MERN Stack Developer

About the Role

We are hiring a highly skilled Senior Backend Node.js Developer who can build, optimize, and scale the backend infrastructure of Sarv’s Deepcall — a high-performance cloud telephony & omnichannel communication platform.

This role needs someone with deep backend fundamentals, experience with high-volume systems, real-time events, distributed queues, microservices, and data streaming.

You will be working with Node.js, Elasticsearch, MongoDB, Redis, RabbitMQ/Kafka, WebSockets, IPC, and custom telephony modules.

Key Responsibilities

Backend Development & Architecture

● Design and develop scalable backend services using Node.js.

● Build microservices for telephony, call routing, ACD, WebRTC signaling, IVR workflows, message queues, and real-time events.

● Implement RESTful APIs, WebSocket-based services, and internal service-to-service communication.

Real-Time Processing (Telephony)

● Work on telephony-related modules:

○ Call logs flow

○ ACD engine

○ WebRTC signaling

○ Real-time call events

○ Agent state transitions

○ Event-driven routing systems

● Optimize latency and concurrency for real-time voice systems.

Data Handling & Optimization

● Build and optimize Elasticsearch queries (aggregation, nested, scroll, bulk, time-series handling).

● Work with MongoDB for high-volume document operations.

● Implement caching layers using Redis, TTL strategies, and pub/sub patterns.

● Handle millions of records efficiently with optimized indexing & data models.

Queues, Streaming & Event-Driven Architecture

● Implement and manage high-throughput queues using RabbitMQ or Kafka.

● Build producers/consumers for telephony workflows (call events, call states, CDR processing, agent events).

Interprocess Communication (IPC) & System Programming

● Implement multi-process Node.js apps (cluster mode, worker threads, child processes).

● Strong hold on OS concepts: file descriptors, sockets, event loops, buffers, concurrency models.

● Write efficient socket-based programs for internal signaling.

Performance, Reliability & Scalability

● Optimize code for low latency & high throughput.

● Build retry handling, persistence queues, circuit breakers, and fail-safe mechanisms.

● Work on large-scale log processing pipelines.

Telephony Domain Responsibilities

● Understand call flows, SIP/WebRTC basics (optional but preferred).

● Work on modules like call routing, IVR, call state machine, events pipeline.

● Collaborate with telephony/VoIP teams for API integrations.

Monitoring, Debugging & DevOps Collaboration

● Work with DevOps for CI/CD, scaling microservices, and containerization (Docker).

Required Skills & Qualifications

Core Technical Skills

● Node.js (3+ years) with strong fundamentals (events, async, memory, cluster, streams).

● Elasticsearch (indexing, nested fields, aggregations, time-series queries).

● MongoDB (schema design, indexing, pipelines).

● Redis (cache, pub/sub, streams).

● RabbitMQ / Kafka (message queues, routing, consumer groups).

● WebSockets & real-time event systems.

● IPC, socket programming, networking basics.

● Excellent command over algorithms, patterns, data structures, and backend architecture.

Must-Have Knowledge Areas

● Event-driven systems.

● API performance optimization.

● Large-scale data handling.

● Fault-tolerant distributed systems.

● High-concurrency systems.

● Memory management and Node.js internals.

● Working with large JSON data, micro-batching, and queue-based processing.

Good to Have / Preferred

● Experience with Telephony: SIP, RTP, WebRTC signaling, Asterisk/Freeswitch basics.

● Knowledge of microservices architecture & containerization (Docker).

● Experience in building SaaS or CPaaS platforms.

● Exposure to distributed locks, rate-limiting, throttling strategies.

Soft Skills

● Strong ownership & accountability.

● Ability to break complex problems into clean, modular solutions.

● Clear communication and ability to work with product, QA, telephony & infra teams.

● Debugging mindset—can trace issues across distributed systems.