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I am a Java Full Stack Developer with over 8 years of experience designing, building, and supporting enterprise applications across financial services, retail, and large-scale business platforms. I specialize in Java 8/11/17, Spring Boot microservices, REST API design, and event-driven architectures using Kafka and JMS. I enjoy delivering reliable, high-performance backend services and intuitive Angular frontends, and I’m passionate about mentoring teammates and improving CI/CD pipelines for efficient, predictable releases. Beyond coding, I thrive in collaborative Agile environments where I can translate complex business needs into scalable technical solutions, perform root cause analysis during incidents, and help teams iterate rapidly while maintaining production stability.…I am a Java Full Stack Developer with over 8 years of experience designing, building, and supporting enterprise applications across financial services, retail, and large-scale business platforms. I specialize in Java 8/11/17, Spring Boot microservices, REST API design, and event-driven architectures using Kafka and JMS. I enjoy delivering reliable, high-performance backend services and intuitive Angular frontends, and I’m passionate about mentoring teammates and improving CI/CD pipelines for efficient, predictable releases. Beyond coding, I thrive in collaborative Agile environments where I can translate complex business needs into scalable technical solutions, perform root cause analysis during incidents, and help teams iterate rapidly while maintaining production stability.

Sheshank Kumaran

AI Engineer, Data Scientist, Full Stack Developer, +4

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I am a Java Full Stack Developer with over 8 years of experience designing, building, and supporting enterprise applications across financial services, retail, and large-scale business platforms. I specialize in Java 8/11/17, Spring Boot microservices, REST API design, and event-driven architectures using Kafka and JMS. I enjoy delivering reliable, high-performance backend services and intuitive Angular frontends, and I’m passionate about mentoring teammates and improving CI/CD pipelines for efficient, predictable releases. Beyond coding, I thrive in collaborative Agile environments where I can translate complex business needs into scalable technical solutions, perform root cause analysis during incidents, and help teams iterate rapidly while maintaining production stability.…I am a Java Full Stack Developer with over 8 years of experience designing, building, and supporting enterprise applications across financial services, retail, and large-scale business platforms. I specialize in Java 8/11/17, Spring Boot microservices, REST API design, and event-driven architectures using Kafka and JMS. I enjoy delivering reliable, high-performance backend services and intuitive Angular frontends, and I’m passionate about mentoring teammates and improving CI/CD pipelines for efficient, predictable releases. Beyond coding, I thrive in collaborative Agile environments where I can translate complex business needs into scalable technical solutions, perform root cause analysis during incidents, and help teams iterate rapidly while maintaining production stability.

Available to hire

I am a Java Full Stack Developer with over 8 years of experience designing, building, and supporting enterprise applications across financial services, retail, and large-scale business platforms. I specialize in Java 8/11/17, Spring Boot microservices, REST API design, and event-driven architectures using Kafka and JMS. I enjoy delivering reliable, high-performance backend services and intuitive Angular frontends, and I’m passionate about mentoring teammates and improving CI/CD pipelines for efficient, predictable releases.

Beyond coding, I thrive in collaborative Agile environments where I can translate complex business needs into scalable technical solutions, perform root cause analysis during incidents, and help teams iterate rapidly while maintaining production stability.

Skills

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Expert

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Work Experience

Java Full Stack Developer at PayPal

March 1, 2025 - Present

Designed and developed payment and account-serving microservices using Java 17, Spring Boot, and Spring Cloud to handle high-volume transaction workflows with graceful failure handling and full service recovery. Defined REST API contracts with OpenAPI/Swagger, implemented asynchronous Kafka data pipelines with retry topics and DLQs, and built Spring Batch reconciliation jobs with partitioned, restartable execution. Implemented circuit breakers and fallbacks for third-party API calls, configured RBAC with Spring Security, and delivered Angular dashboards for operations. Resolved slow Oracle queries through execution plan reviews and indexing improvements, and supported production on-call incidents with Splunk and CloudWatch. Maintained Jenkins CI/CD pipelines and Kubernetes deployment configurations to ensure consistent releases across environments.

