Senior Machine Learning Engineer - National Security (London)
AI in this role
We’re looking for a Senior Machine Learning Engineer to join a supportive, multidisciplinary team developing AI/ML systems to solve critical National Security challenges. As a Senior Machine Learning Engineer, you’ll lead onsite engagements with clients and stakeholders to translate their problems into robust, production-ready machine learning solutions. You’ll rapidly explore, prototype, and deploy ML approaches both within and beyond our core capability offerings, taking ownership from initial concept through to live operation. Working at the forefront of applied AI alongside experts across multiple disciplines, you’ll help users defend against Defence and National Security threats, directly contributing to safer, more resilient systems deployed where they matter most.
Mind Foundry works on some of the most complex and urgent challenges in Defence and National Security. We specialise in supporting customers across the community to make sense at the speed of relevance from the ever-increasing volumes of data collected by sensors and systems. We often find ourselves working at the edge in complex environments where power, compute, and bandwidth are in short supply. The work is challenging, the customer needs products and applications they can trust, and the sense of achievement is therefore substantial.
This is an opportunity to innovate at the forefront of applied machine learning, tackle high-impact real-world problems, grow your technical skills, and shape the way AI/ML solutions are delivered to critical operational environments.
Because of the nature of this work:
- You will need to hold existing or be eligible for UK Developed Vetting (DV), details of which can be found on the Gov UK website.
- Be expected to work primarily onsite at our clients’ sites in London. Please consider your commute when applying.
Key day-to-day activities:
- Lead technical scoping and make key architectural decisions to enable delivery of professional-level ML solutions.
- Design and build prototypes and robust, production-ready ML solutions.
- Work collaboratively with colleagues across the team (Product Managers, Machine Learning Scientists, Software Engineers) to solve critical National Security challenges.
- Maintain and develop a strong working knowledge of state-of-the-art ML methods, software tools and implementation methods.
- Write maintainable production code and promote best practices for code quality in a scientific codebase.
- Mentor and develop junior Machine Learning Engineers.
- Provide advice and explain core ML concepts to our customers and partners.
- Provide training to our customers and partners on Mind Foundry products and solutions.
Core kills & Experience:
- A degree in Computer Science, Applied Mathematics, Statistics, Physics, or a related STEM field (or equivalent practical experience).
- Strong engineer with demonstrated proficiency in programming languages such as Python, producing clean, reproducible, well-tested, and well-documented code suitable for long-term ownership and handover.
- Hands-on experience with production infrastructure, including Docker, Linux, CI/CD, MLOps, cloud platforms, and model serving architectures.
- Be able to work with state-of-the-art ML libraries to deliver powerful results quickly.
- Exceptional problem-solving skills and comfortable working in ambiguous, fast-moving environments, embedded with customers or delivery teams.
- Hold existing Developed Vetting (DV) level clearance, or willing and eligible to obtain and maintain UK security clearance to Developed Vetting (DV) level.
Nice to Have:
- Prior experience working with government customers, defence contractors, or in military environments.
- Ability to write technical material (documentation, published papers, internal technical notes etc).
- Experience with Natural Language Processing (NLP), Large Language Models (LLMs) or Image Processing.
- Experience in areas of model development, data processing and streaming (Spark, Kafka), microservices in python (Flask or FastAPI), and interactive visualisations and User Interfaces (Streamlit, Plotly, Gradio etc).
While we think the above experience is important, we’re keen to hear from people that believe they have valuable skills, ideas, or perspectives that will make an impact in this role. If our team and mission resonate with you, but you do not necessarily meet all our requirements, we still encourage you to apply.
Our Values
- We are one team: We share goals, responsibility and success. We support one another, value what fuels people and ensure no one is left behind.
- We work with purpose: We focus our effort where it matters most, we work hard, think smart and deliver meaningful results for our team, shareholders and customers.
- We laugh: We protect a positive environment. We have fun, feel safe, learn, grow and achieve more together.
- We move forward: We learn from setbacks and frustration, we support each other, solve problems together and don’t dwell on the past.
- We act with integrity: We hold ourselves to the highest standards and are trusted, discreet and reliable. We represent our clients with the same care as we represent ourselves.
What do we offer?
We believe in investing in our people by encouraging career and personal development that aligns with your goals and ambitions. We make sure all staff have the tools, time and support they need to shape their own professional development. We want to help you excel at what you do and support your growth within the company.
You’ll enjoy a competitive compensation package and great benefits such as:
- EMI options scheme
- 25 days of annual leave, plus Bank Holidays
- Salary Sacrifice Pension scheme
- Private Healthcare (including dental and optical cover)
- Group Life Cover
- Enhanced Parental and Sickness Leave
- UK Armed Forces Reservists Policy
- Workplace Nursery Scheme
- Volunteering Days
- Dog-friendly office
For more information, please visit our website www.mindfoundry.ai or email recruitment@mindfoundry.ai
Interview Process:
- Initial discussion with the People team
- TestDome coding exercise
- 1 hour interview with two members of the Science & Engineering Team
- 90 minute technical interview, including a 10-minute presentation and live coding exercise
- In person meet the team at our Summertown, Oxford office
How we rate this
Senior Machine Learning Engineer - National Security (London) at Mind Foundry rates 91 out of 100 for how much of the daily work is AI. That makes it Builds AI (AI Level 4 of 4). The level is about AI in the job, not seniority.
Builds AI. The job is building AI systems.
- ●●●● Builds AI80 to 100
- ●●●○ Works on AI60 to 79
- ●●○○ Uses AI40 to 59
- ●○○○ Little AI0 to 39
Levels come from how often the tools, models and workflows of the role are named in the posting itself. Open the description and count.
Prepare for this job
A free preview built only from this posting: what it asks for, what you could be asked in an interview, and how to adjust your resume.
Skills and AI tools this role asks for
Questions you could be asked
- How do you monitor a model once it's live, and how do you know it needs retraining?
- What NLP problem have you worked on, and how did you measure whether it actually worked?
- How would you decide a model or AI system is ready to ship?
- Tell me about a time a model underperformed in production. How did you find out, and what did you change?
Adapt your resume
- List these exact terms on your resume: ML Ops and NLP. An applicant tracking system matches the wording, not the idea.
- Attach one line of real, concrete experience to at least one of them — a tool named with nothing behind it rarely survives a human read.
- Lead with what you built, trained or shipped — this role is judged on the AI system itself, not the tools around it.
Want an expert to read your CV for this job?
Free. Send your CV and the role you want next. We reply by email within 2 to 4 business days.
Get a free CV reviewGet new machine learning engineer jobs (Builds AI ●●●●) by email
One email a week with the new machine learning engineer jobs (Builds AI ●●●●), each rated for how much AI is in the work. No recruiter spam, unsubscribe in one click.
Free. One email a week. Unsubscribe in one click.
Similar roles
Data roles that build AI, at other companies.
What kind of AI work fits you?
Answer 12 practical questions in about three minutes. Get a simple profile, the work it points to, and live roles to explore next.
Find my next step