Tin Can
Senior VoIP Engineer
$175K–$195K
Seattle · On-site · Senior · Full-time · Posted Aug 24, 2026
- Experience
- 5+ years.
About the job
Own and improve Tin Can’s production SIP and media plane, ensuring reliable call routing, quality, capacity, and security as the service scales.
What you'll do
- Own and tune Kamailio, FreeSWITCH, and carrier trunking; build routing logic, dial plans, and integrations.
- Test and troubleshoot calls using SIP scenarios, packet captures, and call-quality metrics; model and load-test capacity.
- Extend the voice service to new countries and harden signaling and media against fraud and security risks.
What they ask for
- 5+ years building and operating production real-time voice systems, with hands-on Kamailio and FreeSWITCH experience.
- Strong SIP and RTP knowledge, including location services, dialog state, transfers, Path routing, and NAT traversal.
- Experience diagnosing production calls from packet captures and SIP traces to root cause.
- Treats configuration as code and infrastructure as reproducible; fluency using AI for diagnosis, analysis, and testing.
Nice to have
- Experience with rtpengine, Homer/HEP, SIPp, Prometheus exporters, STIR/SHAKEN, or carrier interconnect.
- WebRTC internals (ICE, DTLS-SRTP, TURN) and bridging WebRTC to SIP.
Pay
USD $175K – $195K base salary
Tools
Kamailio, FreeSWITCH, AWS, SIP, RTP, ESL, Lua, SIPp
AI focus
Use AI as a multiplier across diagnosis, analysis, and testing.
Model-written summary · the original posting is authoritative