
Staff Product Engineer (AI Focus)
Early applicant
Hybrid
Employee
Full-Time
Senior Level
We’re hiring an experienced/staff-level Product Engineer (AI-focused) to build and scale the core intelligence behind Gizmo. Reporting to the CEO and Co-Founder, you’ll work across our TypeScript codebase to ship AI-powered features used daily by thousands of students, including study material generation, quizzes, automated marking and content ingestion. This is not an ML research role. It is a hands-on product engineering position focused on designing and improving production AI systems with real user impact. If you want to build AI that sits at the heart of a product and see your work make a tangible difference at scale, this role offers genuine impact.
Responsibilities
Building AI-Powered Product Features
- You will operate as a full product engineer, owning AI features end to end:
- Design and ship AI-driven user-facing features in our TypeScript stack
- Take ownership of AI features from idea through to production and iteration
- Collaborate closely with design and product to solve real learning problems with end to end AI solutions
- Write clean, maintainable, production-ready code
- Contribute to architectural decisions across backend and AI systems
- Improve the user experience around AI outputs, including feedback loops and refinement flows
Owning and Improving Production AI Systems
- You will take responsibility for AI systems that are already live and used daily.
- These include:
- Study material content generation
- Quiz question generation
- Automated marking and feedback
- Structured content ingestion pipelines
- You will:
- Optimise production AI pipelines
- Design and iterate on prompts, including agentic prompt engineering and multi-step workflows
- Build structured model pipelines rather than simple single-call integrations
- Integrate model improvements directly into our TypeScript backend
- Create novel AI-powered systems to solve new product challenges
- Prototype and productionise new model-driven capabilities
Designing Evaluation and Quality Frameworks
- You will:
- Define what great looks like across different AI use cases
- Design internal evaluation frameworks
- Develop clear metrics for quality, correctness and usefulness
- Evaluate multi-step and agentic workflows for robustness
- Run structured experiments to drive systematic improvement
- Build internal tooling to support iteration and experimentation
Ensuring Reliability at Scale
- You will:
- Monitor model behaviour and system health
- Handle API rate limits and third-party outages
- Improve resilience, retries and fallback logic
- Design robust model-calling infrastructure
- Ensure AI features remain stable and performant under scale
Requirements
- 8+ years of software engineering experience
- Strong expertise in TypeScript is preferred; however, we would also consider candidates with strong JavaScript experience
- Degree in Machine Learning, Artificial Intelligence, or a related quantitative discipline; alternatively, demonstrable hands-on experience evaluating AI models and prompts in a production environment
- Experience building and maintaining production systems
- Experience shipping user-facing product features
- Experience designing structured or agentic prompt workflows
- Ability to define and implement evaluation metrics for AI-driven features
- Clear communicator who can collaborate with technical and non-technical stakeholders
- Strong product instincts and a focus on impact
Nice to Have
- Previous start-up or founder experience
- Experience building internal tooling for experimentation and evaluation
Benefits
- Highly competitive salary
- You'll own a piece of what you're building - equity included
- Hybrid and flexible working model with 4 days in our Shoreditch, London office
- Private health insurance
- Enhanced parental leave
- The opportunity to become one of the earliest employees in one of the UK’s fastest-growing startups
About Gizmo
Gizmo is an AI startup on a mission to make learning so easy that anyone can learn anything. We're building a platform that uses gamification and social mechanics to make learning fun. With over 1.7 million monthly active users and $5M in annual recurring revenue, we’re already one of the fastest-growing startups in the UK. Backed by leading investors, we recently raised $22M in Series A funding to accelerate our vision of helping 1 billion people learn.
Skills
TypeScript
JavaScript
Machine learning
Artificial intelligence
Prompt engineering
Backend





