Senior Lead VOIP Engineer

Realtime Recruitment; Dublin; Hybrid; EUR 120,000 - 180,000; Full time

Job summary

Realtime Recruitment is seeking a Senior Lead VOIP Engineer to own the architecture and technical direction of a next‑generation, carrier‑grade voice platform operating at global scale. You’ll be hands‑on with C/C++, SIP, RTP/RTCP, FreeSWITCH, Kamailio/OpenSIPS and RTPEngine to craft highly available, low‑latency VoIP infrastructure.

In this senior leadership role you’ll mentor engineers, set engineering best practices, and work with Engineering, DevOps, Product and QA to deliver

Qualifications

• 12+ years’ hands‑on experience in Telephony, VoIP or CPaaS environments.
• Experience with carrier‑grade voice infrastructure with high availability, low latency and global scalability.
• Strong hands‑on development experience with C/C++, with active coding experience in real‑time systems.
• Expert knowledge of VoIP protocols, including SIP, SDP, RTP and RTCP.
• Strong networking knowledge across UDP/TCP/IP, DNS and MPLS, with QoS understanding.
• Hands‑on experience with FreeSWITCH, Kamailio/OpenSIPS and RTPEngine.
• Strong experience designing and operating SBCs, media servers, NAT traversal and failover/load‑balancing.
• ICE, STUN and TURN, including WebRTC environments.
• Experience securing voice infrastructure using TLS, SRTP and fraud‑prevention controls.
• Proven experience designing carrier‑grade telephony platforms at significant scale, including millions of calls.
• Experience with PSTN/SIP trunking and global carrier integrations within CCaaS or CPaaS platforms.
• Strong troubleshooting and debugging skills, including live traffic analysis and major incident response.
• Experience with cloud‑based and distributed systems, ideally across AWS, GCP or Azure.
• Strong understanding of observability, security, resilience and performance optimisation.
• Previous technical leadership experience, including mentoring engineers and establishing engineering best practices.
• Ability to collaborate across Engineering, DevOps, Product, QA, Backend and API teams.

Skills

C/C++

SIP/VoIP

WebRTC

Networking

Observability

NAT Traversal

SBCs/Media servers

Distributed Systems

Tools

FreeSWITCH

Kamailio/OpenSIPS

RTPEngine

Job description

I am looking for a Senior Lead VOIP Engineer for my client. The Lead engineer will take ownership of the architecture and technical direction of a next-generation, carrier-grade voice platform operating at global scale. You’ll be hands‑on with C/C++, SIP, RTP/RTCP, FreeSWITCH, Kamailio/OpenSIPS and RTPEngine, while designing highly available, low‑latency and secure VoIP infrastructure. This is a senior technical leadership role where you’ll shape architecture, mentor engineers and work closely with Engineering, DevOps, Product and QA teams to deliver mission‑critical voice services.

Key Requirements

• 12+ years’ hands‑on experience in Telephony, VoIP or CPaaS environments.
• Proven experience designing and implementing carrier‑grade voice infrastructure with high availability, low latency and global scalability.
• Strong hands‑on development experience with C/C++, with active coding experience in real‑time systems.
• Expert knowledge of VoIP protocols, including SIP, SDP, RTP and RTCP.
• Strong networking knowledge across UDP/TCP/IP, DNS and MPLS, with a strong understanding of QoS, latency, jitter and packet loss.
• Hands‑on experience with FreeSWITCH, Kamailio/OpenSIPS and/or RTPEngine.
• Strong experience designing and operating Session Border Controllers (SBCs), media servers, NAT traversal and failover/load‑balancing solutions.
• Strong understanding of ICE, STUN and TURN, including WebRTC environments.
• Experience securing voice infrastructure using TLS, SRTP and fraud‑prevention controls.
• Proven experience designing carrier‑grade telephony platforms at significant scale, including millions of calls.
• Experience with PSTN/SIP trunking and global carrier integrations within CCaaS or CPaaS platforms.
• Strong troubleshooting and debugging skills, including live traffic analysis and major incident response.
• Experience with cloud‑based and distributed systems, ideally across AWS, GCP or Azure.
• Strong understanding of observability, security, resilience and performance optimisation.
• Previous technical leadership experience, including mentoring engineers and establishing engineering best practices.
• Ability to collaborate across Engineering, DevOps, Product, QA, Backend and API teams.

Key Skills

• Programming: C, C++
• VoIP/Telephony: SIP, SDP, RTP, RTCP, VoIP, CPaaS, CCaaS
• NAT Traversal: ICE, STUN, TURN
• WebRTC: WebRTC infrastructure and real‑time communications
• Networking: TCP/IP, UDP, DNS, MPLS
• QoS: Latency, Jitter, Packet Loss, Audio Quality Optimisation
• Carrier Infrastructure: PSTN, SIP Trunking, Global Carrier Integrations
• Architecture: Distributed Systems, High Availability, Scalability, Resilience
• Operations: Observability, Monitoring, Live Traffic Troubleshooting, Performance Tuning

Must hold Stamp 4, EU or Irish passport - this is a hybrid role in Dublin