Full Stack Engineer

About this role

👶 About Junior Junior is building the AI operating system for investment research. Our software helps private equity firms, consultants and financial institutions complete high-stakes research workflows dramatically faster - from diligence and memo writing to market mapping, research synthesis and strategic analysis. We’re trusted by several of the world’s top private equity firms, Big Four consultancies and leading financial institutions.

Bootstrapped and profitable ~£20M+ in revenue, after growing 10x last year 60+ people across the company 20-person engineering team, doubling to 40 this year Core stack: TypeScript, Next.js and PostgreSQL You’d be joining early enough to shape the product, engineering culture and company, but with enough traction that everything you build lands immediately in front of demanding, paying customers. 💡 The role You’ll own features end to end - across the frontend, backend and data layer - and ship on a weekly cadence, not a quarterly one.

You’ll: Ship quickly, then ship again Design and build entirely new ways of working with computers Work on groundbreaking projects involving LLMs Speak directly with the clients using what you build Use those conversations to shape product decisions Help define Junior’s engineering culture as the team doubles 🔧 Sample projects Build frontier products capable of ingesting new types of research inputs Build an extremely low-latency, voice-to-voice survey tool that autonomously conducts high volumes of research Build a mobile app from scratch in three weeks Create segmented knowledge graphs using unstructured-to-structured data transformations Build an AI-native CRM with deep links into that knowledge graph 🔥 About you You have 3+ years of engineering experience - we care about demonstrated competence, not pedigree You’re genuinely strong in TypeScript, Next.js and PostgreSQL, not merely familiar with them You can build a polished React/Next.js interface or work through a difficult TypeScript problem live and quickly, without relying on Copilot You have solid foundations in data structures, system design and PostgreSQL You’re high-agency and product-minded You’ve owned projects end to end, argued for what should be built - not only how - and shipped without being handed a detailed specification You communicate clearly and want a client-facing role You’re based in London, or already committed to relocating, and excited to work with the team in person in Farringdon You feel like you’re never building fast enough Bonus : you’ve built and designed AI-powered products 🧭 Interview process The process moves in days, not months: Introductory call : background, motivation and mutual fit Live technical screen (30-mins ): solving a TypeScript problem live in an IDE with one of our engineers.