Available for freelance projects

Karthik
Sundararajan

Senior Full-Stack, Mobile & Cloud Engineer

15+ years of shipping products that scale — from early-stage MVPs to enterprise-grade platforms. React, Next.js, Node.js, React Native & AWS.

15+

Years Experience

50+

Projects Delivered

3

Core Domains

About Me

Engineering that actually ships.

I'm Karthik Sundararajan, a senior software engineer with over 15 years of hands-on experience building full-stack web applications, mobile apps, and cloud infrastructure for businesses across industries.

I've worked with startups, mid-size companies, enterprises, and agencies — adapting to each team's pace and standards while bringing senior-level ownership to every project I take on.

What sets me apart isn't just technical depth — it's that I understand the product side too. I build systems that are maintainable, scalable, and aligned with business goals, not just code that works today.

Problem SolverClean ArchitectureAgile DeliveryRemote Ready
KS

Karthik Sundararajan

Senior Software Engineer

● Available for projects

🌐ExpertiseFull-Stack, Mobile, Cloud
📍LocationBengaluru, India
Experience15+ Years
🤝Open toFreelance & Contracts

What I Do

Services

From initial architecture to production deployment — I cover the full spectrum of modern software engineering.

Full-Stack Web Development

End-to-end web application development using React.js, Next.js, Node.js, and Express. From architecture to deployment — clean, maintainable code built to scale.

React.jsNext.jsNode.jsExpress.js

Mobile App Development

Cross-platform mobile apps using React Native that deliver native-like performance on both iOS and Android. Fast builds, great UX, single codebase.

React NativeiOSAndroidExpo

Cloud & DevOps

AWS infrastructure setup, CI/CD pipelines, containerization, and deployment automation. Reliable, secure, and cost-optimised cloud environments.

AWSDockerCI/CDLinux

Database Design & Optimisation

Schema design, query optimisation, and data modelling across relational and non-relational databases. Built for performance at any scale.

PostgreSQLMySQLMongoDB

API Development & Integration

RESTful and GraphQL API design, third-party integrations, authentication systems, and microservices architecture that teams love to work with.

RESTGraphQLOAuthJWT

Technical Consulting

Architecture reviews, tech stack decisions, code audits, and engineering mentorship. Bring senior perspective to your team without the overhead.

ArchitectureCode ReviewStrategy

Tools of the Trade

Tech Stack

A curated set of technologies I've used deeply over 15+ years — not a buzzword list.

Frontend

React.js95%
Next.js92%
TypeScript88%
Tailwind CSS90%

Backend

Node.js95%
Express.js93%
REST APIs96%
GraphQL82%

Mobile

React Native90%
Expo85%
iOS (via RN)84%
Android (via RN)84%

Databases

MongoDB90%
PostgreSQL88%
MySQL87%
Redis75%

Cloud & DevOps

AWS88%
Docker85%
CI/CD83%
Linux86%

Tools

Git / GitHub98%
VS Code98%
Postman95%
Figma (handoff)78%

Selected Work

Projects

A snapshot of complex, real-world products I've architected and shipped end-to-end.

01

Fixcent ERP

Enterprise Resource Planning

A comprehensive ERP system built for business operations management — covering inventory, finance, HR workflows, and real-time reporting dashboards. Designed for scale and reliability in enterprise environments.

Multi-module architecture
Role-based access control
Real-time dashboards
React.jsNode.jsPostgreSQLAWSREST API
02

Splendx E-Commerce

E-Commerce Platform

A full-featured e-commerce platform with product catalogue management, dynamic pricing, payment gateway integrations, order tracking, and a mobile-responsive storefront built for conversion.

Payment gateway integration
Mobile-first design
Admin dashboard
Next.jsNode.jsMongoDBReact NativeAWS
03

Logistics Platform

Logistics & Supply Chain

An end-to-end logistics management platform for tracking shipments, managing fleets, assigning delivery agents, and providing live route updates — built for high throughput and real-time data accuracy.

Real-time shipment tracking
Fleet management
Live route optimisation
React.jsExpress.jsMySQLAWSMaps API

More projects available on request — let's talk

Get In Touch

Let's build something great together.

Whether you have a project ready to kick off, need a senior engineer on your team, or just want to explore possibilities — I'd love to hear from you.

📍

Location

Bengaluru, India (Remote Worldwide)