Telephony Engineer FreeSWITCH, VoIP - optimhire

Roles & Responsibilities

We are looking for a FreeSWITCH Implementation Engineer who will be responsible for

designing, deploying, configuring, integrating, and maintaining FreeSWITCH-based

VoIP platforms. The role involves working closely with SIP, RTP, WebRTC, IVR,

conferencing, call routing, and external integrations in a production environment.

�� Key Responsibilities

�� FreeSWITCH Core Responsibilities

 Install, configure, and maintain FreeSWITCH in production environments from the

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, registration failures

 Configure NAT traversal, firewall rules, and RTP port ranges

 Analyze SIP logs and traces (siptrace, sngrep, tcpdump)

�� Dialplan & Scripting

 Develop dialplans using:

o XML

o Lua / JavaScript / Python

 Implement logic for:

o Call queues for inbound and outbound calls

o Time-based routing

o Skill-based routing

o Failover and fallback handling

�� Integrations & APIs

 Integrate FreeSWITCH with:

o CRM / ERP systems

o Billing platforms

o AI voice bots (ASR/TTS)

o External WebSocket or REST services

 Use Event Socket Library (ESL):

o Inbound & Outbound ESL

o Real-time call control and monitoring

�� WebRTC & Media

 Configure WebRTC support (DTLS-SRTP, ICE, OPUS)

 Work with mod_verto, SIP over WSS

 Implement browser-based calling solutions

�� Monitoring & Debugging

 Monitor system performance and call quality

 Analyze logs and CDRs

 Optimize codec usage and RTP performance

 Handle live production incidents and RCA

�� Deployment & Operations

 Deploy FreeSWITCH on:

o Linux (CentOS / Ubuntu)

o Cloud platforms (AWS / GCP / Azure – preferred)

 Configure HA, load balancing, and scaling

 Work with DevOps teams for CI/CD, backups, and automation

Ideal Candidate

1Strong FreeSWITCH Implementation Engineer Profiles

Mandatory (Experience 1) – Must have minimum 4+ years experience, with at least 3+ years of hands-on experience implementing, configuring, and supporting FreeSWITCH in production environments.

Mandatory (Experience 2) – Must have strong experience in designing and implementing FreeSWITCH call flows, including dialplans, IVRs, call routing, conferencing, SIP profiles, gateways, trunks, and extensions with end-to-end ownership.