About the Role

We are building a next-generation cloud telephony and Voice AI platform, similar to Exotel, Plivo, Twilio and Knowlarity.
We are looking for a Principal VoIP & Telephony Infrastructure Engineer to build the core telephony infrastructure powering our platform.
You will own SIP, RTP, FreeSWITCH/Kamailio, SIP trunking, carrier integrations, call routing and real-time audio streaming.
What You'll Work On
Build and scale carrier-grade SIP/VoIP infrastructure
Design call routing, SIP trunking and carrier integrations
Work with FreeSWITCH, Kamailio, OpenSIPS or Asterisk
Build high-concurrency inbound and outbound calling infrastructure
Develop real-time RTP/WebSocket audio streaming
Build infrastructure for virtual numbers, call recording, DTMF, transfers and conferencing
Optimize latency, reliability, call quality and scalability
Build integrations with telecom operators and SIP providers
Work closely with our Voice AI team to connect telephony with AI agents




What We're Looking For
5+ years of strong VoIP/telephony experience
Deep understanding of SIP, RTP, SDP, SIP Trunking and PSTN
Strong hands-on experience with FreeSWITCH, Kamailio, OpenSIPS or Asterisk
Experience building high-concurrency production voice systems
Robust Linux and networking fundamentals
Experience with Go, C/C++, Python or Node.js
Experience with telecom carriers/SIP providers is a big plus
Bonus
Experience at a CPaaS, cloud telephony, telecom or contact-center company such as Exotel, Plivo, Twilio, Acefone, Ozonetel or Knowlarity.

Location: [Bangalore]
Experience: 5+ years
Type: Full-time

If you have built the infrastructure behind large-scale voice platforms and want to build the next generation of telephony + Voice AI, we'd love to hear from you.

📌 Principal VoIP (Bengaluru)
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