Hire the Best Java Collections Framework (JCF) Professionals
Ukrainka, Ukraine
๐ Hello! Senior Java Developer, Team Lead & Architect with 10+ years of hands-on experience with 10+ years of hands-on experience building scalable, high-load web and mobile applications. I mainly work with Java backend, JavaScript, TypeScript, Oracle, Postgres databases. My core backend work is centered on Spring Boot, focusing on API development and production-grade RESTful services backed by PostgreSQL. My focus is on backend software architecture, ensuring scalability, clean boundaries, and long-term maintainability. โ๏ธ Ready-to-Use Integrations I can accelerate your product using proven, production-ready integrations: ๐ AI & LLMs: ChatGPT, LLaMA, Mistral (text, images, vision, automation) ๐ Payments: Stripe (card payments & transfers) ๐ Voice & Media: ElevenLabs (speech & voice AI) ๐ Communication: Zoom (voice & video integrations) My Specialization: โ Backend & Architecture: Java (10+ years): modern Java (Lambdas, Streams, Date/Time API), Spring (9+ years): Spring Boot, Spring Data, Spring Cloud for microservices and distributed systems, and Java EE: REST APIs, SOAP, JPA, third-party integrations โ Security & Frameworks: Keycloak with OAuth2 and JWT-based authentication, JHipster, Swagger, Liquibase, Axon, Vaadin, ORM: Hibernate, Blaze-Persistence โ Databases & Messaging: SQL (10+ years): PostgreSQL, MySQL, MariaDB, Oracle, NoSQL: MongoDB, Redis, Hazelcast, Messaging: Kafka, ActiveMQ, RabbitMQ, Zookeeper, Firebase Messaging โ DevOps & Observability: CI/CD: Jenkins, Docker, Kubernetes, ELK Stack (Logstash, Elasticsearch, Kibana) โ Quality & Delivery: Testing: JUnit, Mockito, Spring Test, Unit & Integration testing, Full SDLC, code reviews, refactoring, clean architecture ๐ก Letโs discuss how I can help you build a reliable, scalable solution!
- Java
- Spring Boot
- RESTful API
- Apache Kafka
- PostgreSQL
- Spring Framework
- Spring Cloud
- Docker
- Kubernetes
- OAuth
- Hibernate
- CI/CD
- API Development
- Software Architecture
Hyderabad, Pakistan
Full Stack Java Engineer with 5+ years of experience building scalable, production-grade systems for logistics, food delivery, and enterprise platforms. I specialize in Spring Boot microservices architecture and AI-powered backend systems โ designing end-to-end solutions that handle high traffic, complex workflows, and real-time data processing. My background in logistics technology means I understand not just the code, but the business operations behind it. What I bring to your project: - AI integration using OpenAI, Gemini, and LangChain4j for intelligent automation and chatbot backends - Microservices architecture with Spring Boot and Spring Cloud - Event-driven systems using Apache Kafka and RabbitMQ - Full stack development with React.js and Vue.js frontends - REST API design, development, and third-party integrations - AWS infrastructure โ EC2, RDS, S3, deployment pipelines - Database design and optimization across MySQL, PostgreSQL, and Oracle - JWT-based authentication and Spring Security - Legacy system migrations and monolith-to-microservices transitions - Docker, CI/CD pipelines, and production deployment I have built and maintained systems processing hundreds of thousands of records daily โ including a 2.5-year long-term engagement delivering a full-stack logistics and food delivery platform on AWS, earning a 5.0 rating across every review. I do not disappear after handing over code. I ask the right questions before starting, communicate clearly throughout, and flag issues before they become problems. Clients who work with me once tend to come back. 100% Job Success Score across every contract on Upwork. If you need a reliable full-stack engineer who builds intelligent, scalable systems โ let's talk.
