FreeSWITCH Implementation Engineer

Roles & Responsibilities :

We are looking for a FreeSWITCH Implementation Engineer responsible for designing, deploying, configuring, integrating, and maintaining FreeSWITCH-based VoIP platforms. The role involves working extensively with SIP, RTP, WebRTC, IVR, conferencing, call routing, and external integrations in production environments.

Key Responsibilities :

FreeSWITCH Core Responsibilities :

- Install, configure, and maintain FreeSWITCH in production environments from scratch.

- Design and implement call flows, dialplans, IVRs, conferencing, and call routing with complete ownership.

- Configure SIP profiles (internal/external), gateways, trunks, and extensions.

- Implement multi-tenant and high-availability FreeSWITCH architectures.

SIP, RTP & Networking :

- Strong understanding of SIP signaling, RTP media, and SDP negotiation.

- Troubleshoot one-way audio, no-audio, call drops, and registration failures.

- Configure NAT traversal, firewall rules, and RTP port ranges.

- Analyze SIP logs and traces using siptrace, sngrep, and tcpdump.

Dialplan & Scripting :

- Develop FreeSWITCH dialplans using XML and at least one scripting language such as Lua, JavaScript, or Python.

- Implement call queues for inbound and outbound calls, time-based routing, skill-based routing, failover, and fallback handling.

Integrations & APIs :

- Integrate FreeSWITCH with CRM/ERP systems, billing platforms, AI voice bots (ASR/TTS), and external WebSocket or REST services.

- Use Event Socket Library (ESL), including inbound and outbound ESL, for real-time call control and monitoring.

WebRTC & Media :

- Configure WebRTC support including DTLS-SRTP, ICE, and OPUS.

- Work with mod_verto and SIP over WSS.

- Implement browser-based calling solutions.

Monitoring & Debugging :

- Monitor system performance and call quality, analyze logs and CDRs, and optimize codec usage and RTP performance.

- Handle live production incidents and conduct root cause analysis (RCA).

Deployment & Operations :

- Deploy FreeSWITCH on Linux environments including CentOS and Ubuntu.

- Deploy and manage FreeSWITCH on cloud platforms such as AWS, GCP, and Azure.

- Configure high availability, load balancing, and scaling.

- Work with DevOps teams on CI/CD, backups, and automation.

Ideal Candidate :

- Strong FreeSWITCH Implementation Engineer profile.

- Minimum 4+ years of overall experience, with at least 3+ years of hands-on experience implementing, configuring, and supporting FreeSWITCH in production environments.

- Strong experience designing and implementing FreeSWITCH call flows, including dialplans, IVRs, call routing, conferencing, SIP profiles, gateways, trunks, and extensions, with end-to-end ownership.

- Strong hands-on knowledge of VoIP technologies including SIP, RTP, RTCP, SDP, and WebRTC, with the ability to troubleshoot call drops, one-way audio, registration failures, NAT traversal, and SIP/RTP-related issues.

- Hands-on experience developing FreeSWITCH dialplans using XML and at least one scripting language such as Lua, JavaScript, or Python, including call queues, time-based routing, skill-based routing, and failover logic.

- Experience integrating FreeSWITCH with CRM/ERP systems, REST APIs, WebSockets, AI Voice Bots (ASR/TTS), or Billing Platforms, along with hands-on experience using Event Socket Library (ESL) for real-time call control.

- Strong Linux administration experience with the ability to deploy and manage FreeSWITCH on Ubuntu/CentOS, along with debugging expertise using fs_cli, sngrep, and tcpdump, and working knowledge of SQL (MySQL/PostgreSQL) for CDRs and reporting.

- Experience with AWS, Azure, or GCP, High Availability (HA), Load Balancing, CI/CD pipelines, automation, backups, and scalable FreeSWITCH deployments.

- Experience implementing WebRTC-based calling solutions, including mod_verto, SIP over WSS, DTLS-SRTP, ICE, and OPUS codec configuration.

Skills

FreeSWITCH, VoIP, SIP, RTP, WebRTC, Telecom