Software Engineer (Machine Learning)

About Lightsonic

Lightsonic finds water leaks by turning telecoms fibre that's already in the ground into a sensing network. We work with water utilities across the UK and Europe to detect leaks that might otherwise run undetected for months — already saving millions of litres every day, and rising. Backed by strong investment and growing customer traction, we're in an exciting phase of rapid growth and expansion. As an early-stage company with proven technology, we're uniquely positioned to transform how critical infrastructure is monitored, creating a more sustainable and resilient environment.

Who you are

• Required:
• Someone excited about creating positive environmental impact through technology and motivated by solving real-world problems that matter.
• Adaptable individual who thrives in a startup environment - getting involved in all aspects of product development, from writing code and testing models to meeting customers and even assisting with on-site leak verification.
• Software engineer with 4+ years’ experience and expertise in Python and SQL.
• Experience designing and building production data pipelines and data-intensive systems.
• Experience working closely with machine learning engineers on model development and deployment.
• Desirable:
• Direct experience with elements of our technology stack (Azure IoT Edge, Azure Storage, dbt, Apache Iceberg, Trino, Dagster, Dask).
• Experience with IoT data processing or edge computing environments.
• Familiarity with time-series data and acoustic signal processing.

What the job involves

• Designing and implementing data and machine learning systems that run from edge devices in the field through to cloud, scaling to hundreds of terabytes of sensor data — with significant ownership over technical decisions.
• Working with complex multidimensional time-series and acoustic data.
• Collaborating with machine learning engineers to train, deploy, monitor, and improve models in production.
• Working on the customer-facing side of the product, from reporting and APIs through to the field apps used to verify leaks on site.
• Taking ownership of production systems, including testing, observability, performance, reliability and troubleshooting.
• Exploring and solving problems where the solution isn't always known upfront — combining engineering with experimentation and real-world feedback.

Application Process

• Initial screening interview (20 minutes).
• Technical interview (90 minutes).
• Behavioural Interview (60 minutes).

Initial interviews will be held via Microsoft Teams. We prefer to hold the final co-founder meeting in person when possible. Candidates must have the right to work in UK or Norway. We'll ask for references at offer stage.

Company Benefits & Perks

• Competitive salary.
• Participation in company share option scheme.
• Fast-paced and team-oriented environment where you will be instrumental in the direction of the company.
• Remote first (with occasional travel for customer meetings and team collaboration).
• Life assurance and medical insurance.
• 25 days holiday per year.
• Home office setup allowance.