VoIP Engineer (Telephony)

TL;DR

VoIP Engineer (Telephony): Designing and modernizing telephony infrastructure for an AI-driven platform with an accent on SIP protocol, FreeSWITCH/Asterisk, and high-volume call handling. Focus on building scalable integration solutions between telecom providers and AI services, ensuring fault tolerance and reliability.

Location: Fully remote across Europe

Company

hirify.global develops award-winning AI products and voice-first agentic architectures for tech corporations.

What you will do

• Design and modernize the telephony infrastructure to support AI platform integrations.
• Integrate with telecom providers across the US, LATAM, and Europe.
• Build call handling systems from scratch for both outbound and inbound traffic.
• Optimize telecom costs and resource allocation.
• Drive system reliability, scaling, and fault tolerance using Kamailio/OpenSIPS and rtpengine.
• Participate in 2nd and 3rd level support duties and on-call rotations.

Requirements

• 5 to 10 years of experience in VoIP and telephony engineering.
• Deep understanding of SIP protocol (messaging, methods, response codes, SDP) and troubleshooting signaling/media issues (NAT, RTP).
• Expertise in FreeSWITCH, Asterisk, or other b2ua, including dialplan development (Lua/XML) and performance optimization.
• Strong Linux administration skills, specifically with Debian or Ubuntu.
• Solid networking knowledge (TCP/IP, RTP/RTCP) and proficiency with analysis tools like tcpdump, Wireshark, and sngrep.
• Must be based in Europe.

Nice to have

• Experience with the Go programming language.
• Knowledge of Kamailio, OpenSIPS, or rtpengine.
• Familiarity with CI/CD, Docker, Ansible, and Kubernetes.
• Experience with large-scale telephony systems or voice biometrics projects.
• Experience with Node.js and FreeSWITCH Event Socket Layer (ESL).

Culture & Benefits

• Cutting-edge tech stack including Speech Technologies, NLP, and Generative AI.
• High engineering bar with real ownership and direct impact on production systems.
• Fast career progression within a senior-heavy team environment.
• Startup pace combined with enterprise stability and real revenue.
• 21 vacation days plus public holidays and 5 sick days.
• Private English lessons via Preply.