Senior Software Developer – Python

The Department for Business, Innovation, Science and Trade (BIST) helps businesses invest, innovate, export and grow across the UK. The Digital, Data and Technology (DDaT) directorate helps to deliver this by designing, building and running the services, platforms and technology that businesses and colleagues rely on every day.

Our teams work on a wide range of services and technologies, including:

• digital services that help businesses access government support, guidance and opportunities
• data and AI products that support decision making and enable innovation
• internal tools and services that help colleagues work more effectively
• secure technology and platforms that support critical government services
• cyber security services that protect systems, data and users

By joining DDaT, you'll work on services used by businesses, colleagues and citizens across the UK. You'll be part of multidisciplinary teams focused on improving services, solving complex problems and delivering better outcomes for users.

We are committed to creating an inclusive and supportive workplace. In recognition of this, we were named Best Public Sector Employer at the Women in Tech Employer Awards 2025!

You will join the Employee Experience portfolio, which looks after the digital services our own colleagues use every day: the staff intranet, the people directory, internal search, guidance supported by artificial intelligence, joining and leaving processes, and the tools that connect our people and workplace information. 

This is a hands-on senior engineering job. You will spend most of your time designing, writing, reviewing, testing, deploying and supporting production software, and you will lead development across a connected area of work. You will get to know a service from end to end, including its users, architecture, data, the systems it depends on and the ways it can fail, and use that understanding to make sound technical decisions and explain them clearly. 

You will work in a multidisciplinary team alongside product, delivery, design, user research, architecture, security, data and service management colleagues, and help other developers grow through pair programming, code review and practical feedback.

About you

You are an experienced developer who enjoys building software that people depend on to do their jobs. You write code that others can read, test and safely change, and you care as much about how a service behaves in production as about how it looks on your screen.

You think about the whole service, not just the part in front of you. You are comfortable with messy data, systems you did not build and problems that cross team boundaries. When something breaks, you want to understand why and stop it happening again.

You start from evidence about what users need rather than the first solution suggested, keep accessibility in mind throughout, and are happy to test an idea with a rough prototype first.

You explain technical risks and trade-offs in plain language to specialists and non-specialists alike, and you enjoy helping colleagues get better at their craft.

Main responsibilities

You will:

• Design, build, test, document, deploy and support production software, and review the work of other developers.
• Lead development across a connected area of work, planning and sequencing features and technical improvements.
• Design systems and integrations of moderate complexity, with clear interfaces between applications, services and data sources.
• Turn evidence about user and organisational needs into practical technical solutions, using prototypes and small experiments to test ideas.
• Apply modern development practices, including version control, code review, automated testing, continuous integration and continuous delivery.
• Build proportionate security, privacy and access controls into software and delivery, protecting sensitive staff and identity information.
• Help run services in production: investigate faults, take part in incident response and improve reliability, monitoring and support.
• Coach and mentor other developers and explain technical risks and trade-offs to specialist and non-specialist audiences. This role may include line management. All line managers are given support and guidance on how to line manage effectively.

It is essential that you have:

• Python as your primary programming language, specifically development and maintenance of Python web applications and services, using frameworks such as Django, FastAPI, Flask, or serverless architectures (Lead Criteria)
• The ability to write SQL queries and diagnose database-related issues in PostgreSQL, MySQL or similar
• The ability to deliver user-centred features and services within an Agile environment using practices such as Scrum or Kanban
• Are able to communicate technical and non-technical information to project stakeholders

It is desirable that you have:

• Experience of working on internal workplace, staff directory or staff-facing digital services.

Security clearance: Security Check