajectory. If you want meaningful ownership and an environment that values great engineering, you'll thrive. You'll be joining shortly after our Seed round, at a point where the core product is proven and live with enterprise customers, with huge scope to shape product, architecture, standards and technical direction as we take the platform to the next level. The Role We're hiring a Senior Full-Stack Engineer to help lead the development of our product platform across frontend and backend. You'll be responsible for building high-quality end-to-end product features while raising the bar for how we design, build and ship reliable software across the stack. This is a hands-on senior engineering role: you'll write production code, own key technical decisions, work closely with product and design, and mentor other engineers, without people management responsibilities. You'll: Build end-to-end product features, transforming how organisations adopt AISet standards for full-stack quality, testing, maintainability and technical designWork closely with the CTO, Director of Engineering, product and design to translate customer needs into robust, user-facing functionalityMake pragmatic technical decisions across frontend architecture, API design, data modelling and integrationsImprove the quality, usability, performance and reliability of the existing platform as usage growsOwn the full-stack role of key product areas, connecting AI-powered flows, learning content, authentication, core platform capabilities and user experience Our Stack Frontend: Vue 3, TypeScript Backend: Python, FastAPI, Postgres Cloud: Azure as primary (plus a small number of services on GCP) Infra & DevOps: Terraform, GitHub Actions, OpenTelemetry You don't need to know this exact stack, but you should be very comfortable working across a modern web application and able to make sound technical decisions across both frontend and backend systems in production. What We're Looking For Must-have experience Strong track record as a senior engineer building production web platforms across frontend and backendStrong experience with at least one modern frontend framework (Vue, React or Angular)Deep experience building APIs, backend services and data-driven product features in a modern language (Python preferred, but strong experience elsewhere is acceptable)Solid experience working with relational databasesComfort being the go-to person for technical decisions and trade-offs across a product areaComfort working closely with product and design to shape practical, user-centred solutionsProven skills harnessing AI-native ways of working to ship quickly without sacrificing qualityNice to have Vue and TypeScript experiencePython + FastAPI experienceExperience with multi-tenant SaaS systemsFamiliarity with cloud platforms (Azure, AWS or GCP)Experience working in a startup or small product team Why Join PAIR? Real impact: You'll help shape the product platform that enterprise customers rely on to stay relevant in the age of AI. Ownership: This is not a narrow role: you'll have real technical authority and responsibility across the stack. Work closely with the product: You'll collaborate directly with product and design and see how your work impacts customers. A-player environment: We hire carefully. You'll work with thoughtful, driven engineers who care about their craft. AI-native organisation: We practice what we preach and invest the time to make sure that we are harnessing AI across our business as our competitive advantage. Backed by top investors: Strong financial footing and backing from some of the best with meaningful revenue traction. Mission: Help people and organisations use AI confidently, not fear it Compensation & Working Setup Salary: £80-120k (experience dependent)Equity: £53k at current market value, vested over four yearsHybrid: 1 day/week in our central London office (Tuesdays)7 company-wide Anchor Weeks (in-person Mon-Thu) each year for deep collaboration25 days holiday + public holidaysRight to work: We can sponsor visas for exceptional candidates; applicants normally have UK work rights Hiring Process We keep the process simple and respectful of your time. Application form - basic details, skills matrix and a short case-study question. Apply here.30 minute introductory Teams call to talk about PAIR, the role, and how you might fit into itTechnical interview (remote) - a practical exercise to see your hands-on coding experienceFinal stage - meet the team in person, take on a system design challenge, and talk about how you'd help us scale PAIR over the next 12-24 months