AI Engineer at PayPal

March 1, 2025 - Present

Architected production-grade LLM applications using Python, FastAPI, JavaScript/TypeScript, LangChain, and LangGraph to enable secure conversational and workflow-based experiences that integrate account-servicing and payment APIs. Designed RAG pipelines over policy, transaction, and support data with document chunking, embeddings, and metadata filters to deliver grounded answers with source-aware responses. Built LangGraph-based multi-step agents with planning, memory, tool calling, and human handoff paths to empower operations teams investigating payment issues across tools. Implemented prompt templates, structured outputs, and robust retry logic for reliable backend parsing and UI consumption. Deployed AI services in Docker/Kubernetes on AWS with CI/CD and observability dashboards.

Java Full Stack Developer at Costco

March 1, 2024 - February 1, 2025

Developed and maintained internal legal and business workflow applications using Java 11 and Spring Boot, enabling contract approvals, document routing, and compliance tracking across multiple units. Standardized REST API contracts, error formats, and validation layers to resolve integration inconsistencies. Contributed to a microservices decomposition effort, created Angular UI screens for document submission and approvals, and integrated JMS and Kafka for asynchronous processing with transactional integrity.

AI Application Engineer at Costco

March 1, 2024 - February 1, 2025

AI-powered document intelligence workflow designer for legal and compliance operations using Python, LangChain, RAG, and vector search to help teams locate contracts, approvals, and policy documents. Built ingestion pipelines to extract text, normalize metadata, generate embeddings, and load content into vector databases and PostgreSQL-backed stores. Developed tool-using agents for clause lookup, approval-status checks, summarization, and routing recommendations. Exposed capabilities via FastAPI/Node.js REST endpoints for secure consumption by Angular/React interfaces. Added human-in-the-loop review for high-risk outputs and implemented asynchronous embedding refresh via Kafka/JMS.

Java Developer at 3i Infotech

January 1, 2019 - July 1, 2022

Developed and maintained backend modules for an internal financial services platform (J2EE, Spring MVC, Hibernate), including account management, transaction processing, and user administration. Built REST and SOAP services for external banking integrations, authored Oracle SQL queries and stored procedures with performance tuning, and contributed to server-side validation and JSP-based admin interfaces. Investigated production defects, authored design documents, and supported multi-release cycles.

Backend Engineer at 3i Infotech

January 1, 2019 - July 1, 2022

Developed Python and Java backend services for financial services workflows, including REST/SOAP integrations, data validation modules, and secure service layers for accounts, transactions, and user administration. Built enterprise search and document retrieval using vector/semantic search patterns and SQL metadata. Designed API integrations with banking systems and data providers with robust error handling, retries, and audit logging. Created data pipelines for classification, reconciliation, and reporting, extracting from Oracle, normalizing records, and preparing clean context data for analytics and AI-assisted search. Implemented prompt-style templates and rule-based NL summaries to aid operations analysts. Optimized Oracle SQL queries, stored procedures, and indexes for high-volume reporting.

Java Full Stack Developer at Persistent Systems

August 1, 2016 - December 1, 2018

Developed enterprise billing, subscription management, and account administration modules (Java 8, Spring Boot, Hibernate) and built REST endpoints with shared services. Created responsive Angular UIs, integrated with Kafka for decoupled notification flows, and configured Docker packaging with Jenkins/Maven pipelines. Established logging standards with Log4j and contributed to Agile ceremonies and release validation.

Software Engineer at Persistent Systems

August 1, 2016 - December 1, 2018

Built backend and full-stack modules for telecom billing, subscription management, and account administration using Java, Python, REST APIs, and Angular/JS frontends. Created API services and data processing utilities exposing clean customer, billing, and subscription data for dashboards and automation. Implemented Kafka-driven event processing to decouple billing notifications from subscription workflows. Automated data quality checks, release validation, and deployment pipelines with Docker, Jenkins/Maven, and environment-specific configuration. Participated in Agile ceremonies and code reviews to ensure reliable backend systems, cloud deployment, and production support.