Senior Applied AI Engineer (Defence)

Security clearance: must be eligible for UK SC-level security clearance (UK national).

Visa sponsorship: we are not able to sponsor visas for this role.

About Neptune North

Neptune North is a high-performing technical consultancy. We build data, AI and software solutions for clients in defence, financial services and private capital, working on demanding problems in challenging environments. We were founded in 2024 as a joint venture between Oliver Wyman and Rokos Capital Management. We're headquartered in the centre of Newcastle upon Tyne, with a growing international footprint, and we're recruiting exceptional engineers across every level.

The role

We're looking for a Senior Applied AI Engineer to deliver AI-enabled applications for defence and to help provide technical oversight to a new and rapidly growing team. You will help lead, define and strengthen the applied AI capabilities that differentiate Neptune North and build a trusted reputation across defence clients. Potential projects might include fully engineered solutions, Proof of Concepts (POCs), and applied research to support future defence-relevant capabilities.

Responsibilities

• Influence the technical direction and play a key role in strengthening Neptune North's AI capabilities.
• Provide leadership/hands-on delivery in a wide range of AI projects.
• Work directly with clients to shape requirements, manage expectations, and to build trust.
• Contribute to winning work by helping to write compelling bids and high-quality technical proposals.
• Advocate knowledge sharing across the team and identify opportunities for reuse of capabilities.
• Regularly provide career and technical mentorship to other engineers to build a high calibre team.
• Demonstrate flexibility in taking on work aligned to evolving company priorities.
• Remain up to date with the latest developments in AI and advise on nascent technologies in the field.

What makes a great candidate

You don't need to meet every requirement to apply. If this role excites you, we'd like to hear from you.

• Minimum 5 years employment experience delivering and/or overseeing AI-enabled applications and workflows.
• Experience integrating AI components into applications and workflows, such as building Retrieval Augmented Generation (RAG) systems.
• Experience designing prompts and managing context for LLM applications.
• A solid understanding of LLM principles and transformer architectures, backed by core machine learning concepts and statistical methods.
• Practical experience evaluating LLMs and mitigating their weaknesses.
• Experience running AI applications in production, including monitoring and optimisation.
• Experience fine tuning or adapting models for specific scenarios, such as a specialist application or deployment to low power hardware.
• Experience building agentic systems, where models plan and act across several steps.
• Judgement about the risks and limitations of AI, including knowing when a statistical model or deterministic logic is the better choice.
• Strong programming skills, typically in Python, and experience in one or more other modern programming languages.
• A solid understanding of software engineering processes, and a drive to embed best practices in teams.
• Excellent verbal and written communication skills and the ability to adapt communication according to the audience.
• Ability to work effectively with ambiguity, while maintaining a disciplined, outcome-focused approach.
• Experience leading teams, with enthusiasm for sharing knowledge and collaborating.
• Strong academic foundations, typically a first-class from a leading university in Computer Science, Mathematics, AI, or a data related discipline.
• Experience in defence or national security is a strong plus.

What you can achieve

• Shape AI solutions that strengthen UK defence and national security.
• Play a critical role in building and nurturing a rapidly expanding team.
• Gain broad experience across interesting AI challenges applied to challenging environments.
• Contribute to meaningful technical decisions as part of a collaborative, low-ego engineering team.
• Work on a wide variety of interesting problems alongside high-calibre colleagues. Our culture is collaborative and supportive. Neptune North is a place where people help each other grow and feel a real sense of belonging.

25 days' holiday allowance plus bank holidays.

Matching pension contributions up to 6%.

Private health insurance through Bupa.

Discretionary bonus.

Travel

Neptune North works with clients across the UK's defence sector. Many engagements involve regular travel and time on client site. This could mean two to three days per week over an entire assignment, or shorter periods of full-time on-site working anywhere in the UK, at sites including Cheltenham, Bristol, Glasgow, Portsmouth or other defence hubs. We support travelling staff with full expenses and hotel arrangements, and we discuss client placements with you in advance. We are looking for engineers who see this variety as part of the appeal of consultancy work rather than a downside.

Our interview process is rigorous because the standard internally is high. For this role, it has three stages:

• Written questions, which you complete at a time that suits you.
• A first interview covering your CV, experience and career aspirations.
• A technical interview with members of our engineering team.

Equity, diversity and inclusion

At Neptune North we are committed to a work environment that embraces diversity, equity and inclusion. We believe diverse backgrounds, perspectives and experiences help us attract, develop and retain the best talent. We do not discriminate based on gender, age, race or ethnicity, identification as an LGBTQIA+ individual, religion, disability, or any other characteristic protected by relevant local law.