Java Developer

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 experienceIf the role aligns with your expeirence, pelase apply with your updated CV