Duffel
London (Hybrid - 2 days onsite) Permanent Start ASAP Experience: Senior Create the future of travel with us Whether it's to visit the people closest to us, starting an exciting adventure, or a career-defining business trip, travel is an essential part of our lives. Yet we've all experienced the aches and pains of getting to our destination. Today, more than 4 billion airline passengers rely on technology that hasn't kept up with the expectations of the modern connected traveller. That's why we've started to rebuild the infrastructure that underpins the travel industry. We're on a mission to unravel travel - simplifying systems and building the tools that will make the future of travel effortless. We were part of Y Combinator S18's cohort and we are backed by Benchmark, Blossom, Index Ventures and Kima Ventures. Our team in London is growing and we're looking for talented people to join us on our journey. AI at Duffel Travel is one of the most demanding domains for AI. A single trip can span multiple airlines, hotels, payments, policies, and time zones - and when something goes wrong, travellers need answers fast. We're building a chat-based AI assistant that helps travellers manage trips booked through Duffel: changing a flight, understanding a fare rule, recovering from a disruption, getting a receipt - all the things that today mean a phone call or a long wait. Behind that experience sits a platform: the orchestration, retrieval, memory, and evaluation systems that let agents reason reliably over real bookings, real money, and real policies. As a senior AI Engineer, you'll help build that platform from the ground up and set the technical direction for how we build agents at Duffel. What you'll get to do Design, ship, and own production-grade AI agents end-to-end - from intent through to taking action against Duffel's APIs - and define the agent development lifecycle the rest of the team will follow. Build the core platform that powers our agents: the orchestration engine, runtime, and primitives that define how agents reason, take actions, and interact with users - keeping them steerable and verifiable while staying conversational and adaptive. Make agents trustworthy. Build the retrieval and grounding systems that ensure responses are accurate, and the evaluation frameworks that let us measure and improve agent quality deliberately rather than vibes-first. Lay the foundations for memory and personalisation: long term agent memory, reusable customer data primitives, and the optimisation loops that let agents personalise interactions and demonstrably lift business outcomes. What we're looking for in you Significant experience shipping AI agents and LLM systems into production, with strong opinions on the modern toolkit - eval frameworks, agent orchestration, RAG pipelines, prompt engineering - and the tradeoffs between them. A track record of taking ambiguous problems from zero to one, raising the bar for the engineers around you, and shaping technical direction across teams. A strong general engineering foundation. We care more about your ability to design good systems than about any specific language or framework - you'll work across our stack as needed (Elixir on the backend, TypeScript on the frontend). Big picture thinking - you can make tradeoffs on technical work streams against business impact, and know when to ship something rough to learn from versus when to invest. Fantastic communication skills. You're able to articulate what you're working on and why to the team in a clear and structured way. You thrive in a collaborative environment. You believe in your own methods but keep an open mind, taking suggestions and feedback onboard as well. Bonus if you have experience in travel, flights, hotels or cars. Location We are based in Shoreditch, London and have a hybrid work-from-home policy and require everyone to come to our office on Tuesdays and Thursdays. Why Join Duffel? We're a growth-focused team that values open communication, diverse perspectives, and true ownership. We want you to feel empowered in your role, which is why every permanent employee becomes a company shareholder. Benefits Duffel Travel Allowance: We subsidise your wanderlust. Work From Anywhere (60 days): Your office, your rules. Sabbaticals: Long term loyalty, long term breaks. Flexible Bank Holidays: Swap holidays to suit your schedule. Level Up & Give Back Study Days: Get paid to learn. Volunteering Day: One day a year to save the world. Electric Car & Cycle Schemes: Eco friendly rides, tax free prices. The Essentials, Upgraded Family Leave (maternity, paternity and adoption): Big support for life's biggest moments, 26 weeks fully paid. Pensions & Loans: Future proofing and interest free commuting. Eye Tests: Keeping your vision and your style sharp. We are an equal opportunities employer. We believe that the key to our success is employing a diverse team, that's why recruitment decisions are only based on your experience and skills. We value your ability to problem solve and build amazing things so we welcome applications for everyone - regardless of age, sex, disability, sexual orientation, race, religion or belief.
