Senior Machine Learning Engineer – Java / Cybersecurity (Belfast, UK - Hybrid)

Senior Machine Learning Engineer – Java / Cybersecurity

Belfast | Hybrid

Our client is hiring a Senior Machine Learning Engineer to join a team building a new cybersecurity product from the ground up. This is an opportunity to work at the intersection of machine learning, cybersecurity and large-scale software engineering, helping shape a new product as it moves from concept into development.

You’ll work in a fast-paced engineering environment, designing and implementing intelligent detection capabilities that identify abnormal behaviour across large data sets. You’ll also have a genuine voice in technical decisions, architecture and product direction.

What you’ll be doing:

• -Design and develop machine-learning and statistical anomaly-detection capabilities.
• -Build production-grade services using Java.
• -Develop approaches for identifying behavioural anomalies where labelled data may be limited or unavailable.
• -Implement techniques including distribution divergence, robust z-scores, Earth Mover’s Distance, baseline modelling and drift detection.
• -Apply unsupervised techniques such as Isolation Forest and related approaches.
• -Build numerical and ML functionality using Java libraries such as Apache Commons Math, Smile, XGBoost4J or ojAlgo.
• -Work directly with columnar data stores to generate and compute features at scale.
• -Contribute to technical architecture and engineering decisions.
• -Collaborate closely with software engineers, product teams and other technical stakeholders.
• -Deliver high-quality, scalable software with a strong focus on customer experience.

What we’re looking for:

You’ll ideally have:

• -5+ years of commercial software engineering experience.
• -5+ years of production Java development.
• -Strong hands-on experience with statistical anomaly detection.
• -Experience applying unsupervised machine-learning techniques.
• -An understanding of how to evaluate anomaly-detection models when labelled data is unavailable.
• -Experience implementing numerical or statistical techniques directly in Java.
• -Experience working with high-volume or columnar data platforms.
• -Strong problem-solving and analytical skills.
• -Excellent communication skills and the ability to work effectively within an Agile engineering team.

Particularly useful experience:

Any of the following would be highly advantageous:

• -Cybersecurity, UEBA, fraud detection or telemetry scoring.
• -Multi-signal or ensemble scoring.
• -Behavioural analytics.
• -Gradient-boosted models such as XGBoost.
• -Security or threat-detection platforms.
• -Large-scale system integration.
• -Data-intensive SaaS products.

Education:

A degree, or equivalent experience, in a highly quantitative discipline such as:

• -Mathematics.
• -Physics.
• -Statistics.
• -Computer Science.
• -Engineering.
• -Another relevant quantitative field.

Why join?

This is a rare opportunity to join at the early stages of a new product and help define how machine learning is applied within a developing cybersecurity platform.

You’ll have the chance to influence technical direction, solve complex real-world problems and build sophisticated detection technology rather than simply maintaining an established system.

If you’re a senior Java engineer with strong machine-learning experience — or an ML engineer with genuine production Java depth — we’d be keen to hear from you.