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SUNIL SAINISoftware Engineer
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Software Engineer (Backend)

Sunil SainiBuilding systems that scale with confidence.

Backend developer focused on Spring Boot, WebSockets, Redis, and Kafka — building real-time and scalable systems.

Haryana, IndiaOpen to Software Developer roles
View ProjectsContact Me
GitHubLinkedInEmail
5+
Backend Projects
Kafka + WebSocket
Real-time Systems
JWT + OAuth2
Security Systems
About

Engineering with product clarity and platform depth

B.Tech Computer Science student with hands-on experience in building real-time and distributed backend systems. Skilled in Spring Boot, Kafka, Redis, and WebSockets, with a strong focus on system design, scalability, and clean architecture.

I am a backend-focused Software Engineer currently pursuing B.Tech in Computer Science. I enjoy building scalable systems and solving real-world backend problems.

My experience includes implementing secure authentication systems using Spring Security with JWT and OAuth2, and designing APIs with proper architecture and performance considerations.

Experience

Fresher

Location

Haryana, India

  • Led architecture and delivery for products serving millions of active users.
  • Strong track record in performance optimization, reliability, and developer experience.
  • Comfortable owning systems end-to-end across frontend, backend, and cloud infrastructure.
Skills

Depth across product engineering and scalable architecture

Hands-on across full-stack delivery, with strong emphasis on maintainability, reliability, and measurable performance gains.

Backend & Core

JJava
90%
SBSpring Boot
92%
SSSpring Security
88%
JPAHibernate / JPA
85%

Systems & Messaging

KKafka
80%
RRedis
85%
WSWebSocket
90%
SDSystem Design
82%

Tools & Others

SQLMySQL
88%
MMongoDB
75%
DDocker
70%
GGit / GitHub
85%
Experience

Six-plus years of impact across product, platform, and scale

Progressive ownership from product delivery to architecture leadership across high-availability systems.

Java Developer Intern

Aptron Solutions

June 2024 - July 2024

India

Worked on Java-based applications focusing on backend logic and system design.

  • Developed a banking system using Java Servlet and MVC architecture.
  • Implemented transaction handling with ACID properties using logging mechanisms.
  • Worked on backend logic, request handling, and data flow management.

Java Developer Intern (Virtual)

Deloitte (Forage)

2024

Remote

Completed a virtual internship focused on backend systems using Spring Boot.

  • Worked on Kafka integration for event-driven architecture.
  • Implemented H2 database usage with Spring Boot.
  • Gained understanding of microservices communication patterns.
Projects

Selected work with production-scale outcomes

Representative projects focused on reliability, throughput, user experience, and engineering velocity.

Real-time Chat Application (E2EE Ready)

A real-time chat system using WebSocket and Redis with support for message persistence, caching, and cursor-based pagination.

Designed scalable messaging architecture with real-time communication and optimized message retrieval.

Spring BootWebSocketRedisMySQL
CodeLive Preview

Kafka Notification Service

Event-driven notification system supporting Email, Text, and App notifications using Kafka.

Implemented retry mechanism with dead-letter queue (DLT) for fault tolerance.

Spring BootKafkaMicroservices
CodeLive Preview

Spring Security System

Comprehensive authentication system with JWT, OAuth2 (Google/GitHub), and Basic Authentication.

Handled secure authentication and authorization with multiple strategies.

Spring BootSpring SecurityJWTOAuth2
CodeLive Preview

AI Email Generator Extension

Chrome extension integrated with Gemini API to generate email replies automatically.

Automated email drafting using AI, improving productivity.

Spring BootGemini APIJavaScript
CodeLive Preview
Tech Stack

Tools I use to build fast, resilient products

A practical stack tuned for product velocity, operational reliability, and long-term maintainability.

Languages

JavaPythonCSQL

Frameworks

Spring BootSpring SecurityHibernateReact (Basic)

Data & Messaging

MySQLMongoDBRedisKafka

Tools

DockerGitGitHubPostman
Achievements

Certifications and recognition

Signals of technical depth, delivery impact, and engineering leadership over time.

Java Developer Internship

Aptron Solutions

2024

Completed hands-on training in Java backend development.

Deloitte Virtual Internship

Forage

2024

Worked on Spring Boot and Kafka-based backend tasks.

C Programming Certification

Calicut University

2023

Strong foundation in programming using C.

Cyber Security Certification

Dr. B.R. Ambedkar University

2023

Basic knowledge of cyber security concepts.

Contact

Let us build the next high-leverage product

Open to impactful product engineering challenges, platform modernization programs, and senior architecture roles.

Feel free to reach out for opportunities, collaborations, or backend engineering roles.

mrsunilsaini3600@gmail.com

Send me a message and I will reply soon.

Social Links

GitHub@mrsunil3600LinkedInSunil SainiEmailmrsunilsaini3600@gmail.com