London (Hybrid - 2 days onsite) Permanent Start ASAP Experience: Senior Create the future of travel with us Whether it's to visit the people closest to us, starting an exciting adventure, or a career-defining business trip, travel is an essential part of our lives. Yet we've all experienced the aches and pains of getting to our destination. Today, more than 4 billion airline passengers rely on technology that hasn't kept up with the expectations of the modern connected traveller. That's why we've started to rebuild the infrastructure that underpins the travel industry. We're on a mission to unravel travel - simplifying systems and building the tools that will make the future of travel effortless. We were part of Y Combinator S18's cohort and we are backed by Benchmark, Blossom, Index Ventures and Kima Ventures. Our team in London is growing and we're looking for talented people to join us on our journey. AI at Duffel Travel is one of the most demanding domains for AI. A single trip can span multiple airlines, hotels, payments, policies, and time zones - and when something goes wrong, travellers need answers fast. We're building a chat-based AI assistant that helps travellers manage trips booked through Duffel: changing a flight, understanding a fare rule, recovering from a disruption, getting a receipt - all the things that today mean a phone call or a long wait. Behind that experience sits a platform: the orchestration, retrieval, memory, and evaluation systems that let agents reason reliably over real bookings, real money, and real policies. As a senior AI Engineer, you'll help build that platform from the ground up and set the technical direction for how we build agents at Duffel. What you'll get to do Design, ship, and own production-grade AI agents end-to-end - from intent through to taking action against Duffel's APIs - and define the agent development lifecycle the rest of the team will follow. Build the core platform that powers our agents: the orchestration engine, runtime, and primitives that define how agents reason, take actions, and interact with users - keeping them steerable and verifiable while staying conversational and adaptive. Make agents trustworthy. Build the retrieval and grounding systems that ensure responses are accurate, and the evaluation frameworks that let us measure and improve agent quality deliberately rather than vibes-first. Lay the foundations for memory and personalisation: long term agent memory, reusable customer data primitives, and the optimisation loops that let agents personalise interactions and demonstrably lift business outcomes. What we're looking for in you Significant experience shipping AI agents and LLM systems into production, with strong opinions on the modern toolkit - eval frameworks, agent orchestration, RAG pipelines, prompt engineering - and the tradeoffs between them. A track record of taking ambiguous problems from zero to one, raising the bar for the engineers around you, and shaping technical direction across teams. A strong general engineering foundation. We care more about your ability to design good systems than about any specific language or framework - you'll work across our stack as needed (Elixir on the backend, TypeScript on the frontend). Big picture thinking - you can make tradeoffs on technical work streams against business impact, and know when to ship something rough to learn from versus when to invest. Fantastic communication skills. You're able to articulate what you're working on and why to the team in a clear and structured way. You thrive in a collaborative environment. You believe in your own methods but keep an open mind, taking suggestions and feedback onboard as well. Bonus if you have experience in travel, flights, hotels or cars. Location We are based in Shoreditch, London and have a hybrid work-from-home policy and require everyone to come to our office on Tuesdays and Thursdays. Why Join Duffel? We're a growth-focused team that values open communication, diverse perspectives, and true ownership. We want you to feel empowered in your role, which is why every permanent employee becomes a company shareholder. Benefits Duffel Travel Allowance: We subsidise your wanderlust. Work From Anywhere (60 days): Your office, your rules. Sabbaticals: Long term loyalty, long term breaks. Flexible Bank Holidays: Swap holidays to suit your schedule. Level Up & Give Back Study Days: Get paid to learn. Volunteering Day: One day a year to save the world. Electric Car & Cycle Schemes: Eco friendly rides, tax free prices. The Essentials, Upgraded Family Leave (maternity, paternity and adoption): Big support for life's biggest moments, 26 weeks fully paid. Pensions & Loans: Future proofing and interest free commuting. Eye Tests: Keeping your vision and your style sharp. We are an equal opportunities employer. We believe that the key to our success is employing a diverse team, that's why recruitment decisions are only based on your experience and skills. We value your ability to problem solve and build amazing things so we welcome applications for everyone - regardless of age, sex, disability, sexual orientation, race, religion or belief.
