Senior Software Engineer

We’re looking for a Senior Software Engineer with strong Python and infrastructure experience to play a key role in developing and maintaining a business-critical smart meter platform.

You’ll be responsible for building the backend services that power the platform, from ingesting MQTT traffic from thousands of deployed devices through to APIs and internal services that ensure data remains reliable and consistent.

This is an opportunity for someone who enjoys genuine ownership. You’ll deploy the services you build, take responsibility for them in production and help ensure the platform remains stable, observable and reliable.

The environment is primarily focused on software engineering, with operations forming part of the role rather than becoming a full-time firefighting exercise. You’ll also play an important role in supporting the migration of existing services from AWS into a DigitalOcean Kubernetes environment.

How you’ll spend your day

You’ll take ownership of Python services that sit at the heart of a large-scale connected device platform, working across backend development, infrastructure and production operations.

Your responsibilities will include:

• Designing, building and maintaining production-grade Python services supporting thousands of deployed smart meters.

• Developing and supporting data ingestion services handling MQTT traffic from connected devices.

• Building APIs and internal backend services that provide reliable access to platform data.

• Designing resilient services that handle asynchronous processing, message-driven workflows and potential system failures.

• Taking ownership of services throughout their lifecycle, from development and testing through to deployment and production support.

• Deploying and managing your own services using Docker and Kubernetes.

• Supporting the migration of existing services and infrastructure from AWS into a DigitalOcean Kubernetes environment.

• Monitoring service health and performance, investigating issues and ensuring systems remain stable and observable in production.

• Debugging complex issues across multiple layers, including devices, networks, message brokers and application services.

• Working with AWS services and infrastructure, including technologies such as EC2, DynamoDB and SQS.

• Helping transfer ownership of existing services and reducing reliance on other senior members of the engineering team.

• Making sound technical decisions independently and contributing to the continued improvement of the wider platform., Should we both wish to proceed, we will submit your details to the client and be in touch regarding the outcome and any further steps.

We’re looking for an experienced Python engineer who is comfortable taking genuine ownership of backend services in production. You’ll have strong software engineering fundamentals alongside the infrastructure knowledge needed to deploy, monitor and troubleshoot your own work.

You’ll ideally bring:

• 5+ years of commercial experience developing production Python applications and services.

• A strong track record of owning backend services from design and development through to deployment and ongoing production support.

• Strong backend engineering experience, including API development using frameworks such as FastAPI, Flask or similar technologies.

• Experience working with asynchronous processing, data modelling, automated testing and resilient message-driven systems.

• Strong Linux experience and hands-on knowledge of Docker and Kubernetes.

• Experience deploying, managing and troubleshooting containerised applications in production environments.

• Working knowledge of cloud infrastructure and AWS services, ideally including EC2, DynamoDB and SQS.

• Experience taking operational ownership of services and diagnosing issues when systems become unhealthy.

• Strong troubleshooting skills, with the ability to investigate issues across application, infrastructure, networking and connected devices.

• The confidence and judgement to work autonomously and make informed technical decisions.

It would also be beneficial to have experience with:

• MQTT or other messaging technologies, particularly where clients may have unreliable or intermittent connectivity.

• Time-series data and high-volume data processing.

• Embedded systems, telemetry, IoT or energy-sector technology.

• Python profiling, performance optimisation and troubleshooting complex production workloads.

• Migrating services between cloud or infrastructure environments.

Our client are a leading UK provider of smart, sustainable heat-network solutions, specialising in end-to-end services for local authorities, housing associations, and private developers. With decades of experience, their expertise ranges from design and build through to operation, metering, billing, and optimisation. Their mission centres on driving energy efficiency, reducing carbon, and delivering reliable, affordable heat for residents.