Location: London or New York
Package: Competitive cash salary plus meaningful founder-level equity
Reporting to: Founder/CEO
Search led by: Exec Capital
The Opportunity
Our client is a well-established, high-reach media group building a new AI venture on top of a large existing audience base. The product is a synthetic audience simulation platform: a system that lets brands test products, campaigns and strategies against simulated populations of consumers before committing to them in the real world.
This is a genuine founding-level appointment. The successful candidate will be employee one on the technical side, building the engineering team, the architecture and the platform from the ground up. It is a rare opportunity to take a well-funded, well-connected AI venture from zero to one, with real equity upside and the backing of an established media business with a substantial existing audience.
The Role
As Founding CTO, you will own the technical vision and build the team and platform capable of simulating populations ranging from millions up to a billion lightweight agents, returning results in minutes rather than days. You will work closely with the founder to translate a bold product vision into a working, credible, commercially defensible platform — one where simulated outcomes can be shown, through rigorous calibration and back-testing, to track real-world outcomes.
You will be responsible for every major technical decision in the venture's early life: architecture, infrastructure, hiring, and the technical roadmap. This is a build-from-scratch mandate, not a role inheriting an existing codebase or team.
What We're Looking For
- Agent-based simulation or synthetic audience/persona systems — hands-on experience designing or scaling systems that model human behaviour computationally, whether from ad tech, market research technology, gaming, computational social science or an AI lab
- Large-scale distributed systems — a track record architecting high-throughput, massively parallel workloads capable of scaling to populations in the hundreds of millions or billions
- LLM and generative AI in production — practical experience deploying foundation models, fine-tuning, and/or agentic frameworks in a live commercial product, not just prototypes or research settings
- Behavioural or consumer data pipelines — experience building the data infrastructure that turns messy first-party behavioural signal and licensed demographic data into model-ready training input, with privacy and consent architecture properly handled
- Simulation validity — a genuine understanding of calibration and back-testing methodology, and what it takes to prove simulated outcomes track real-world outcomes
- Zero-to-one leadership — prior experience as a founding engineer, CTO, or technical lead of a new platform, with the credibility to hire and lead a founding engineering team spanning ML and data engineering
We expect the strongest applicants to come from AI labs, simulation or ad-tech platforms, large-scale personalisation or recommendation systems, or computational modelling teams — people who see the challenge of simulating a billion agents as an exciting problem to solve rather than a daunting one. Very few candidates will bring deep expertise across every point above; what matters most is genuine strength across several of these areas, the judgement to hire well against the gaps, and the conviction to lead a technical build of this ambition from day one.
Why Apply
- A true founding-level role with meaningful equity, not a later-stage technical leadership hire
- Backing and distribution from an established, high-reach media business
- A technically ambitious, category-defining product with genuine commercial pull from brand and agency clients
- Direct partnership with the founder in shaping both the product and the company from the outset
- Flexibility to be based in London or New York
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