FreeSWITCH Software Engineer (Remote)

📋 Description

• • Own and evolve Telnyx’s carrier-grade voice platform: you will be the primary technical authority for our FreeSWITCH back-to-back-user-agent (B2BUA) service that processes millions of call-minutes per day across six continents.
• • Design, code, test, and deploy new FreeSWITCH modules in C/C++ that extend SIP, RTP, WebRTC, and media-processing capabilities; your commits will immediately impact global call routing, transcoding, and recording features used by thousands of enterprise customers.
• • Diagnose and resolve complex production incidents—SIP 5xx storms, memory leaks, race conditions, kernel-level packet loss—using gdb, perf, tcpdump, and custom tracing; you will drive root-cause analyses and author post-mortems that prevent recurrence.
• • Optimize real-time media paths: profile CPU cache usage, reduce context switches, tune kernel network parameters, and implement zero-copy RTP forwarding to shave milliseconds off latency for high-definition voice and video calls.
• • Expand horizontal scale: refactor monolithic configurations into modular profiles, integrate with Kubernetes-based micro-services, and automate canary rollouts so new FreeSWITCH versions reach production safely and frequently.
• • Contribute upstream: triage open GitHub issues, submit patches to the FreeSWITCH core, and collaborate with the open-source community to influence the roadmap for features like STIR/SHAKEN, SRTP-DTLS, and AV1 codec support.
• • Build observability that operators love: create Prometheus exporters, Grafana dashboards, and distributed tracing spans that expose SIP dialog life-cycles, codec negotiation metrics, and per-carrier QoS scores in real time.
• • Partner with product managers to translate customer requirements (call-transfer, voicemail transcription, fraud detection) into technical epics, estimate effort, and deliver iterative releases every two weeks.
• • Mentor junior engineers through pair-programming, code reviews, and lunch-and-learn sessions on topics such as SIP RFC nuances, Valgrind leak hunting, and secure RTP best practices.
• • Champion reliability engineering: define SLOs for PDD (Post Dial Delay), PESQ voice quality, and call-setup success rates; build chaos-engineering experiments that validate failover across multi-region POPs.
• • Automate tedious tasks: write Ansible playbooks and Terraform modules that provision bare-metal and cloud instances, compile FreeSWITCH with custom modules, and run regression test suites in CI/CD pipelines.
• • Influence architecture decisions: evaluate when to adopt new signaling protocols (SIP over QUIC, HTTP/3), containerize media functions, or offload DSP to FPGA/GPU cards for ultra-high-density transcoding.
• • Ensure security and compliance: implement TLS 1.3, SRTP, and STIR/SHAKEN certificate management; perform threat modeling and penetration-test reviews to protect customer call data and meet PCI-DSS and SOC 2 requirements.
• • Continuously learn and share: attend ClueCon, Kamailio World, and virtual VoIP meetups; publish blog posts and internal tech talks that keep Telnyx at the forefront of real-time communications innovation.