Software Developer

  • Sustain Recruit
  • 17/08/2026
Full time Information Technology Telecommunications

Job Description

Software Developer - C#/.NET/WinForms

Hertfordshire/Hybrid
Permanent | 37.5 hours per week

Build technology that makes a real difference

We're working with an established technology-for-good organisation that develops specialist software designed to help protect vulnerable people and support professionals working in critical areas.

They're looking for a Software Developer to join their talented development team and work on products that have a genuine real-world impact.

This would suit a junior to mid-level C# developer who enjoys building Windows applications, solving technical problems and wants to work somewhere where the software they create has a meaningful purpose.

The role

You'll join an experienced Agile/Scrum development team working on an established product suite alongside continued product development and enhancement.

Your main focus will be a C#/.NET Windows desktop application, working across the application stack from UI through to database.

You'll be involved across the development life cycle, including:

  • Developing new functionality using C# and WinForms
  • Working with SQL and relational databases
  • Contributing to technical design and architecture
  • Writing clean, maintainable and well-tested code
  • Participating in code reviews
  • Writing and maintaining automated unit and system tests
  • Helping improve the quality, reliability and maintainability of the product
  • Supporting releases and providing technical support where required
  • Working collaboratively with other developers and technical colleagues
  • Exploring appropriate use of AI within the development process

You'll have the opportunity to contribute ideas and influence how the software is built, rather than simply working through a list of predefined tasks.

What we're looking for

We're particularly interested in developers with experience in:

  • C#
  • .NET
  • WinForms/Windows desktop development
  • SQL/relational databases
  • Git or another source-control system
  • Automated testing and a strong interest in software quality

You don't need to have every technology listed. Strong C# fundamentals, good software engineering practices and a willingness to learn are more important.

Experience with any of the following would be advantageous:

  • Entity Framework
  • WPF
  • DevExpress or Telerik
  • MVVM or similar architectural patterns
  • Agile/Scrum
  • AI-assisted software development

About you

We're looking for someone who is curious, collaborative and proactive.

You'll ideally be someone who:

  • Takes pride in producing high-quality software
  • Enjoys understanding the problem behind the requirement
  • Is comfortable contributing ideas and challenging approaches constructively
  • Enjoys working as part of a team
  • Has a genuine interest in improving their technical skills
  • Wants to understand the impact their work has on the end user

Why join?

This isn't simply another C# development position.

You'll be working for an organisation where technology has a genuine positive impact on people's lives.

The business has been recognised as a Great Place to Work and has also received external recognition for its employee experience and culture.

You'll join a collaborative development environment where you'll be able to develop your technical skills, work with experienced engineers and contribute to software that has a genuine purpose.

Location & working arrangements

Hertfordshire/Hybrid

The role offers hybrid working, with an expectation that you'll be able to attend the office at least once a week.

Permanent | 37.5 hours per week

If you're a C# developer looking for your next opportunity and the idea of using your technical skills to build technology for good appeals to you, we'd love to hear from you.