Realtime Backend Engineer (LiveKit / SIP)

Intro
_For this position we are only looking for candidates located in Greece._
Nairon is a Swiss startup building AI voice agents that answer and make phone calls for businesses. Our platform runs real-time conversations over the phone and on the web, connected to our customers' telephony and business tools. We value clear communication, thoughtful engineering, and a collaborative approach to problem-solving. Join us as we continue to develop tools that make a difference.
Tasks
As a Realtime Backend Engineer at NAIRON, you will build the services that carry every call and every event through our platform. Your responsibilities will include:
* Designing, building and running microservices around our _LiveKit_\-based real-time media platform.
* Working with messaging and realtime data systems such as _NATS_, Kafka and Redis-compatible stores.
* Connecting phone calls to the platform: SIP trunks, routing, transfers and call quality, together with the team.
* Building integrations with our customers' systems, such as CRMs, calendars and ticketing tools.
* Running services in the cloud with _Docker_ and _Kubernetes_, with metrics, logs and traces you can trust.
* Taking part in code reviews, technical discussions and architectural planning.
Requirements
Experience:
A mid-level to senior backend engineer with experience running distributed, real-time systems in production.
Technical Skills:
Required:
* Strong _Python_ (asyncio, _FastAPI_ or similar); _TypeScript_ or Go is a plus.
* Microservice design: messaging, idempotency, backpressure and failure handling.
* Experience with _NATS_, Kafka or a comparable realtime messaging or database system.
Nice to have:
* _LiveKit_, WebRTC or other real-time media.
* SIP and VoIP: trunks, _Kamailio_ or similar proxies, RTP troubleshooting.
* Cloud experience (_AWS_ or similar), _Kubernetes_ and observability with _OpenTelemetry_ and _Grafana_.
Communication:
* _English proficiency is essential, both written and spoken, as it is the working language for all positions._
Soft Skills:
* Calm, systematic debugging when something breaks under load.
* Ability to work independently in a distributed team and to write things down.
Benefits
* Flexible Work Setup: Work fully remotely or from a co-working space — whichever suits you best.
* Equipment Provided: Company laptop and phone provided for all employees.
* Collaborative Environment: Join a small, agile team where your contributions have a direct impact.
* Growth Opportunities: See the whole path of a call, from the phone network to the AI agent, and grow into telephony or AI work.
Closing
If you enjoy building systems that have to work in real time, we'd love to hear from you.