Cofounder (Engineering)

The Opportunity

We're building BIG – social identity for the agentic web. A structured, permissioned knowledge graph of who you are that any AI can understand, simulate, and interact with.

I'm a serial founder and experienced product geek looking for a highly talented technical cofounder to build this from zero. I've already raised the pre-seed, so our focus will be entirely on build/ship/learn/iterate. This is a true co-building role with significant equity and the chance to shape something genuinely new.

What You'll Build

• A beautiful, expressive identity builder that Gen Z actually wants to use
• An MCP server that makes user identities queryable by any AI
• Integrations that pull identity data from Spotify, LinkedIn, and beyond
• Permission systems that give users granular control over who sees what
• AI-assisted curation that helps users build their identity through conversation
• Discovery and social graph features as the network grows

What We're Looking For

Technical

• Strong frontend craft – you can build polished, highly interactive UIs with modern frameworks (React, Next.js, etc). Design sensibility matters.
• Backend competence – whatever stack works. You can build APIs, handle auth, manage data. Not precious about technology choices.
• AI/Agent experience – hands-on with agent orchestration, MCP, embeddings, integrations. You understand where AI is going and how to build for it.
• Infrastructure literacy – comfortable with GCP, AWS, or similar. Can ship and scale.
• Not a vibe coder – you actually understand what you're building, not just prompting your way through. LLMs are tools, not crutches. CS degree preferred.

Experience Level

Either senior engineering experience with a track record of shipping consumer products, OR a supremely talented middleweight who's been building things people actually use. Pedigree matters less than proof.

Who You Are

• Hands-on generalist – frontend, backend, infra, product thinking.
• Builder who ships fast – you have a bias toward action. You'd rather ship something imperfect than perfect something unshipped.
• Build in public energy – confident, opinionated, willing to share work early and learn from feedback.
• Product-obsessed – you care deeply about what users experience. Craft matters to you.
• AI-native – genuinely excited about agents, LLMs, and where this is all going. Not just following the hype.
• Super bullish on agentic opportunities – you see the same future we do and want to build the infrastructure for it.
• All-in mentality – this is a rapid, high stakes startup - not a 9-5.
• Courage – or madness, or audacity. Whatever you call the thing that makes someone try to build a consumer unicorn when the odds say don't.

The Package

• Equity: 10-20% – real founder-level stake. You're not joining, you're co-building.
• Salary: £70-100k – enough to live, not enough to get comfortable.

Location

Flexible. Based in London (preferred) but open to remote for the right person.

Why Now

MCP is becoming the standard for AI-to-tool communication. Agents are proliferating. But there's no good answer to the question: "How does an AI actually know who someone is?"

Right now, every AI has to start from scratch with every user. Your AI assistant doesn't know your AI coach. Your digital twin can't actually represent you because it doesn't know you.

BIG fixes this. One identity, queryable by any AI, controlled entirely by you.

If this sounds exciting, please reach out.