Full-Stack Engineer

Full-Stack Engineer

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 already have strong traction: 

• 15,000+ users 

• Enterprise deployments with organisations including PwC, the Ministry of Justice, you.com and The MTC 

• £1.8M+ ARR run-rate 

• Backing from investors including Seedcamp, Venrex, Tom Hulme (Google Ventures) and Steve Garnett (ex-Chairman EMEA, Salesforce)  

Our core product is proven and live with enterprise customers, and we're taking the platform to its next stage after our Seed round. You'll help improve its quality, usability, performance and reliability as usage grows, while raising our standards for how we design, build and ship.

You'll start by owning key product areas across frontend and backend, with scope to shape architecture, engineering standards and technical direction as we grow. This role requires strong individual contributors able to delivery technical excellence consistently.

What you'll own

• End-to-end product delivery: Build and own features across frontend, APIs, data and integrations, connecting AI-powered flows, learning content, authentication and the core platform into a coherent user experience.

• Engineering quality and technical implementation: Make pragmatic decisions across frontend and backend architecture, API design and data modelling; set standards for testing, maintainability and technical design; improve performance and reliability as usage grows.

• Product partnership and technical contribution: Work with your pod, Engineering manager,  Product and Design to turn customer needs into robust functionality, and raise the quality of what we ship.

What we're looking for

We hire for aptitude, hunger and a bias to action over years of experience. This role works best for someone who wants to own a product area, set technical direction and still enjoy writing production code.

You'll bring evidence of:

• Building production web platforms across frontend and backend as a fullstack engineer.

• Strong experience with a modern frontend framework such as Vue, React or Angular.

• Deep experience with modern backend frameworks like FastAPI, backend services like Celery and data-driven features in a modern language. Python is preferred, but strong experience elsewhere is welcome.

• Working with relational databases and making sound technical decisions and trade-offs across a product area.

• Working closely with Product and Design to shape practical, user-centred solutions.

• Using AI-native ways of working to ship quickly without sacrificing quality.

• Curiosity about AI and how it changes the way organisations work - you don't need to be an expert when you join, but you'll want to form your own point of view quickly.

Useful but not essential:

• Vue and TypeScript; Python, FastAPI and Celery.

• Multi-tenant SaaS systems, cloud platforms such as Azure, AWS or GCP, and experience in a startup or small product team.

We know great candidates don't always tick every box. If the scope excites you and you think your experience could translate, we'd love to hear from you.

Our stack:
Vue 3 and TypeScript; Python, FastAPI, Celery and Postgres; Azure with a small number of GCP services; Terraform, GitHub Actions and OpenTelemetry. You don't need this exact stack, but should be comfortable across modern production frontend and backend systems.

• You'll work alongside thoughtful, driven engineers and partner directly with Product, Design, the Director of Engineering and CTO, with real ownership of a platform enterprise customers rely on.

• Equity: Everyone at PAIR is offered equity, because we want everyone to share in what we build together.

• Holiday: 25 days, plus bank holidays

• Learning: access to the best AI tools and PAIR's own masterclasses

• A path to grow your career: we're an early stage company that promotes from within. As we continue to scale, the opportunities to grow with us will only increase

• Regular social events: to celebrate the wins, unwind and and enjoy the journey together!

The fine print

• This role is hybrid, with 1 day per week in our central London office

• We also come together for 7 company-wide Anchor Weeks each year (in person, Monday to Thursday).

• Visa sponsorship is available for exceptional candidates; applicants normally have the right to work in the UK.

Inclusion and adjustments
We welcome applicants from all backgrounds. Every candidate for this role is assessed against the same published criteria, by interviewers using the same core questions. If you need any reasonable adjustments at any stage - a different format, more time, or flexible scheduling - just let us know.

About PAIR

At PAIR, ambitious people get real responsibility - and with it, the most meaningful work of their career.

PAIR is the AI adoption platform for enterprise. We help organisations turn their investment in tools like ChatGPT, Copilot and Claude into measurable business value. Our platform builds practical AI capability across the workforce, helps teams surface and scale their strongest agents and workflows, and gives leaders the visibility to make better decisions about performance, governance and AI investment.

We believe humans should remain the main characters. AI is an extraordinary tool, but the organisations that thrive will pair the best of human intelligence with the best of artificial intelligence. We're building the infrastructure for a future where AI elevates human potential rather than replacing it.

It’s working. More than 400 organisations and 40,000 users now use PAIR, including PwC, Healf and The Crown Estate. Our ARR grew 1,400% in 2025 and is on track to grow more than 5x this year. We’re backed by Seedcamp, Venrex, Tom Hulme of Google Ventures and Steve Garnett, former Chairman of Salesforce EMEA, and we’ve just opened our first international office in New York.

You'd be joining at a pivotal moment: small enough that your work is visible, and growing fast enough that new ground opens up constantly.