Founding Engineer

ByteSearch; Greater London; On-site; GBP 80,000 - 120,000; Full time

Job summary

ByteSearch is seeking a Founding Engineer in Greater London to take ownership of their core AI platform from day one. You will design and build backend systems, ensuring scalability and integration with external platforms. Ideal candidates have experience in AI/LLM systems and enjoy fast-paced, early-stage environments where they can have a genuine impact on product direction. This role offers significant autonomy and responsibility, shaping the technical landscape from the ground up.

Qualifications

• Experience building and shipping AI / LLM-powered systems.
• Solid understanding of scalable system design and distributed architectures.
• Comfortable operating in a fast-moving, early-stage environment.

Responsibilities

• Design and build core backend systems powering AI-driven workflows.
• Own architecture across APIs, data pipelines, and distributed systems.
• Integrate with external platforms and third-party systems.

Skills

Building and shipping AI / LLM powered systems

Scalable system design

Distributed architectures

Data pipelines

Working in a fast-moving environment

Taking ownership from idea to production

Job description

We’re working with an early-stage company building a next-generation AI platform to transform a large, traditional industry.

They’re looking for a Founding Engineer to take ownership of the core platform from day one and help scale it into a category-defining product.

The opportunity:

This is a true 0 to 1 role.

You’ll be responsible for architecting and building the core system that powers the product, working directly with the founders and shaping both the technical direction and product itself.

If you’re someone who enjoys high ownership, fast pace, and building from scratch, this is one of those rare roles where you can have a genuine impact.

What you’ll be doing:

• Designing and building the core backend systems powering AI-driven workflows
• Owning architecture across APIs, data pipelines and distributed systems
• Working on LLM orchestration and retrieval systems in production
• Integrating with external platforms and third-party systems
• Contributing across the stack where needed

What they’re looking for:

• Experience building and shipping AI / LLM-powered systems
• Solid understanding of scalable system design and distributed architectures
• Experience with data pipelines, retrieval systems or similar
• Comfortable operating in a fast-moving, early-stage environment
• Ability to take full ownership from idea to production

Nice to have:

• Experience with real-time systems or communication platforms
• Exposure to voice, messaging or streaming systems
• Previous startup or founding engineer experience
• Early-stage, high-growth environment
• Direct impact on product and technical direction
• Large, complex market with significant upside
• Strong ownership and autonomy from day one