Full-Stack Engineer (Backend focused) | AI Gamification Startup

Gizmo is an AI startup on a mission to make learning so easy that anyone can learn anything. We're building Duolingo for anything - a platform that uses gamification and social mechanics to make learning fun. With over 1 million monthly active users and $4M in annual recurring revenue, we’re already one of the fastest-growing startups in the UK. Backed by leading investors, we recently raised $16M in Series A funding to accelerate our vision of helping 1 billion people learn. Role Overview As a Fullstack Developer at Gizmo, you’ll report directly to the Founders and play a key role in shaping the product experience for our rapidly growing user base. While you'll be comfortable working across the full stack, your focus will be on delivering world-class backend experiences that make learning intuitive, playful and engaging. You’ll work closely with our wider engineering team to build, test and ship features that bring our vision to life. You’ll be joining a fast-paced, collaborative team during an exciting stage of growth, with plenty of opportunity to make a significant impact and grow alongside us as we scale. Key Responsibilities Build, maintain and scale backend services and APIs that support our learning platform across web and mobile. Collaborate with the wider engineering team and product designers to deliver features that are seamless, intelligent and impactful. Contribute across the full stack. While the backend will be your focus, you’ll be able to contribute to frontend codebases when needed. Integrate advanced features such as personalisation, gamification and spaced repetition into the platforms core experience. Own features end-to-end: from architectural design to development, deployment and iteration. Participate in code reviews, technical planning and team stand-ups helping us maintain a high engineering standard. Strong fullstack fundamentals with a backend focus and proven experience shipping complex features. You are skilled in Python, PostgreSQL and familiar with TypeScript. Preference (not essential) for proficiency in React and familiarity with tools like BigQuery, Pub/Sub, Celery, Redis or RabbitMQ. Clear communicator who can break down complexity and collaborate effectively. Driven by impact - you prioritise work that moves the needle. Self-starter with a maker mindset. We’re looking for ex-founders or individuals with start-up experience. You are a fast learner who’s not afraid of new challenges - you are ambitious and motivated to build something meaningful. Open-minded and feedback-oriented, always striving to learn and improve. Happy to work hard for a chance at building something great! Highly competitive salary. You'll own a piece of what you're building - equity included. Hybrid working model with 4 days in the London Liverpool Street office. The opportunity to become one of the earliest employees in one of the UK’s fastest-growing startups.