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:

1. XML

2. Lua / JavaScript / Python

- Implement logic for:

1. Call queues for inbound and outbound calls

2. Time-based routing

3. Skill-based routing

4. Failover and fallback handling

Integrations & APIs :

- Integrate FreeSWITCH with:

1. CRM / ERP systems

2. Billing platforms

3. AI voice bots (ASR/TTS)

4. External WebSocket or REST services

- Use Event Socket Library (ESL):

1. Inbound & Outbound ESL

2. 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:

1. Linux (CentOS / Ubuntu)

2. Cloud platforms (AWS / GCP / Azure preferred)

- Configure HA, load balancing, and scaling.

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

Requirements :

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

- 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.

- Must have strong hands-on knowledge of VoIP technologies, including SIP, RTP, RTCP, SDP, WebRTC, and should be capable of troubleshooting call drops, one-way audio, registration failures, NAT traversal, and SIP/RTP-related issues.

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

- Must have 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.

- Must have strong Linux administration experience and should be comfortable deploying and managing FreeSWITCH on Ubuntu/CentOS, along with debugging using fs_cli, sngrep, tcpdump, and working with SQL (MySQL/PostgreSQL) for CDRs and reporting.

- Immediate Joiners or candidates who can join within 15 days will be highly preferred.

- Mandatory (Location) Candidate must be currently based in Delhi NCR only.