Made withSlateHut

Available for freelance & full-time — Kolkata, India (IST)

10 Years. One Stack. Endless Possibilities.

Senior Full-Stack Engineer specialising in Node.js · React · Next.js — architecting fast, scalable, production-ready web systems since 2014.

Node.js APIs & Microservices

High-throughput REST & GraphQL backends built for scale.

React & Next.js Front-Ends

SSR, ISR, edge-ready UIs with pixel-perfect design systems.

TypeScript-First Architecture

Type-safe, maintainable codebases that teams love to extend.

Trusted by startups & agencies across India, the UK, and the US

A decade of shipping software that matters.

Years of Experience
10+
Projects Delivered
80+
Happy Clients
15+
Open-Source Packages
3

From Kolkata With Code

The story behind the engineer.

Sandeep Acharya — Full-Stack Engineer portrait

Feature 01

Roots in Kolkata, Reach Across the World

I started writing Node.js scripts in a cramped apartment in Kolkata back in 2014 — fascinated by the idea that a single JavaScript runtime could power both a sleek front-end and a battle-tested back-end. Ten years later, that curiosity has become a career. I've worked with early-stage startups, mid-size agencies, and enterprise teams across India, the UK, and North America — always remotely, always asynchronously, always on time.

Code architecture diagram on a monitor

Feature 02

From Junior Dev to Architect-Level Engineer

My progression wasn't linear — it was deliberate. I moved from writing jQuery spaghetti to building type-safe React component libraries. From monolithic Express apps to event-driven microservices with RabbitMQ and Redis. Each project taught me that the best code isn't just code that works — it's code that the next engineer can read at 2 AM without crying. That philosophy drives every PR I open.

Clean code on a modern IDE

Feature 03

Clean Code. Scalable Systems. Zero Drama.

I believe software should be boring in the best possible way — predictable, observable, and easy to change. I write tests before I ship. I document APIs before I push. I open PRs that reviewers want to approve. Whether it's a greenfield SaaS product or a performance overhaul of a legacy monolith, I bring the same rigour: clear communication, realistic timelines, and code you'll be proud of in two years.

The Stack I Live In

Server infrastructure

Node.js

RESTful & GraphQL APIs, microservices with event queues (RabbitMQ, Redis Pub/Sub), real-time features via Socket.io — built to handle millions of requests.

React

Complex SPAs, design systems, Context + Zustand state management, performance budgets, and WCAG-compliant component libraries.

Next.js

SSR, ISR, App Router, edge middleware, image optimisation, and Lighthouse 100 scores — the full Next.js playbook.

TypeScript

Strict mode. Generics. Utility types. Discriminated unions. Type-safe codebases that scale across teams without type-any shortcuts.

PostgreSQL & MongoDB

Relational schema design, query optimisation, indexing strategies, aggregation pipelines, and Prisma/Mongoose ORM layers.

DevOps pipeline visualisation

DevOps & CI/CD

Docker, GitHub Actions, Vercel, AWS EC2/S3/Lambda, zero-downtime deploys, environment parity, and structured logging with Datadog.

What I Build

From idea to deployment — here's where I add the most value.

01

Web Applications

Full-stack React + Node.js apps with real-time capabilities, authentication, and cloud deployment — built to grow.

02

API Platforms

Versioned REST & GraphQL APIs with OpenAPI docs, rate limiting, JWT auth, and webhook systems your partners will love integrating.

03

E-Commerce Solutions

Custom storefronts on Next.js with headless Shopify or Stripe Checkout — fast, SEO-optimised, and conversion-focused.

04

SaaS Products

Multi-tenant architectures, subscription billing, role-based access control, and onboarding flows — the full SaaS foundation.

05

Performance Audits

Lighthouse audits, Core Web Vitals triage, database query profiling, and bundle analysis — I find the bottlenecks and fix them.

06

Technical Consulting

Architecture reviews, tech-stack decisions, code reviews, and mentoring for your in-house team — strategic advice when you need it most.

10 Years in the Making

The

Junior Node.js Developer

First professional role at a Kolkata-based agency — building REST APIs with Express.js and learning the hard lessons about production databases.

Fro

React & Redux Specialist

Fell headfirst into the React ecosystem. Built complex SPAs for fintech and ed-tech clients. Discovered the power of a well-designed component library.

Goi

Senior Full-Stack Engineer

Led a team of 4 engineers building a multi-tenant SaaS platform from scratch — microservices, Docker, AWS, CI/CD pipelines. First taste of architecture ownership.

Nex

Next.js Architect & Independent Contractor

Went independent. Adopted Next.js as primary framework. Delivered SSR-first projects for clients in the UK and US with measurable SEO and performance gains.

