Full job description





Java Developer (SIP/VoIP)Ipswich (Hybrid) | 6 Month Contract | Inside IR35
My client, a leading telecoms company, is looking for an experienced Java Developer to join a team delivering next-generation voice and communications platforms. This is an exciting opportunity to work on large-scale telecoms services, cloud technologies and AI-powered voice solutions.
What You’ll Be Doing*Developing and enhancing SIP-based voice applications using Java
*Working with JAIN SLEE and SIP Servlet frameworks
*Supporting and integrating voice platforms including FreeSWITCH and Asterisk
*Deploying and supporting solutions across AWS, Azure and GCP
*Integrating Speech-to-Text, Text-to-Speech and AI-driven voice services
*Troubleshooting voice quality, call routing and network performance issues
Essential Skills*Strong commercial Java development experience
*Experience with SIP, VoIP, RTP/RTCP and SDP
*Knowledge of JAIN SLEE and/or SIP Servlet frameworks
*Experience with FreeSWITCH or Asterisk
*Cloud experience across AWS, Azure or GCP
*Strong troubleshooting skills within telecoms or voice environments
Nice to Have*Docker and Kubernetes
*WebRTC
*Telecoms security protocols including TLS and SRTP
*Metaswitch Rhino SLEE or Oracle OCCAS experience
If the role aligns with your expeirence, pelase apply with your updated CV