Hire NestJS Developers

Expert VoIP backend APIs, SIP signalling servers, and microservices. Build scalable communication infrastructure.

$25/hr

Starting Rate

48 hrs

Onboarding

Top 3%

Vetted Talent

30 days

Money Back

What You Get

Expert NestJS 10 + TypeScript

REST/GraphQL API design

FreeSWITCH ESL integration

Microservices architecture

CDR processing at scale

Production deployment focus

Technology Stack

NestJS Core

NestJS 10

TypeScript strict

Dependency Injection

Decorators

Modules

API Layer

REST with Swagger

GraphQL (Apollo)

tRPC

gRPC

WebSockets (Socket.io)

Database & ORM

PostgreSQL + Prisma

MongoDB + Mongoose

Redis

TypeORM

Drizzle ORM

VoIP Integration

FreeSWITCH ESL (modesl)

Asterisk AMI

SIP signalling APIs

CDR processing

WebRTC signalling

Messaging & Events

Kafka

RabbitMQ

BullMQ jobs

NestJS EventEmitter

CQRS pattern

Auth & Security

JWT/OAuth2

Passport.js

RBAC guards

API rate limiting

Helmet security

Developer Roles Available

Senior NestJS Backend Developer

$25/hr

NestJS, TypeScript, REST/GraphQL, PostgreSQL, Prisma, Redis, Docker

Architecture-focused backend engineer with production deployment experience

NestJS VoIP / SIP API Developer

$30/hr

FreeSWITCH ESL, Asterisk AMI, SIP gateway APIs, CDR processing, NestJS WebSocket

Specialized in real-time VoIP backend integration

NestJS Microservices Developer

$28/hr

NestJS microservices, Kafka, RabbitMQ, gRPC, distributed systems, event sourcing

Expert in high-throughput event-driven telecom architectures

NestJS + React Full-Stack Developer

$28/hr

NestJS API backend, React/Next.js frontend, tRPC, JWT auth, Stripe billing

Full-stack capability with backend excellence

Common Use Cases

VoIP Platform REST API

Comprehensive SIP user management, DID provisioning, trunk configuration, and CDR API

FreeSWITCH ESL Event Server

NestJS service consuming FreeSWITCH events for real-time call control and CDR storage

Real-Time Billing Engine

CDR ingestion, LCR rating, prepaid balance deduction with sub-100ms rating per call

SIP Trunk Provisioning API

REST API for carrier trunk management, failover routing, and capacity management

WebRTC Signalling Server

NestJS WebSocket signalling for browser-based calling — offer/answer/ICE exchange

Microservices VoIP Platform

Distributed platform with separate NestJS services for routing, billing, users, and analytics

How We Compare

Provider	Rate	Expertise	Onboarding
CelloIP	$25-30/hr	NestJS + VoIP vetting	48hrs
Toptal	$90-180/hr	General Node.js	2-3 weeks
Upwork	$15-60/hr	Self-reported skills	1-5 days
Clutch Agencies	$80-150/hr	Agency-managed	2-4 weeks
Fiverr Pro	$15-50/hr	Portfolio-based	1-3 days

Our Hiring Process

Requirements

Describe your NestJS backend or VoIP API needs

Match Developer

We find the right NestJS specialist for your project

Code Challenge

Live NestJS API development and TypeScript test

Trial Project

2-week trial on actual work with refund guarantee

Deploy Ready

Fully productive and integrated within 48 hours

Our Guarantees

30-Day Refund

Full refund if not satisfied

48-Hour Onboarding

Productive immediately

Top 3% Vetted

Expert NestJS developers

24-Hour Swap

Instant replacement if needed

What Clients Say

"Our NestJS billing API processes 2M+ CDRs daily with real-time LCR rating. The developer designed the Kafka pipeline, Prisma schema, and rate limiting module. Production has been flawless for 8 months."

Lars Eriksson

NordicVoIP

"FreeSWITCH ESL integration in NestJS was complex — the developer delivered a clean module with full event subscription, call state tracking, and Redis-backed session store. Outstanding architecture."

Natasha Ivanova

TeleOps Platform

"NestJS microservices for our CPaaS — routing, billing, users, and analytics as separate services. The developer handled Kafka messaging, gRPC contracts, and Docker compose perfectly."

Marco Ferreira

VoiceStack SaaS

Frequently Asked Questions

Why use NestJS for a VoIP backend?

NestJS provides a structured, opinionated TypeScript framework with built-in dependency injection, decorators for routing and validation, and modular architecture — ideal for VoIP platforms where call control, billing, CDR processing, and user management each need clean module boundaries. It integrates natively with Socket.io for WebSocket-based AMI/ESL interfaces.

Can NestJS connect to FreeSWITCH ESL?

Yes. We use the modesl library or a custom TCP socket module in NestJS to connect to FreeSWITCH's Event Socket Layer. NestJS's module system isolates the ESL connection cleanly, and its event emitter allows other modules to subscribe to call events without tight coupling.

NestJS vs Express for a SIP API server?

NestJS is strongly preferred for complex VoIP backends: built-in validation pipes, guards for auth, interceptors for CDR logging, and OpenAPI/Swagger auto-generation. Express requires manually wiring all these. For simple single-route proxies, Express is fine; for production VoIP platforms, NestJS is the right choice.

How much does NestJS backend development cost?

A production NestJS VoIP backend API (user management, CDR, billing, SIP configuration) typically costs $10,000–$30,000. Our dedicated developers at $25–30/hr deliver the same quality as a US/EU agency at 50–70% lower cost.

Can NestJS handle high-throughput CDR processing?

Yes. NestJS with Kafka consumers and PostgreSQL (or ClickHouse for analytics) handles millions of CDRs per day. We use BullMQ for background rating jobs and Redis for in-flight prepaid balance management. We've built platforms handling 5M+ CDRs daily.

Does NestJS support WebRTC signalling?

Yes. NestJS's built-in WebSocket gateway (Socket.io or native ws) works perfectly for WebRTC signalling — handling offer/answer exchange and ICE candidate trickling. It pairs with STUN/TURN (coturn) for NAT traversal.

Other Specialized Roles

Node.js Backend

React.js Frontend

FreeSWITCH SIP Server

VoIP Infrastructure

NestJS Development Resources

Custom Software Development

Full-stack web & mobile development

FreeSWITCH ESL with Node.js Guide

Real-time call control via Event Socket

Building VoIP Backends with NestJS

SIP signalling and FreeSWITCH ESL integration

Hire Node.js Developers

Node.js backend & API specialists

Hire Next.js Developers

Next.js 15 App Router specialists

Hire React.js Developers

React + WebRTC dashboard engineers

Hire FreeSWITCH Developers

FreeSWITCH ESL & media server experts

Developer FAQs & Pricing

Rates, contracts, timelines answered

Ready to Build Your NestJS Backend?

Find your NestJS expert in 48 hours. 30-day money-back guarantee.