Java Full Stack Engineer

Hi, I'm Vishnu Hari Sahal

I build full-stack applications with Java, Spring Boot, React, and SQL. My work spans REST APIs, database-backed services, and responsive interfaces, with hands-on experience in Kafka-based transaction processing and payment workflows. I focus on clean object-oriented design, reliable data flow, and software that's easy to maintain.

JavaSpring BootReactSQLREST APIsApache Kafka
See My Resume

Skills

Java and Spring Boot at the core, supported by React, SQL, and the tools to build complete web applications.

Languages

Java, object-oriented programming, and supporting languages

Java
Python
C++
JavaScript
SQL

Backend & Frameworks

Spring Boot services, REST APIs, and event-driven processing

Spring Boot
Apache Kafka
Node.js
Express.js
FastAPI

Frontend

Responsive interfaces with React and web fundamentals

React.js
HTML5
CSS3
Bootstrap

Databases

SQL data modeling, persistence, and NoSQL storage

MySQL
MongoDB
PostgreSQL

Cloud & Tools

Cloud, DevOps & developer tools

AWS
Git / GitHub
Docker
Linux/UNIX

Education

S.R.M. Institute of Science and Technology
B.Tech in Computer Science
Aug 2023 – PresentCGPA: 9.5/10

Location: Chennai, Tamil Nadu

  • Specializing in Computer Science & Engineering with focus on distributed systems, data structures, and backend architecture.
R.P.S. Public School
Senior Secondary (Class XII)
Apr 2021 – Mar 2023Score: 94%

Location: Haryana, India

  • Completed Senior Secondary Education with distinction in Physics, Chemistry, and Mathematics.

Experience

Hands-on work across web development, cloud infrastructure, and a Java / Spring Boot job simulation.

Wipro
Wipro

Cloud Computing Intern

WiproDec 2025 – Jan 2026

Cloud Computing Intern

Key Achievements
  • Implemented IAM best practices across cloud infrastructure, reducing potential security vulnerabilities by 15% based on weekly internal security audits
  • Developed and deployed Python automation scripts for routine infrastructure tasks, decreasing deployment errors by 12% and improving system reliability
  • Enhanced log monitoring coverage from 65% to 95% by building custom dashboards in cloud monitoring tools
Technologies & Tools
AWSIAMPythonCloud MonitoringDevOps
DoItForMe
DoItForMe

Lead Software Engineer – Web Development

DoItForMeFeb 2026 – Apr 2026

Lead Software Engineer – Web Development

Key Achievements
  • Built and maintained scalable backend and frontend features for a gig marketplace using Next.js 15, Supabase, and PostgreSQL
  • Integrated Cashfree Payment Gateway to power end-to-end payment orchestration — order creation, payment verification, and transaction tracking
  • Designed and implemented an escrow-based payment system for secure, fraud-safe holding of funds until transaction completion
  • Optimized payment flow performance and reduced latency by designing asynchronous, event-driven processing pipelines
Technologies & Tools
Next.js 15SupabasePostgreSQLCashfreeEscrowEvent-Driven
JPMorganChase & Co. (Forage)
JPMorganChase & Co. (Forage)

Software Engineering Job Simulation

JPMorganChase & Co. (Forage)Nov 2025

Software Engineering Job Simulation

Key Achievements
  • Engineered a Spring Boot microservice using Apache Kafka for real-time, high-throughput ingestion of financial transactions, sustaining 6,000 transactions/minute at 99.99% reliability
  • Implemented data validation, persistence, and downstream processing with Spring Data JPA on an H2 SQL database
  • Integrated external REST APIs and exposed analytical endpoints for processed transaction data, following SDLC best practices
Technologies & Tools
JavaSpring BootApache KafkaSpring Data JPAH2 SQLREST APIs

Projects

Java application development, full-stack web products, and data-driven services.

StockX – FinTech Stock Trading Platform
React.jsNode.jsExpress.jsMongoDB
  • Built a full-stack, real-time stock trading platform, reducing order placement latency by 150ms+ and trading errors by 10%
  • Architected trade execution, position updates, and portfolio calculations as distributed RESTful services, saving traders 5 hours weekly
  • Built interactive React dashboards visualizing holdings and performance, improving P&L data accuracy by 7%
VIEW PROJECT
Real-Time Credit Risk Prediction System
PythonScikit-LearnFastAPISHAP
  • Built a real-time loan default risk model, reducing false positives by 15% at a fixed decision threshold
  • Engineered an explainable risk-assessment microservice with FastAPI, cutting processing time by 30% for 800+ daily applications
  • Applied SHAP-based explainability with a visualization dashboard for transparent borrower risk insights
VIEW PROJECT
ePower Billing Suite
JavaSwingAWTJDBCMySQL
  • Developed a Java Swing electricity billing system (EBMS) handling 5,000+ monthly transactions, cutting billing processing time by 30%
  • Engineered a normalized 35-table MySQL database with JDBC integration, reducing security vulnerabilities found in penetration tests by 60%
  • Applied object-oriented design principles, reducing billing-related bug reports by 20% and improving system maintainability
VIEW PROJECT

Research and Publications

Co-author
Performance Evaluation of Small Language Models on Movie Review Dataset

IEEE Xplore — 2026 International Conference on AI Innovations and Industry (ICAIII)

IEEE Xplore Paper