About the company: At Mad Devs, you will be part of a company that values creativity, strategic thinking, and continuous improvement. You will work on meaningful projects that impact millions of users worldwide alongside a talented and supportive team.
Responsibilities:
- Own end-to-end telecom architecture: SIP edge (Kamailio/OpenSIPS), media & call control (FreeSWITCH), Python services bridging voice to AI, carrier integrations
- Scale platform to 10,000+ concurrent calls with tight latency/SLOs
- Design HA/disaster recovery: anycast SIP, active/active media, geographic failover
- Set engineering standards for telecom team (testing, load testing, code review, on-call)
- Mentor senior/mid engineers, raise technical bar
- Define voice quality observability & SLOs (MOS, jitter, packet loss, latency)
- Lead carrier strategy: SIP trunk vendors, redundancy, LCR, STIR/SHAKEN
- Partner with AI/product to keep latency budgets honest
Requirements:
- 8+ years engineering, 4+ years in telecom/VoIP in production
- Technical leadership: design docs, mentoring, cross-team decisions
- Deep production experience with FreeSWITCH + Kamailio OR OpenSIPS (custom modules, routing scripts, at scale)
- Strong SIP/RTP/SRTP/SDP/ICE; debug via pcap and SIP trace
- Operated voice platform at 1,000+ concurrent calls (knows diff to 10k)
- Strong Python; can work in Lua/Go/C as needed
- Production integration with PSTN/SIP trunk providers (Twilio, Telnyx, etc.), DID management, LCR
- Hands-on HA/failover for real-time systems
- Production Kubernetes (GKE/EKS) and Terraform
- English B2-C1, Russian B2
Conditions: At Mad Devs, you will be part of a company that values creativity, strategic thinking, and continuous improvement. You will work on meaningful projects that impact millions of users worldwide alongside a talented and supportive team. By joining our team, you will have the opportunity to make a real impact, grow your career, and contribute to developing cutting-edge solutions in the world of backend engineering.