Join a high-velocity team building the "Duolingo for everything." As a Principal Product Engineer, you will own major product slices, reporting directly to the CEO. You'll build delightful, gamified learning experiences for over 1 million monthly users, iterating daily based on real-time session replays and metrics in a flat, senior-heavy engineering culture.
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Principal Product Engineer at Gizmo
Gizmo.ai is reinventing learning through gamification and AI, and they’re looking for a Principal Product Engineer to join their elite Shoreditch-based team. With 1 million monthly active users and a fresh $22M Series A, this is a rare chance to work alongside ex-founders and CTOs in a flat, high-velocity environment. If you have 8+ years of experience and want to own major product features from ideation to daily production deployments, this is the highest-impact IC role in London right now.
About this role
Role overview
About the company
Gizmo
Software
Gizmo.ai - Series A AI EdTech startup
What you'll do
What you will do
- Lead the end-to-end execution of user-facing features, focusing on high-performance React interactions and seamless mobile/web experiences.
- Collaborate directly with the CEO and design teams to transform complex Figma concepts into functional, high-quality code that solves real user problems.
- Maintain full-stack ownership by contributing to PostgreSQL back-end logic and APIs while ensuring the frontend remains world-class and intuitive.
Who you are
Who this is a fit for
- Expert-level proficiency in React, TypeScript, and Tailwind with 8-20 years of software engineering experience in fast-paced environments.
- Proven "maker" mindset, ideally as a former founder or early-stage startup engineer comfortable with 80/20 frontend-to-backend splits.
- Quantitative background with a degree from a top-tier university and a relentless focus on moving metrics through rapid product iteration.
Why this role
Why this role is remarkable
- Work at one of the UK’s fastest-growing startups with 1M+ MAUs and $4M ARR, recently backed by $22M in Series A funding to reach 1 billion learners.
- Join a deliberately small, elite engineering squad where every member operates at a Staff or Principal level, including ex-CTOs and former founders.
- High-autonomy environment where you ship to production daily and see the immediate impact of your work on a global user base within hours.
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