Senior Developer

Senior / Experienced Software Developer (VoIP / SIP)

Location: Guildford (Hybrid) – must live within a 2-hour commute Salary: £55,000 – £65,000 (DOE)

The Opportunity

An established technology business is looking for a Senior / Experienced Developer to join a small, specialist software team. You’ll help evolve an enterprise-level SIP platform and build secure, scalable services and integrations.

The Role

Design, develop and enhance a SIP/VoIP platform and associated servicesBuild REST APIs and value-add servicesIntegrate with external systems including AI-driven voice, transcription and analytics servicesTroubleshoot SIP/RTP issues and improve platform reliabilityContribute to secure development practices and compliance (ISO27001, PCI-DSS)

Key Skills & Experience

Strong SIP / VoIP protocol knowledge (SIP, SDP, RTP)5+ years’ experience with Python or another OO languageREST APIs, Flask/Django and secure systems developmentLinux (Ubuntu), Docker and Git-based workflowsWireshark for SIP/RTP troubleshootingExcellent communication skills

Desirable

FreeSWITCH, Kamailio or WebRTCC/C++, OAuth2/Auth0CI/CD, Kubernetes, MongoDB or MySQL

Benefits

24 days’ holiday + bank holidaysHybrid Working (1 day per month in office) Pension, Life Insurance & Private MedicalBirthday & volunteering day offDiscounts & Cycle to Work scheme

The client is looking to fill this opportunity immediately, so please apply ASAP or feel free to drop me an email with any questions to owen @ serlimited . com.

SER-IN