Tod

Senior Full-Stack Engineer & Consultant

Partnering with startups and agencies as lead engineer or fractional CTO — architecting systems, shipping code, and raising the bar for engineering culture.

What Clients Say

Sandeep delivered our entire API platform in six weeks — on spec, on budget, and with documentation so thorough our in-house team could immediately extend it. Genuinely one of the best engineers I've worked with in 12 years of building software products.

James Whitfield

CTO, Velocita Labs (London, UK) · Velocita Labs

We hired Sandeep for a 'quick performance audit' and he ended up cutting our page load time by 68% and our cloud bill by 40%. His knowledge of Next.js internals and database optimisation is exceptional. He communicates clearly, works independently, and never misses a deadline.

Priya Mehta

Product Lead, FinTrack India · FinTrack India

Working across time zones with a remote engineer can be nerve-wracking — not with Sandeep. His async communication is impeccable. He asks the right questions upfront, then executes with precision. The React design system he built for us is now used across three products.

Rachel Torres

Founder, NovaSpark Studio (Austin, TX) · NovaSpark Studio

Why Hire a Senior Engineer vs. a Generic Agency?

Communication

Sandeep Acharya
Direct, async-first, always accountable
Generic Dev Agency
Account managers & ticket queues

Code Ownership

Sandeep Acharya
You get clean, documented, maintainable code
Generic Dev Agency
Black-box delivery, hard to extend

Response Time

Sandeep Acharya
Same-day on business days (IST)
Generic Dev Agency
48–72 hour SLA on queries

Stack Depth

Sandeep Acharya
10 years in Node / React / Next.js — nothing surface-level
Generic Dev Agency
Generalists rotated between projects

Pricing

Sandeep Acharya
Transparent flat-rate or retainer
Generic Dev Agency
Opaque hourly billing with surprises

Transparent Pricing

No hidden fees. No scope creep surprises. Just honest, professional engineering.

Plan 01

Freelance Project

Custom Quoteper project

  • Fixed scope & fixed price — no surprises
  • Detailed technical spec before work starts
  • Weekly progress updates & demo calls
  • Handover with full documentation
  • 30 days post-launch bug-fix warranty
  • Ideal for: MVPs, new features, audits
Get a Quote
Popular
Plan 02

Monthly Retainer

₹1,20,000per month

  • 80 dedicated hours per month
  • Ongoing feature development & maintenance
  • Priority Slack / async communication
  • Weekly syncs & sprint planning
  • Architecture reviews & code mentoring
  • Ideal for: Growing startups, product teams
Start Retainer
Plan 03

Consulting

₹8,000per hour

  • Architecture & tech-stack advisory
  • Code & security review sessions
  • Hiring interviews & technical assessments
  • Performance triage & incident support
  • Session notes & action items provided
  • Ideal for: CTOs, tech leads, founders
Book a Session

Frequently Asked Questions

What time zone do you work in? Can we have overlapping hours?
I'm based in Kolkata, India (IST, UTC+5:30) and work standard business hours. I can flex morning or evening slots to overlap with UK afternoons or US East Coast mornings — just mention your preference when you reach out.
Do you work with non-technical founders?
Absolutely. A big part of my role is translating technical complexity into plain language. I'll help you understand trade-offs, set realistic expectations, and make smart decisions without needing to know what a REST API is.
How do you handle project scope changes?
Scope changes are a reality of product development. For fixed-price projects I document a change-request process upfront — any additions are scoped, priced, and approved before work begins. No surprise invoices.
Can I see examples of your previous work?
Most client work is under NDA, but I can share anonymised case studies, walk you through architecture decisions, and point you to my public open-source projects on GitHub. Let's chat and I'll share what's relevant to your project.
Do you work with teams or only solo?
Both. I can be your sole engineer on a greenfield project, or embed as a senior IC into an existing engineering team, or operate as a fractional CTO advising your team. I adapt to what you need.
What's your availability right now?
I typically have 1–2 project slots open each quarter. The best way to check and reserve time is to send me a message via the contact form below — I respond to all serious enquiries within 24 hours.
Node.jsReactNext.jsTypeScriptPostgreSQLMongoDBDockerAWSGitHub ActionsRedisVercelJWT & AuthNode.jsReactNext.jsTypeScriptPostgreSQLMongoDBDockerAWSGitHub ActionsRedisVercelJWT & Auth

Let's Build Something Great.

I'm available for freelance projects, monthly retainers, and consulting engagements. Based in Kolkata (IST) — responsive within 24 hours. Drop me a message and let's talk about what you're building.

Project Enquiry

Fill in the form below and I'll get back to you within 24 hours (IST, Monday–Friday). The more detail you share about your project, the more useful my first response will be.