Founding Engineer

ByteSearch; Greater London; On-site; GBP 90,000 - 130,000; Full time

Job summary

ByteSearch is seeking a Founding Engineer in London to own and shape the core platform from day one, guiding both technical direction and product. This is a true 0→1 role with high ownership and the chance to set architecture and scale for a category-defining AI platform.

You’ll design and build the core backend systems powering AI-driven workflows, own APIs, data pipelines and distributed systems, and drive LLM orchestration in production while collaborating directly with founders.

Qualifications

• 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 → production

Responsibilities

• 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

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 an 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→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 → 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