Telephony Engineer

Role overview Operate as the technical owner of the SIP signaling and carrier interconnect layer that carries millions of voice calls. The work centers on SIP trunking, session border controllers, codec selection, and intelligent routing across carrier partnerships, ensuring reliable inbound and outbound telephony at scale.

Responsibilities - Administer and tune SIP trunks, SBCs, and adjacent carrier interconnect components that terminate and originate high-volume voice traffic. - Design and maintain call routing logic, including number routing, least-cost routing, and failover strategies across carriers. - Select, configure, and troubleshoot audio codecs to balance call quality, bandwidth, and interoperability. - Monitor carrier health, call completion rates, and signaling performance, and respond to incidents in the telephony layer. - Collaborate with network, voice platform, and product teams to integrate new carriers, number ranges, or geographic footprints. - Document architecture, routing rules, and operational runbooks for the telephony infrastructure.

Requirements - Hands-on experience operating SIP infrastructure in production, including trunks and session border controllers. - Strong understanding of voice codecs and their trade-offs across quality, bandwidth, and compatibility. - Practical knowledge of call routing concepts such as number translation, failover, and traffic distribution across carriers. - Ability to diagnose signaling and call-quality issues using standard VoIP tooling and carrier-side logs. - Comfort working in a high-availability environment where telephony uptime directly affects customer experience.

Nice to have - Familiarity with multi-carrier orchestration, number management, or wholesale carrier integrations. - Exposure to adjacent telephony concerns such as STIR/SHAKEN, CDR processing, fraud detection, or regulatory compliance.