Delhi, India · Available worldwide, remote-first

Best Node.js Developer — Building Fast, Secure Distributed Systems

Sachin Sharma is a top Node.js developer based in Delhi, India, specializing in high-concurrency backend services, REST/GraphQL APIs, and serverless edge functions. With professional experience at ESPO and Kushal Aide, Sachin designs modular backend architectures utilizing Express, NestJS, and Fastify, backed by PostgreSQL, Redis, and Docker.

I know you want to build something great with Node.js Development.

There are 10 lakh+ agencies, 5 crore+ "vibe coders," and 1 crore+ developers out there — and somehow you ended up on this page. That's not an accident, that's a genuine signal. I'm 21, and if you're on my website right now, you're already looking at someone better than most of what's out there. I'd genuinely prefer to talk to you directly rather than have you read through another page. Please feel free to call, message, or email — whichever works best for you.

Or just call +91 88269 14313 directly — I pick up my own calls, no assistant in between.

Or just see what I've built first

At a Glance

Runtime Environment

Node.js LTS (V8 Engine Optimization)

API Frameworks

Fastify (High throughput), Express, NestJS (Modular)

Asynchronous Control

Promises, Async/Await, EventEmitter, Streams

Multi-Threading

Worker Threads API, Cluster Module, Child Processes

Relational Databases

PostgreSQL (with PgPool optimization), SQLite

Caching & Sessions

Redis (In-memory storage & pub-sub)

Containerization

Multi-stage Docker builds, Kubernetes routing

APM Tools

Clinic.js, Clinic Bubbleprof, Prometheus, Grafana

On This Page

~9 min read

1. The V8 Event Loop & Non-Blocking Asynchronous I/O

2. Memory Diagnostics: Closure Leaks & Heap Profiling

3. The Runtime Battle: Node.js vs Deno vs Bun in 2026

4. API Scale: Express, Fastify, and NestJS Architectures

5. Database Integrations: Connection Pools & Transaction Isolations

6. Multi-Threaded Processing (Worker Threads & Cluster)

7. Case Study: Scaling System Backend at ESPO

Sachin Sharma vs. Alternatives

How working with me directly compares to agencies and general freelancers.

Metric	Sachin Sharma	Agencies	Freelancers
Who you talk to	Me, directly. The person writing your code answers your messages.	Account managers and PMs relay your feedback to developers you never meet.	Variable — depends who you find, timezone gaps are common.
What you get	Production apps built end-to-end, not prototypes or tutorial-grade demos.	Junior developers rotated onto your project; senior oversight is inconsistent.	Often strong at scripts and one-off scripts, less so at shipping to production.
Performance work	Real optimization: shader precompilation for 60fps Flutter, Edge SSR under 50ms TTFB, bundle budgets enforced.	Standard boilerplate setup, rarely tuned past 'it works'.	Performance tuning usually skipped unless explicitly (and separately) paid for.
Code ownership	Fully typed, documented codebase. Full git history handed over on day one.	IP clauses and handover friction are common.	Documentation and typing discipline vary a lot person to person.

Frequently Asked Questions

How do you prevent event loop blocking in Node.js applications?

I offload CPU-intensive tasks (like file compression or crypto) to background worker threads, utilize streams for large payloads, and avoid synchronous filesystem operations.

What is Fastify and how does it compare to Express?

Fastify is a highly performant backend framework. It provides schema-based routing and optimized JSON serialization, handling up to 2x more requests per second than Express.

How do you manage database connection pooling in serverless environments?

In serverless runtimes, I use database connection pooling proxies (such as PgBouncer or Neon Postgres Serverless) to manage client connections and prevent database overload.

How do you secure Node.js applications against SQL injection?

I use query builders or ORMs (like Drizzle or Prisma) that compile queries using parameterized variables, preventing SQL injection attempts.

What is your approach to handling error logs in Node.js?

I structure errors using pino logging, capture stack traces via Sentry, and forward alerts to dashboard consoles for diagnostic analysis.

What is the difference between spawn, fork, and exec in Node?

`spawn` runs commands in a new process streaming their data, `exec` runs commands buffering their outputs, and `fork` spawns a new Node instance with built-in communication channels.

How do you trace memory leaks in a running Node.js server?

I run the process with `--inspect` flags, connect Chrome DevTools, capture heap snapshots at different times, and analyze retained allocations.

What is the Cluster module and how does it scale applications?

The Cluster module forks a master process across CPU cores. The forks share server ports, distributing incoming HTTP requests using round-robin scheduling.

How do you handle API security and rate limiting?

I configure CORS headers, integrate helmet middleware, and set up rate limiting using memory or Redis stores.

What are Streams and when should they be configured?

Streams read and write data sequentially in chunks. I use streams for large file uploads and heavy database queries to keep heap usage low.

What is the difference between Node.js, Deno, and Bun in 2026?

Bun 1.2+ uses JavaScriptCore for sub-3ms cold starts and native execution. Deno 2.0+ focuses on out-of-the-box TypeScript support and secure runtimes. Node.js 22+ offers stable libraries and connection pool scaling.

How does Bun achieve high HTTP throughput compared to Node?

Bun implements its serve handler directly in Zig, avoiding JavaScript object serialization overhead, and reads files using direct OS system call protocols.

Which runtime should I use for serverless edge functions?

For serverless deployments requiring sub-5ms latency, Bun is recommended. For complex enterprise microservices, Node.js remains the industry standard.

How do you hire node js consultancy services in India?

When hiring a Node.js consultancy, verify their experience with V8 profiling tools (like Clinic.js), multi-threaded worker pools, and scalable database pooling. Sachin Sharma provides senior engineering consulting directly.

Do you offer node js experts services for Singapore companies?

Yes. As a Node.js specialist, I consult for international firms, including developers and startups in Singapore, aligning backend architectures with edge platforms like Cloudflare Pages.