Role Responsibilities

We are looking for a Full Stack Developer who can build and maintain web applications, work comfortably with real-time voice and messaging infrastructure, and use modern AI tools to ship faster. You will work across our customer portal, internal admin tools, AI-assisted calling features, and the APIs that connect them to our VoIP switching, SMS, and billing systems. This is a hands-on role suited to someone who enjoys both application development and understanding what happens on the wire during a call.

Key Responsibilities

. Design, build, and maintain backend services in Python (FastAPI / Django / Flask) that power calling, messaging, and billing features.

. Build responsive frontend interfaces (React / Vue / modern JavaScript) for customer dashboards and internal tools.

. Develop and maintain REST APIs and webhooks consumed by customers and internal systems.

. Integrate with VoIP platforms — FreeSWITCH / Asterisk / Kamailio — via ESL, AMI, or API for call control, routing, and provisioning.

. Work with SIP signalling and media flows; troubleshoot call failures using SIP traces, CDRs, and logs.

. Integrate SMS/messaging flows over SMPP or HTTP APIs.

. Build AI-powered features into the platform: call transcription, call summaries, sentiment analysis, chat/voice bots, and agent-assist tools using LLM APIs. . Build CDR processing, rating, and reporting pipelines feeding the billing system.

. Write database schemas and efficient queries (PostgreSQL / MySQL), and use Redis for caching and queues.

. Use AI coding assistants responsibly to accelerate development, while owning correctness, security, and code review.

. Participate in code reviews, write tests, and support CI/CD deployment.

. Work with the NOC/support team on production issues affecting live traffic.

Required skills

Programming & Web - 3+ years of professional Python development. - Strong experience with at least one Python web framework (FastAPI, Django, or Flask). - Frontend proficiency: JavaScript/TypeScript, HTML,



CSS, and a modern framework (React preferred). - REST API design, authentication (JWT/OAuth2), and third-party API integration. - SQL databases (PostgreSQL/MySQL) — schema design, indexing, query tuning. - Git, Linux command line, Docker.

AI / LLM - Practical experience integrating LLM APIs — Anthropic Claude, OpenAI, or similar — into production applications. - Comfortable with prompt design, structured/JSON outputs, streaming responses, token and cost management. - Day-to-day use of AI coding assistants (Claude Code, Cursor, GitHub Copilot) with positive judgement about reviewing and testing generated code. - Understanding of embeddings, vector search, and RAG (retrieval-augmented generation) at a working level.

VoIP / Telecom - Working knowledge of SIP (INVITE, registration, call flow, common response codes). - Hands-on exposure to FreeSWITCH, Asterisk, or Kamailio — dialplan, routing, or API-level integration. - Understanding of RTP/media, codecs (G.711, G.729, Opus), and NAT traversal basics. - Familiarity with CDRs, call routing logic, DIDs, and trunk/carrier concepts. - Ability to read SIP traces (sngrep, Wireshark, HOMER) for basic troubleshooting.

Good to have

. AI voice agents — STT/TTS integration (Deepgram, Whisper, ElevenLabs), real-time voice pipelines, barge-in handling.

. Agent frameworks, function/tool calling, MCP, or workflow automation with LLMs.

. SBC exposure (Kamailio, OpenSIPS, Oracle/Ribbon).

.SMPP / SMS gateway integration experience.

. WebRTC and browser-based softphone development.

. Knowledge of STIR/SHAKEN, CNAM, number portability, or regulatory/compliance workflows. Experience with UCaaS/CCaaS or wholesale carrier platforms.

. Message queues (RabbitMQ, Kafka, Celery).

. Cloud infrastructure (AWS/GCP), Kubernetes, monitoring (Prometheus/Grafana).

Qualification

. Bachelor's degree in Computer Science, IT, Electronics/Telecommunications, or equivalent practical experience.

. Good written and spoken English. Willingness to occasionally support production escalations outside business hours.

📌 Python Developer (Mumbai)
🏢 Swadesh Mobile Private
📍 Mumbai