Senior Development Engineer

Job Title: Telecom Development Engineer – FreeSWITCH & Kazoo
Department: Engineering / VoIP Platform
Location: On-Site Delhi
Employment Type: Full-time
Experience Level: 5+ years in VoIP/Telecom Development

Role Summary:

We are seeking a highly skilled Telecom Development Engineer with hands-on experience in FreeSWITCH and Kazoo, alongside strong programming skills in Go, Python, and familiarity with Cloud Databases, RabbitMQ, REST APIs, Ansible, Prometheus, Grafana, and Git

The ideal candidate will be responsible for developing and maintaining VoIP applications and modules in FreeSWITCH and integrating them into the Kazoo multi-tenant telephony platform using Monster UI.

Key Responsibilities:

Design and Develop Custom FreeSWITCH Modules:

• Create scalable, high-performance modules and dialplans in FreeSWITCH using Lua, Go, or C.
• Work with ESL (Event Socket Library) and mod_xml_curl to extend call handling logic
• Kazoo Integration and Configuration:
• Deploy FreeSWITCH modules and services into Kazoo via Monster UI and Kazoo APIs.
• Customize and extend Kazoo applications using Kazoo’s AMQP and REST API interfaces.
• Application Development:
• Build automation tools and microservices using Go and Python to manage telecom workflows.
• Develop backend services that interface with SIP, RTP, and Kazoo/FreeSWITCH subsystems.
• Infrastructure Automation & Monitoring:
• Automate deployments with Ansible.
• Monitor system health using Prometheus and Grafana.
• Implement scalable logging, alerting, and system health-checks.
• DevOps & Source Control:
• Use Git for version control and CI/CD workflows.
• Collaborate on code reviews and participate in agile sprints.
• API Integration:
• Consume and expose RESTful APIs to support user interface functionality and backend logic.
• Integrate with third-party systems and internal services using RabbitMQ message queues.
• Troubleshooting and Optimization:
• Investigate and resolve SIP signaling issues, one-way audio, NAT traversal, and codec mismatches.
• Optimize RTP stream handling, failover, load balancing, and call quality.

Required Skills & Qualifications:

• VoIP Expertise:
• Deep understanding of SIP, RTP, SDP, NAT, and SIP tracing tools (e.g., sngrep, Wireshark).
• Experience building and maintaining VoIP platforms using FreeSWITCH and Kazoo.
• Programming Languages:
• Proficiency in Go (Golang) and Python.
• Familiarity with Lua scripting and C for FreeSWITCH module development.
• Messaging & Databases:
• Experience with RabbitMQ (AMQP) and Cloud DBs like CouchDB/Couchbase (used by Kazoo).
• Infrastructure Tools:
• Strong skills in Ansible, Git, and CI/CD pipelines.
• Proficient in Prometheus and Grafana for system observability.
• Web & API Skills:
• Proficient in designing and consuming RESTful APIs.
• Experience with Kazoo REST APIs and Monster UI for provisioning and monitoring.

Preferred Qualifications:

• Experience working in multi-tenant VoIP platforms.
• Familiarity with WebRTC, STUN/TURN, and SBCs (Session Border Controllers).
• Previous contributions to open-source VoIP projects.
• Knowledge of Docker or containerization for telecom applications.

Key Attributes:

• Strong problem-solving skills and ability to work independently.
• Excellent communication and documentation skills.
• Passion for scalable systems, performance optimization, and clean architecture.
• Collaborative mindset and proactive in a team environment.

Job Types: Full-time, Permanent

Pay: ₹311,015.97 - ₹900,000.00 per year

Benefits:

• Cell phone reimbursement
• Internet reimbursement
• Paid time off

Work Location: In person

Expected Start Date: 11/08/2025