About the role
We are hiring a Senior VoIP Engineer to help shape and evolve a large-scale real-time communications platform, including the migration from legacy infrastructure to a modern architecture.
This role sits at the intersection of telecom, networking, and software engineering, and requires practical, production-grade experience across all three. You will contribute directly to architectural decisions, build new services, and improve voice systems that customers rely on every day.
This is a developer role — not an integrator or operator position. We are looking for someone who has written code that routes, manipulates, and reasons about SIP traffic at scale.
What you'll do
* Design and develop services for a production-grade real-time communications platform.
* Build and maintain telephony applications using open-source and commercial platforms.
* Contribute to and help lead the migration from legacy infrastructure to a modern architecture.
* Design and implement call routing logic, SIP signaling flows, and media handling.
* Troubleshoot complex issues in live voice environments — signaling, media, performance, and reliability.
* Partner closely with operations and cross-functional engineering teams to ensure service stability and scalability.
What we're looking for:
Required
* 5+ years as a developer building VoIP / SIP systems — not solely operating or integrating commercial platforms.
* Hands-on production experience with both layers of an open-source SIP stack:
A B2BUA / media server: Asterisk or FreeSWITCH
A SIP proxy / routing layer: Kamailio or OpenSIPS
* Proven track record building and operating voice platforms in production.
* Solid understanding of SIP signaling, dialog state, NAT traversal, and real-time media behavior.
* Comfort reading and writing code, not only configuration.
* Advanced English proficiency (written and spoken).
* Strong analytical and problem-solving skills.
Strong plus
* Python for automation, tooling, or service development.
* SQL and cloud environments (AWS, Azure, or GCP).
* Containerization technologies (Docker, Kubernetes).
* Event-driven architectures and messaging systems (Kafka, RabbitMQ, NATS).
* DevOps and automation tooling (Terraform, Ansible, CI/CD pipelines).
* Exposure to RTPengine, Homer SIP capture, WebRTC gateways, or SBCs.
* Experience contributing to or maintaining infrastructure-as-code.
Why this role
* Fully remote with a flexible working model.
* Direct ownership of architectural decisions on a platform handling real production traffic.
* High-impact migration project — your work shapes the next generation of the platform.
* Tight, technical team where engineering quality is a first-class concern.
* Continuous learning culture with support for training and development.