Senior Full-Stack Developer

Addition; Greater London; Hybrid; GBP 70,000 - 95,000; Full time

Benefits offered by this job

Annual bonus

Birthday off

Hybrid work: Shoreditch office

£1,000 learning & development budget

Remote work up to 4 weeks/year

High-spec Windows or MacBook

Meaningful AI projects in UK govt

Autonomy & diverse tech challenges

Job summary

Addition is seeking a senior Full-Stack Developer to design, build and deploy scalable software for UK government projects. You will work across frontend, backend and data pipelines, balancing hands-on engineering with technical leadership.

The role uses Python, TypeScript, SQL with Azure and GCP, Docker and Linux; you’ll mentor engineers, review code, and collaborate with stakeholders while delivering secure, reliable solutions in a hybrid setup with one day per week in Shoreditch.

Qualifications

• Strong commercial experience as a Full-Stack Developer or Software Engineer working on complex applications.
• Advanced Python and TypeScript skills with frameworks such as FastAPI, Pydantic, Node.js, Express or Next.js.
• Strong React experience and confidence building sophisticated, user‑friendly front‑end applications.
• Strong SQL and database experience, including performance optimisation and data integrity.
• Hands‑on knowledge of cloud deployments, ideally Azure or GCP.
• Confident working with Docker and Linux‑based environments.
• Advanced Git knowledge, including branching, merging, pull requests, code reviews and collaborative workflows.
• Experience with CI/CD practices and automated testing.
• Strong stakeholder communication skills, including presenting complex technical concepts clearly.
• Experience mentoring or supporting less experienced engineers.
• Excellent problem‑solving, organisation and attention to detail.

Responsibilities

• Design, build and deploy scalable full‑stack software solutions across front‑end, back‑end and data engineering.
• Develop high‑quality APIs, backend services and complex data pipelines with performance and reliability in mind.
• Work extensively with Python, TypeScript and SQL across a variety of applications and integrations.
• Support the delivery of technology solutions helping public‑sector organisations adopt AI and machine learning effectively.
• Deploy and maintain applications within cloud environments such as Azure and GCP.
• Use Docker and Linux to support reliable application deployments, including containers, storage, volumes and permissions.
• Review code and pull requests, maintaining strong standards around security, testing and maintainability.
• Design and optimise database solutions to protect data integrity and improve application performance.
• Troubleshoot complex technical challenges and continuously improve existing platforms and services.
• Mentor junior engineers and help establish strong engineering practices across the wider team.
• Communicate technical decisions, project progress and outcomes clearly to technical and non‑technical stakeholders.
• Contribute to technical planning, identify potential risks and recommend new technologies or approaches.

Skills

Full-Stack Development

Python

TypeScript

FastAPI

Pydantic

Node.js

Express

Next.js

React

SQL

Database design

Azure

GCP

Docker

Linux

Git

CI/CD

Testing

Code reviews

Security

Stakeholder communication

Mentoring

Problem solving

Tools

Docker

Linux

Azure

GCP

Git

CI/CD

Job description

Join a growing technology consultancy specialising in driving AI and machine learning adoption across the UK government sector. You’ll play a key role in building sophisticated software and data solutions, combining hands‑on engineering with technical leadership to help deliver secure, scalable technology with real‑world impact.

Role Overview:

• Package: £75,000 basic salary + annual performance bonus and perks

What You’ll Be Doing:

• Design, build and deploy scalable full‑stack software solutions across front‑end, back‑end and data engineering.
• Develop high‑quality APIs, backend services and complex data pipelines with performance and reliability in mind.
• Work extensively with Python, TypeScript and SQL across a variety of applications and integrations.
• Support the delivery of technology solutions helping public‑sector organisations adopt AI and machine learning effectively.
• Deploy and maintain applications within cloud environments such as Azure and GCP.
• Use Docker and Linux to support reliable application deployments, including containers, storage, volumes and permissions.
• Review code and pull requests, maintaining strong standards around security, testing and maintainability.
• Design and optimise database solutions to protect data integrity and improve application performance.
• Troubleshoot complex technical challenges and continuously improve existing platforms and services.
• Mentor junior engineers and help establish strong engineering practices across the wider team.
• Communicate technical decisions, project progress and outcomes clearly to technical and non‑technical stakeholders.
• Contribute to technical planning, identify potential risks and recommend new technologies or approaches.

Main Skills Needed:

• Strong commercial experience as a Full‑Stack Developer or Software Engineer working on complex applications.
• Advanced Python and TypeScript skills, with experience using frameworks such as FastAPI, Pydantic, Node.js, Express or Next.js.
• Strong React experience and confidence building sophisticated, user‑friendly front‑end applications.
• Strong SQL and database experience, including performance optimisation and data integrity.
• Hands‑on knowledge of cloud deployments, ideally Azure or GCP.
• Confident working with Docker and Linux‑based environments.
• Advanced Git knowledge, including branching, merging, pull requests, code reviews and collaborative workflows.
• Experience with CI/CD practices and automated testing.
• Comfortable reviewing other developers’ code and maintaining high engineering standards.Strong stakeholder communication skills, including presenting complex technical concepts clearly.
• Experience mentoring or supporting less experienced engineers.
• Excellent problem‑solving, organisation and attention to detail.

What’s in It for You:

• Competitive compensation package with an annual performance bonus.
• 26 days’ annual leave, plus bank holidays and your birthday off.
• Enhanced family leave.
• £1,000 annual learning and development budget.
• Hybrid working with just one day per week in the Shoreditch office.
• Work remotely from anywhere in the world for up to four weeks each year.
• Choice of a high‑spec Windows machine or MacBook.
• Exposure to meaningful AI and machine learning projects across the UK government sector.
• Plenty of autonomy and the opportunity to work across different technologies and technical challenges.
• Supportive, entrepreneurial culture with regular team socials, free snacks and drinks.
• Opportunities to develop your technical leadership while remaining hands‑on.

Careers move fast. Let’s make sure yours is heading the right way.

We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, colour, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.