Available for freelance — 2 slots open

I build scalable backend systems & APIs for startups

Helping startups reduce costs, scale faster, and ship reliable backend systems.

Node.jsTypeScriptAWSStripe
4+
Years Experience
3
Companies
Sumit Kumar
status
open_to_work: true
What I Offer

What I can do for you

I help startups build robust, scalable, and cost-effective backend solutions.

Build Scalable Backend APIs

  • REST APIs using Node.js & TypeScript
  • MongoDB / PostgreSQL
  • Clean architecture

Payment & Subscription Systems

  • Stripe integration
  • Subscription billing
  • Webhooks handling

Performance & Cost Reduction

  • Optimize slow APIs
  • Reduce AWS / AI costs
  • Auto-scaling systems
About Me

Engineering dependable systems

I'm a Senior Backend Engineer with expertise in building backend APIs and websites using modern technologies like .NET Core, PHP, Laravel, and NodeJS. I bring strong problem-solving skills and 4+ years of software development experience to every project.

Backend Development

Expert in building robust APIs and backend systems using NodeJS, .NET Core, and Laravel with focus on performance and scalability.

Database Design

Proficient in designing efficient database schemas, query optimization, and working with both SQL and NoSQL databases.

System Design

Proficient in designing scalable, reliable, and maintainable system architectures, with a strong understanding of microservices, API design, load balancing, caching strategies, and cloud infrastructure.

CI/CD Pipeline

Proficient in setting up and managing robust CI/CD pipelines, automating build, test, and deployment workflows using tools like GitHub Actions, Jenkins, and Docker, ensuring fast and reliable software delivery.

Performance Optimization

Specialized in analyzing and improving application performance, implementing caching strategies, and code optimization.

Generative AI

Specialized in building AI-powered solutions, fine-tuning generative models, and optimizing workflows for intelligent automation and content creation.

Career

Experience

4+ years of professional software development.

July 2025 - Present
Current

Senior Backend Engineer

SiliconStream Technology, India

Role & Responsibilities

Worked as a Backend Engineer, responsible for developing and maintaining robust API services. Also had the opportunity to lead a development team, providing technical expertise and leadership to ensure the successful delivery of scalable and high-quality software solutions. Played a key role in architecture planning, code reviews, and mentoring team members.

Soft Skills

Strong logical thinking and problem-solving skills. Demonstrated effective teamwork and leadership in collaborative environments.

NodeJS
NestJS
MySQL
Express.js
MongoDB
Git
AWS
CI/CD
Github Action
Sep 2024 - Jun 2025

Senior Backend Engineer

75way technologies, India

Role & Responsibilities

Worked as a Backend Engineer, responsible for developing and maintaining robust API services. Also had the opportunity to lead a development team, providing technical expertise and leadership to ensure the successful delivery of scalable and high-quality software solutions. Played a key role in architecture planning, code reviews, and mentoring team members.

Soft Skills

Strong logical thinking and problem-solving skills. Demonstrated effective teamwork and leadership in collaborative environments.

.NET Core
NodeJS
MySQL
Express.js
MongoDB
Git
AWS
Laravel
Feb 2022 - Sep 2024

Backend Developer

75way technologies, India

Role & Responsibilities

Worked as a Backend Developer, responsible for developing and maintaining robust API services.

Soft Skills

Strong logical thinking and problem-solving skills.

.NET Core
NodeJS
MySQL
Express.js
MongoDB
Git
AWS
Laravel
Feb 2021 - Feb 2022

Laravel Developer

Incomparable Technologies, India

Role & Responsibilities

Worked as a Full Stack Developer, responsible for handling end-to-end development. Actively contributed to both frontend and backend components based on project requirements, ensuring smooth integration and efficient functionality.

Soft Skills

Strong logical thinking and problem-solving ability. Excelled in collaborative environments, effectively contributing as a team player.

PHP
Laravel
MySQL
Git
Javascript
Ajax

Skills

Languages & Runtimes
JavaScriptTypeScriptNode.js
Frameworks
Express.jsNestJS.NET Core
Data
MySQLMongoDB
Cloud & DevOps
AWSDockerKubernetes
AI
Generative AI
Practices
Problem SolvingTeamworkAjax
Portfolio

Featured projects

Some of my recent work and contributions.

01

Real Estate - Property listing

Problem

Client needed an efficient way to manage property listings for renting, buying, and selling with a robust admin panel.

Solution

Built a scalable backend using Node.js and MySQL. Implemented a comprehensive admin dashboard for seamless property management.

Impact

Streamlined property listing process and improved management efficiency by 40%.

NodeJS
MySQL
Javascript
02

Vibeflow

Problem

Startups needed a unified platform to collaborate and connect across multiple workspaces without friction.

Solution

Developed a high-performance backend using Node.js, Express, and MongoDB. Integrated AWS for scalability and Agora for real-time connection.

Impact

Successfully handled thousands of concurrent workspace connections with 99.9% uptime.

Nodejs
ExpressJS
MongoDB
03

Unify Payment Gateway

Problem

Developers struggled with fragmented payment integrations across different gateways.

Solution

Created a unified Node.js package that provides a single, clean API for multiple payment providers.

Impact

Reduced integration time by 60% for dozens of startups using the package.

NodeJS
NPM Package
04

ThumbAI

Problem

Content creators needed a way to generate engaging thumbnails quickly to boost engagement.

Solution

Built an AI-powered design platform using Next.js and Gemini API for instant thumbnail generation.

Impact

Enables users to create professional-grade thumbnails in under 30 seconds.

NodeJS
NextJS
Gemini API
05

Botennica

Problem

Businesses needed intelligent, context-aware customer support without manual training overhead.

Solution

Developed a SaaS platform with AI chatbots that learn from docs, videos, and web content using Gemini API and MongoDB.

Impact

Automated up to 80% of routine customer queries for early-stage SaaS clients.

NextJS
MongoDB
Gemini API
06

Ai-localize

Problem

Translating large volumes of documentation was expensive and slow due to high API costs.

Solution

Developed a Node.js package with intelligent Redis caching to reduce redundant AI translation calls.

Impact

Reduced translation API costs by up to 50% for high-traffic documentation platforms.

NodeJS
Redis
OpenAI
Background

Education

2018 - 2024

Bachelor in Technology (B.Tech) in Computer Science

Dev Bhoomi Group of Institute, Dehradun, India

2015 - 2017

12th

Dwarika Prasad Gayatri Inter College, India

The Difference

Why choose me

Backend Specialist

Focused expertise in server-side architecture, not a generic full-stack developer.

Production Experience

Years of experience building and maintaining real-world systems at scale.

Cost Optimization

I don't just build; I optimize for performance and reduce operational costs.

Scalable Architecture

I design systems that grow with your business using clean, maintainable code.

Get In Touch

Let's build something
scalable together

Ready to scale your backend or optimize your existing systems? I'm currently available for freelance projects (2-3 slots open).

sumitkumar993618@gmail.com India
Writing

Latest articles

Insights on backend scaling, performance, and architecture.

How AI-Localize Makes Document Translation Smarter and Cheaper

A deep dive into building an intelligent, cost-effective document translation system.

Read More

Botennica: The Affordable AI Chatbot Builder That Learns From Your Data

Learn how we built a cost-effective, intelligent chatbot platform for seamless customer support.

Read More