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Mid-Level Software Engineer

AdditionLeeds, Yorkshire🇬🇧United KingdomPosted 9 Sept 2026

Why This Role Stands Out

This hybrid role offers a fantastic opportunity to contribute to a growing cybersecurity SaaS business, leveraging modern technologies and AI to shape product development and engineering practices. You'll thrive here if you're a skilled software engineer eager to expand your full-stack capabilities in a collaborative environment with competitive compensation. Embrace the chance to grow your career and impact within an innovative and scaling company.

Quick Overview

Salary
£38k - £43k/yr
Seniority
Mid Senior
Employment type
Full Time
Work mode
Hybrid
Location
Leeds, Yorkshire, United Kingdom
SQLSQL ServerAWSAgile.NETPostgreSQLReact

Job Description

Mid-Level Software Engineer

Join a growing Cyber Security SaaS business that's investing heavily in its in-house engineering capability and the next stage of its product. You'll work across a modern cloud-based platform, building new features, improving existing functionality utilising AI and helping shape how the engineering team works as it scales.

Role Overview:

  • Location: Leeds/Hybrid (2 days per week in the office)
  • Package: £38,000- £43,000 per annum
  • Industry: SaaS / Cyber Security

What You'll Be Doing:

  • Working across a full-stack environment, with roughly a 60/40 split between backend .NET development and frontend React.
  • Building new product functionality while improving and maintaining an established SaaS platform.
  • Developing scalable APIs, services and cloud-based solutions within an AWS environment.
  • Working with modern versions of .NET, alongside React, PostgreSQL and Microsoft SQL Server.
  • Getting involved across the development lifecycle, from solution design and coding through to deployment and operations.
  • Collaborating closely with other engineers through pairing, code reviews and technical discussions.
  • Helping the team increase its focus on new product development by improving processes and reducing maintenance overhead.
  • Using AI-assisted development tools, with Claude currently the team's primary choice, to make development more efficient and the codebase easier to work with.
  • Working closely with product and wider teams to turn customer and business requirements into practical technical solutions.
  • Playing a part in strengthening the internal engineering function as the business continues to scale.

Main Skills Needed:

  • Minimum of 2 years experience in Software Engineering.
  • Commercial experience with .NET, ideally within backend services or APIs.
  • Experience with React and a willingness to contribute across the full stack.
  • Exposure to AWS or another major cloud environment; strong AWS experience would be a significant advantage.
  • Experience working with relational databases such as PostgreSQL or SQL Server.
  • Previous experience developing SaaS products as part of a multi-person engineering team.
  • Understanding of Agile development practices and the wider software development lifecycle.
  • Comfortable working across both new feature development and existing platform improvements.
  • An interest or experience in AI-assisted software development and openness to adopting new tools and technologies.
  • Strong problem-solving and communication skills, with the ability to work collaboratively rather than in isolation.
  • A Computer Science degree would be beneficial, but isn't essential.

What's in It for You:

  • Hybrid working with a relaxed approach to office attendance, typically around 2 days per week.
  • 25 days' annual leave.
  • Pension scheme.
  • Personal development budget for relevant courses, certifications and conferences.
  • Regular salary reviews.
  • The chance to work with modern .NET versions and a cloud-first AWS environment.
  • Exposure to AI-enabled development and the freedom to explore tools that can improve how the team builds software.
  • Genuine scope to develop your skills alongside experienced engineers while taking on increasing responsibility.
  • The opportunity to join an engineering function that's being built out internally, giving you plenty of visibility and influence as it grows.
  • Regular company social events and a central Leeds office.

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.

By applying you are confirming you are happy to be added to the Addition Solutions mailing list regarding future suitable positions. You can opt out of this at any time simply by contacting one of our consultants.

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