Contact SmartSourcing PLC
SmartSourcing PLC
Software Engineer
Birmingham, West Midlands
- Hours
- Full Time
- Posted
- 1 day ago
- Salary
- £350 - 450 - Day
- Recruiter
- SmartSourcing PLC
- Closes
- 05 Apr 2026
- Course
- No
- Recruiter Type
- Direct Employer
Description
C# Software Engineer, Remote, 12 month contract, Inside IR35
Must be eligible for BPSS clearance. Working one day a month on site in Rugby
Real-time system experience is essential for this role, working within an Agile delivery team, you will move beyond standard CRUD applications to solve complex network and real-time communication challenges. You will lead the development of expansion products that interface with 3GPP-compliant User Equipment (UE).
What You’ll Do:
* SIP Signaling & Session Management: Develop C# components for high-concurrency SIP sessions, managing complex headers and MIME bodies to support features like "First-to-Answer" and Group Regroups.
* Real-Time Media Plane: Implement RTP/RTCP media handling for Mission Critical Voice (MCPTT) and Video (MCVideo), ensuring seamless floor control (transmission rights) in half-duplex environments.
* Data & Configuration: Build handlers for MCData services (SDS, File Distribution) using HTTP and SIP MESSAGE requests, and manage XCAP retrieval logic for XML configuration documents.
* Secure Communications: Integrate OIDC authentication flows and MIKEY-SAKKE encryption to ensure media transport remains secure and resilient.
Essentials skills:
* C# / .NET Framework / .NET Core Mastery: 3+ years of professional experience with a deep focus on asynchronous network programming.
* .NET Frameworks Experience: WCF, SignalR, EF, ASP.NET, WebAPI
* Protocol Expertise: A solid understanding of the SIP Protocol Stack (INVITE, PUBLISH, SUBSCRIBE, etc.) and experience with RTP/RTCP stacks.
* Data Handling: Proficiency in parsing complex XML schemas (XSD) and handling multipart/mixed MIME bodies.
* Software Engineering Principles: Strong grasp of OOP, SOLID principles, and modern CI/CD workflows (Git, Pull Requests, Agile).
Preferred skills:
* 3GPP Standards: Familiarity with TS 24.379 (MCPTT) or related MCX standards.
* Security: Experience with SRTP, TLS, or Key Management lifecycles (KMS). xjnqpsq
* Domain Knowledge: Previous experience with UK Police Control Room environments or the Emergency Services Network (ESN).
SmartSourcing are a Disability Confident Employer and we promote, celebrate and value diversity, we are committed to promoting equality and inclusion for all
Ad ID: 5417812338
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