Skills

Communication C# Go Encryption CI/CD Programming Asp.Net Agile .NET .NET Core

Job Specifications

Software C# Engineer

Salary: £50ph (Inside IR35)

12 months contract role

Remote role with 1 day per month on-site at the Rugby office

As Gi Group, we are supporting an international company delivering mission-critical solutions used daily by emergency services across the UK and Europe. The project focuses on Guardian, a call-taking and dispatching platform that enables 999 and 112 operators to respond effectively when every second matters.

As a Software C# Engineer, you will join an Agile engineering team working on complex, real-time communication systems that go far beyond standard CRUD applications. You will contribute to the core Guardian platform while also taking ownership of expansion products interfacing with 3GPP-compliant user equipment.

THE ROLE:

Your responsibilities will include:

Designing and developing C# components for high-concurrency SIP signaling and session management
Handling complex SIP headers and MIME bodies to support advanced call-handling features
Implementing real-time media processing using RTP/RTCP for Mission Critical Voice and Video
Developing MCData services, including HTTP and SIP MESSAGE-based communication
Managing XCAP configuration retrieval and XML document handling
Ensuring secure communications through OIDC authentication and MIKEY-SAKKE encryption
Collaborating closely with senior product leads and influencing the technical direction of the platform

THE CANDIDATE:

We are looking for an experienced engineer who is comfortable working with network-centric, highly available systems and real-time communication technologies.

4+ years of commercial experience with C# and .NET (.NET Framework and/or .NET Core)
Strong background in asynchronous and network-focused programming
Hands-on experience with WCF, SignalR, Entity Framework, ASP.NET, WebAPI
Solid understanding of SIP protocol stacks and RTP/RTCP
Experience working with complex XML schemas (XSD) and multipart/mixed MIME messages
Good knowledge of OOP, SOLID principles, and Agile / CI/CD practices

Nice to have:

Familiarity with 3GPP standards such as MCPTT or other MCX specifications
Experience with SRTP, TLS, or key management systems (KMS)
Previous exposure to emergency services environments, ESN, or police/fire control rooms

About the Company

Welcome to Gi Group! Your job, Our work! Gi Group is one of the world's leading companies providing a full range of HR Services. We offer Temporary, Permanent and Professional Staffing Services, Search & Selection and Executive Search as well as Outsourcing, Training, Outplacement and HR Consultancy. It is our mission to contribute to the evolution of the labour market and to emphasize the personal and social value of work. We aim to support people at each stage of their professional career and be at our clients' side as t... Know more