Senior Fullstack Engineer

ABOUT HOOK We’re building the future of customer growth. At Hook, we use AI and Machine Learning to help businesses predict revenue with accuracy, drive customer loyalty, and capture massive value from their existing customers. We’re a Series A company who ranked 33 out of 100 on the Sifted https://sifted.eu/leaderboards/sifted-100-uk-ireland-2025 fastest growing startups and we have raised $multi-million in funding from some of the top investors in Europe and the US (e.g. Balderton Capital and Lightspeed) and have an enviable list of customers that we’re working with including some of the fastest growing companies in the world. We’re looking for ambitious people that want to be part of our meaningful vision of changing how businesses engage with their customers, and of building one of the world’s leading workplaces for great people along the way. Responsibilities As a Senior Software Engineer at Hook, you'll work across the stack (with a backend focus) to build products and platform capabilities that directly impact our customers. Your day-to-day will include: - Working closely with engineers, product managers and designers to design and deliver customer-facing features - Building clean, well-tested and maintainable software across our Python backend and React frontend - Owning significant areas of our architecture and driving technical improvements - Designing scalable APIs, services and data models - Reviewing code and mentoring other engineers through thoughtful, constructive feedback - Improving engineering practices, tooling and development workflows across the team - Monitoring, maintaining and improving the performance and reliability of our production systems - Integrating with third-party platforms and services to extend our product capabilities As we continue to grow, you'll have the opportunity to take ownership of increasingly complex technical challenges and help shape both our product and engineering organisation. Requirements We're looking for an ambitious, collaborative engineer who enjoys solving difficult problems and wants to make a meaningful impact in a fast-growing company. You'll ideally have: - Experience building production software across both frontend and backend technologies (backend-focused) - Strong experience with Python and frameworks such as FastAPI, Django or Flask - Experience designing, building and operating software in production environments - Experience working with APIs and integrating third-party services - Strong communication skills and the ability to collaborate effectively across technical and non-technical teams - A pragmatic approach to problem-solving and a passion for writing high-quality software Desirable - Experience with cloud platforms such as AWS - Experience working with AI-powered products, machine learning systems or data-intensive applications - Experience designing scalable distributed systems Salary: £85,000-£105,000 (depending on experience) BENEFITS 🏖️ 27 days holiday (option to buy and sell holiday) + bank holidays 📈 Generous stock options 🏥 Private health insurance so you can get the best care you need 🧘 Flexible monthly wellness allowance that you can use monthly on things like gyms, yoga, mental health & healthy food 📚 Annual learning & development budget for every employee 🏢 Flexible working - we’ll all come together three days a week but otherwise you can work from home or come into our awesome office in Liverpool Street 💻 The best equipment for everyone to work with Our founder and team are incredibly passionate about creating a company culture that is diverse, inclusive, productive and enjoyable for all our colleagues. As part of a growing start-up team, we expect a lot from you and will work hard to make sure you have everything you need to be at your best.