Founding Engineer

Founding Engineer | London (Hybrid) | £200,000 + Equity

At Dex, we're helping build the early, elite teams for London's most ambitious companies. We are partnered with exceptional, 'breakout' AI startups, some you'll know, some in stealth, all with world-class backing (YC, A16Z, etc.) and truly game-changing missions.

The Opportunity

This is not a typical \"big team\" leadership role. We are looking for proven technical leaders, CTOs, ex-founders, and top-tier Principal Engineers, who are still deeply technical and want to keep building!

Our partners are scaling fast. They need leaders who can own and scale core product, infrastructure, and help lead strategy, whilst also writing the code to make it happen. You will be a force multiplier, defining the \"how\" for a small, world-class team and solving the hardest technical challenges.

What You'll Work On

• Define and own the technical strategy for core, business-critical AI products.
• Lead the architecture and build the next-generation of scalable, high-performance systems that can handle millions of users and complex AI workloads.
• Solve the hardest problems in applied AI: from model fine-tuning and novel RAG techniques to high-throughput, low-latency data infrastructure.

What You'll Have

• A proven track record: You have been a CTO, Founder (especially from YC/EF), or a Principal/Staff Engineer at a successful, high-growth startup.
• Expert, \"hands-on\" skills in TypeScript and building complex distributed systems.
• Deep expertise in architecting and deploying complex AI/ML systems (LLMs, RAG, data platforms).
• You've likely done this before, and are raring to do it again, faster, better, and with a world-class team.

If you're interested, apply here to head to the website, where you can sign up and speak to us. After your call, you'll be sent the full details, as well as be matched with other teams that we think you'll love.