Nithish Marneni

Experience

PayPal Aug 2024 – Present

Software Developer

Re-architected high-volume fraud mitigation pipelines as serverless REST APIs on AWS Lambda and API Gateway, cutting transaction-processing latency 35% at peak load
Engineered distributed Java/Spring Boot microservices on AWS ECS and EC2 that absorb peak financial traffic without degradation, instrumented with Prometheus
Shipped Amazon Bedrock–powered document validation into the exception-management flow, driving a 60% reduction in manual verification time
Hardened banking endpoints with OAuth2 and JWT authentication aligned to OWASP Top 10 guidelines
Built React/TypeScript components on AWS Amplify and S3, improving UI responsiveness 40% on customer-facing flows
Automated end-to-end CI/CD with Jenkins and Docker, containerizing core services to eliminate environment drift and accelerate delivery 50%
Adopted an AI-native development loop (Claude Code, Codex, Copilot) for scaffolding, test generation, and refactors while holding review and coverage standards

Target Jul 2021 – Jul 2023

Java Developer

Built Target's retail order management platform serving mobile, web, and in-store kiosks with Java/Spring Boot microservices, REST APIs, and Kafka event streaming, processing 1M+ transactions per day
Developed 20+ RESTful microservices (Spring Boot, Hibernate) powering core retail logic, including a routing engine connecting each customer to the nearest in-stock fulfillment center
Streamed millions of daily product-availability events via Kafka into real-time inventory webhooks across store, warehouse, and third-party vendor systems, monitored with Splunk and Grafana
Deployed ML-powered recommendation engines predicting purchase intent, plus React associate dashboards that cut manual inventory lookup time and lifted sales
Optimized PostgreSQL and DynamoDB (with DAX caching) for catalog metadata and session storage, accelerating read access on high-traffic paths
Built an Angular/TypeScript analytics dashboard tracing the full order lifecycle, and multi-language UI support (React Hooks, Context API) for global store regions
Delivered zero-downtime deployments through Jenkins, Docker, and AWS Lambda/API Gateway pipelines; wrote JUnit/Mockito and TestNG suites enforcing PCI-DSS and CCPA compliance

Selected Work

Featured Project

Microservices Banking Platform

End-to-end banking system with a service registry, API gateway, and independent user, account, fund-transfer, and transaction services — JWT-secured, containerized, and designed for horizontal scale. Java, Spring Boot, Spring Cloud, Spring Security.

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Fraud Detection System

Real-time fraud detection with ML models for transaction analysis and risk scoring.

#Java #SpringBoot #Analytics

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Financial API Service

RESTful API for financial data with authentication and rate limiting.

#Java #REST #SpringBoot

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Real-Time Chat System

Multi-threaded chat with message queuing and real-time communication patterns.

#Java #Networking #Architecture

Skills

Languages

Java (8/11/17/21) Python JavaScript TypeScript SQL

Backend & Architecture

Spring Boot Spring Security Spring Cloud Hibernate/JPA Node.js Express REST APIs Microservices Event-Driven Architecture Apache Kafka RabbitMQ OAuth2/JWT OWASP Top 10

Frontend

React Next.js Redux React Hooks/Context API Angular Tailwind CSS Bootstrap HTML5 CSS3

Cloud & Data

AWS Lambda API Gateway ECS / EKS / EC2 S3 Amplify DynamoDB/DAX Bedrock Azure PostgreSQL MySQL SQL Server MongoDB Redis

AI-Native Engineering

Claude Code OpenAI Codex GitHub Copilot Cursor Anthropic & OpenAI APIs Amazon Bedrock LangChain RAG Vector Search Prompt Engineering MCP Agentic Workflows Hugging Face PyTorch TensorFlow

DevOps & Quality

Docker Kubernetes Terraform Jenkins GitHub Actions Git Maven JUnit Mockito TestNG Selenium Postman Grafana Prometheus Splunk Jira Agile/Scrum PCI-DSS & CCPA