Founding CTO / Head of Engineering - AI Defence Tech Startup

This is a job that Jill, our AI Recruiter, is recruiting for on behalf of one of our customers.

She will pick the best candidates from Jack's network.

The next step is to speak to Jack.

Job Title

CTO / Head of Engineering

Salary

Not Disclosed

Company Description

Pre-seed AI defence tech startup

Job Description

As the founding CTO of this pre-seed AI defence tech startup, you will build the technical foundation from zero. You will architect multi-agent systems to simulate information warfare and cognitive threats for EU government institutions. This is a hands-on leadership role combining high-level strategy with deep model development and team building.

Location

Looking to advance your Development & Programming career with relocation support? Explore Development & Programming Jobs with Relocation Packages that include comprehensive packages to help you move and settle in your new role.

London, UK

Why this role is remarkable

• Mission-driven work at the intersection of AI and national security, tackling the defining global challenge of cognitive threats.
• Founding-stage opportunity at a pre-seed startup backed by the urgent demand for European defence sovereignty and resilience.
• True co-founder autonomy to shape the technical architecture, engineering culture, and product direction from day one.
  
  

What You Will Do

• Architect and build multi-agent systems for population-level cognitive impact modelling and sophisticated threat simulation.
• Lead hands-on development including training and fine-tuning LLMs while managing complex data architectures for government clients.
• Recruit and lead the initial engineering team while establishing robust security and compliance standards for defence-grade technology.
  
  

  Discover our full range of relocation jobs with comprehensive support packages to help you relocate and settle in your new location.

The ideal candidate

• Proven track record as a CTO or technical founder at an early-stage startup, ideally having scaled through growth rounds.
• Deep technical expertise in AI/ML, specifically with hands-on experience training or fine-tuning LLMs and complex agent frameworks.
• Based in London (or willing to relocate) with a strong desire to build mission-critical technology from the ground up.
  
  

Who are Jack & Jill?

Ok, I'll go first. I'm Jack, an AI that gets to know you on a quick call, learning what you're great at and what you want from your career. Then I help you land your dream job by finding unmissable opportunities as they come up, supporting you with applications, interview prep, and moral support.

And I'm Jill, an AI Recruiter who talks to companies to understand who they're looking to hire. Then I recruit from Jack's network, making an introduction when I spot an excellent candidate.

How does this work?

• Jack's an AI agent for job searching and career coaching. He works for you.
• Jill is the AI recruiter working for the company. She recruits from Jack's network.
• If it's a match and the company wants to meet you, they'll make the intro. In the meantime, if you'd like, Jack will send you excellent alternatives.
  
  

We never post fake jobs

This isn't a trick. This is an open role that Jill is currently recruiting for from Jack's network.

Sometimes Jill's clients ask her to anonymize their jobs when she advertises them, which means she can't share all the details in the job description.

We appreciate this can make them look a bit suspect, but there isn't much we can do about it.

Give Jack a spin! You could land this role. If not, most people find him incredibly helpful with their job search, and we're giving his services away for free.