Founding AI Engineer

X4 Engineering; Greater London; On-site; GBP 70,000 - 120,000; Full time

Benefits offered by this job

Equity

Annual bonus

Lunch & dinner

Team meals

Relocation visa support

Job summary

X4 Engineering in London is seeking exceptional AI/Software Engineers to join an early-stage AI tech company scaling rapidly. You will own problems from idea to production across AI product development, backend/full-stack, and system architecture, collaborating with the founding and engineering teams.

The role prioritizes exceptional engineering ability over title, with six days per week in the London office and 9am–9pm patterns.

Qualifications

• Outstanding software engineering fundamentals.
• A track record of building technically challenging products or systems.
• Exceptional ownership and problem-solving ability.
• Experience working in an early-stage or high-growth environment.
• A strong bias towards action and shipping.
• The ability to operate independently with limited structure.
• Genuine interest in AI and emerging technology.

Responsibilities

• Take ownership of difficult problems and move quickly from idea to production.
• Work on AI product development and engineering, backend and full-stack, and system architecture.
• Engage in rapid prototyping and product iteration for enterprise customers.
• Collaborate closely with the founding and engineering teams.

Skills

AI/Software engineering

Ownership & problem-solving

Early-stage experience

Independent work

Shipping mindset

Tools

Python

React

TypeScript

Job description

An early-stage AI technology company is scaling rapidly after securing major enterprise customers and is looking for exceptional engineers to join its growing team.

This is an opportunity to join at a genuinely early stage and work directly on products being deployed by some of the world's largest technology companies.

The Role

The company is looking for highly capable, generalist AI/Software Engineers who can take ownership of difficult problems and move quickly from idea to production.

You will work closely with the founding and engineering teams across areas including:

• AI product development and engineering
• Backend and full-stack development
• System architecture and infrastructure
• Rapid prototyping and product iteration
• Building solutions for enterprise customers
• Technical problem-solving in highly ambiguous environments

The current stack includes Python, React and TypeScript, although experience with these technologies is not essential. The priority is exceptional engineering ability rather than a perfect technology or job-title match.

What They're Looking For

The hiring bar is extremely high. Strong candidates are likely to have:

• Outstanding software engineering fundamentals.
• A track record of building technically challenging products or systems.
• Exceptional ownership and problem-solving ability.
• Experience working in an early-stage or high-growth environment.
• A strong bias towards action and shipping.
• The ability to operate independently with limited structure.
• Genuine interest in AI and emerging technology.

Candidates may come from leading technology companies, high-growth startups or founder-led environments. Experience at companies such as Meta, Amazon, Ramp, Linear, Cursor, Palantir or similar would be relevant, but exceptional candidates from other backgrounds will be considered.

The Environment

This is an extremely ambitious, high-intensity environment.

The current expectation is approximately six days per week in the London office, with a typical working pattern around 9am–9pm. There can also be periods where the team works beyond this level due to customer and product demands.

This is therefore best suited to someone who actively wants to operate at a very high pace and have an unusually large amount of responsibility early in their career.

Package

• Meaningful equity
• Potential annual bonus
• Lunch and dinner provided
• Weekly team sports and team meals
• UK relocation and visa support where required

Why Consider It?

You would be joining before the company transitions into a much larger scale-up, giving you the opportunity to:

• Work on AI products already being used by major enterprises.
• Take ownership well beyond a conventional engineering role.
• Work directly alongside the founding and senior engineering team.
• Help shape the technology and engineering culture.
• Have significant influence over the company's next stage of growth.
• Participate meaningfully in the upside of an early-stage company.

For exceptional engineers who want to build, move fast and take significant ownership, this is a rare opportunity to join a company at a highly formative stage.