Duffel
Software Engineer London Full-time Hybrid Shoreditch/Liverpool Street Create the Future of Travel With Us Whether it's visiting the people closest to us, starting an exciting adventure, or a career-defining business trip, travel is essential. Yet we've all experienced the aches and pains of getting to our destination. More than 4 billion airline passengers rely on technology that hasn't kept up with modern expectations. That's why we're rebuilding the infrastructure that underpins the travel industry - simplifying systems and building tools that will make the future of travel effortless. We were part of Y Combinator S18's cohort and we're backed by Benchmark, Blossom, Index Ventures, and Kima Ventures - a fantastic set of investors that has helped build some of the world's largest companies. Our London team is growing, and we're looking for talented people to join us on our journey. Engineering at Duffel We're building tools to simplify travel distribution, search, and booking through one seamless API. The technical challenge? Design a beautiful API, then integrate it with hundreds of travel providers - each with different systems and requirements - whilst delivering a fantastic developer experience. We work with Elixir, Phoenix, Kubernetes, and Google Cloud Platform, but we value strong engineering fundamentals over specific tech experience. Responsibilities Work on the core API powering millions of travel bookings, designing beautiful APIs and creating great developer experiences. Define engineering standards and processes, and build integration solutions with hundreds of travel providers. Qualifications Passionate about designing beautiful APIs and creating great developer experiences High bar for code quality and API design Opinionated about good engineering standards and processes, as we define ours at Duffel Think big picture - making trade offs between technical work and business impact Communicate clearly, articulating what you're working on and why in a structured way Collaborate well - believe in your methods but stay open to feedback and suggestions Bonus Experience in travel, flights, hotels, or cars. Benefits Competitive salary + equity (you'll own part of Duffel) Work from anywhere policy Duffel travel allowance (use what we build) Matched parental leave Sabbatical programme (3 months full pay) Visa sponsorship available Office in Shoreditch + regular team socials Why Now Matters You'll work on the core API powering millions of travel bookings. Early stage role = outsized impact on how we build and scale.
Software Engineer London Full-time Hybrid Shoreditch/Liverpool Street Create the Future of Travel With Us Whether it's visiting the people closest to us, starting an exciting adventure, or a career-defining business trip, travel is essential. Yet we've all experienced the aches and pains of getting to our destination. More than 4 billion airline passengers rely on technology that hasn't kept up with modern expectations. That's why we're rebuilding the infrastructure that underpins the travel industry - simplifying systems and building tools that will make the future of travel effortless. We were part of Y Combinator S18's cohort and we're backed by Benchmark, Blossom, Index Ventures, and Kima Ventures - a fantastic set of investors that has helped build some of the world's largest companies. Our London team is growing, and we're looking for talented people to join us on our journey. Engineering at Duffel We're building tools to simplify travel distribution, search, and booking through one seamless API. The technical challenge? Design a beautiful API, then integrate it with hundreds of travel providers - each with different systems and requirements - whilst delivering a fantastic developer experience. We work with Elixir, Phoenix, Kubernetes, and Google Cloud Platform, but we value strong engineering fundamentals over specific tech experience. Responsibilities Work on the core API powering millions of travel bookings, designing beautiful APIs and creating great developer experiences. Define engineering standards and processes, and build integration solutions with hundreds of travel providers. Qualifications Passionate about designing beautiful APIs and creating great developer experiences High bar for code quality and API design Opinionated about good engineering standards and processes, as we define ours at Duffel Think big picture - making trade offs between technical work and business impact Communicate clearly, articulating what you're working on and why in a structured way Collaborate well - believe in your methods but stay open to feedback and suggestions Bonus Experience in travel, flights, hotels, or cars. Benefits Competitive salary + equity (you'll own part of Duffel) Work from anywhere policy Duffel travel allowance (use what we build) Matched parental leave Sabbatical programme (3 months full pay) Visa sponsorship available Office in Shoreditch + regular team socials Why Now Matters You'll work on the core API powering millions of travel bookings. Early stage role = outsized impact on how we build and scale.