- Java
- Spring Boot
- REST API
- Microservice
- Apache Kafka
- Amazon Web Services
- Spring Security
- API Integration
- Spring Cloud
- Hibernate
- MySQL
- PostgreSQL
- MongoDB
- Spring MVC
- Next.js
- Vue.js
- RabbitMQ
- React
- Docker
- Artificial Intelligence
Daska Kalan, Pakistan
A ๐๐จ๐ฉ ๐๐๐ญ๐๐ ๐๐ฎ๐ฅ๐ฅ ๐ฌ๐ญ๐๐๐ค ๐๐๐ฏ๐๐ฅ๐จ๐ฉ๐๐ซ ๐ฐ๐ข๐ญ๐ก ๐ ๐๐๐% ๐๐จ๐ ๐๐ฎ๐๐๐๐ฌ๐ฌ ๐๐๐จ๐ซ๐ building Java Spring Boot backends, modern web apps, n8n automations, and WordPress solutions that are robust, scalable, and delivered on time. I work at the intersection of enterprise backend engineering, full stack product development, AI-powered workflow automation, and WordPress helping startups launch MVPs quickly and helping businesses eliminate the manual work that slows their teams down. ๐ What I'm Best At: ๐น๐๐๐ฏ๐ & ๐ ๐ฎ๐ฅ๐ฅ ๐๐ญ๐๐๐ค ๐๐๐ฏ๐๐ฅ๐จ๐ฉ๐ฆ๐๐ง๐ญ (๐๐จ๐ซ๐ ๐๐ฑ๐ฉ๐๐ซ๐ญ๐ข๐ฌ๐): โ ๐๐๐ฏ๐ ๐๐๐จ๐ฌ๐ฒ๐ฌ๐ญ๐๐ฆ: Spring Boot, Spring MVC, Spring Security, Spring Data JPA, Spring Cloud, Hibernate, Kotlin ๐ฅ๏ธ ๐ ๐ซ๐จ๐ง๐ญ๐๐ง๐: Next.js, React, TypeScript, Angular, Tailwind CSS ๐ป ๐๐๐๐ค๐๐ง๐: Node.js (Express, NestJS), Python (FastAPI, Django) ๐พ ๐๐๐ญ๐๐๐๐ฌ๐๐ฌ: PostgreSQL, MySQL, MongoDB, Redis โ๏ธ๐๐๐ฏ๐๐ฉ๐ฌ & ๐๐ฅ๐จ๐ฎ๐: AWS (EC2, S3, RDS, CloudFront, Lambda), Docker, Kubernetes, GitHub Actions, Jenkins ๐น n8n Automation & AI Workflows: ๐ง Workflow Automation: n8n, Zapier, Make connecting your tools and cutting out repetitive manual work entirely ๐ค AI Integration: OpenAI, Claude, Gemini embedded intelligently into your products and business processes ๐ฃ CRM & Lead Automation: email pipelines, WhatsApp, Slack, webhook-driven workflows, outreach systems ๐ฆ Custom Automations: data sync, onboarding flows, report generation, notification systems, document processing ๐น WordPress & WooCommerce: โก Custom themes and plugins built from scratch no bloated templates ๐ WooCommerce: payments, subscriptions, multi-vendor marketplaces ๐ Performance optimization, security hardening, malware cleanup, and full site migrations ๐งฉ Page builders: Elementor Pro, Divi, Bricks, WPBakery, Gutenberg ๐น Why Work With Me: โบ Top Rated with 100% Job Success consistent results across every engagement โบ I take full ownership of outcomes not just tasks and keep you informed at every step โบ Clean, well-documented code your team can maintain without needing me forever โบ AI-powered development workflow: I ship faster without sacrificing quality or cutting corners โบ Clear, proactive communication you'll never be left guessing about progress โญ What clients say: "Hamdan demonstrated strong expertise in Java Spring Boot and Next.js clean, efficient code that met all requirements." Marketplace Platform (681 hrs ยท $2,241) "Completed the AWS deployment exactly as promised. Highly recommend for CI/CD and AWS configuration." Spring Boot + AWS DevOps "Very understanding and always available. He makes sure everything is clear before moving forward." n8n CRM Automation "Delivered exactly what was needed with minimal instructions. Sincere, hard-working โ I would highly recommend." NestJS / Angular + DevOps ๐ค Let's Talk โ you might be a great fit if you need: - A Java Spring Boot API or full stack web application built properly from day one - An n8n automation workflow that saves your team hours every single week - A marketplace, SaaS MVP, or internal tool launched in weeks not months - A fast, secure, and conversion-ready WordPress or WooCommerce site - A reliable developer who communicates clearly, delivers consistently, and cares about your success Click "Invite to Job" or send me a message I'd love to hear about your project. ๐
- Java
- Spring Boot
- API
- RESTful API
- Docker
- React
- Amazon Web Services
- API Integration
- MySQL
- Spring Security
- Spring MVC
- Spring Framework
- Spring Batch
- Microservice
- J2EE
Lahore, Pakistan
๐ Hello, I'm Kashaf Shanawar! Iโm a passionate Java & Angular Developer with expertise in building dynamic, scalable, and high-performing web applications. With over 2 years of hands-on experience, I specialize in designing and developing full-stack applications with robust Java Spring Boot backends and interactive Angular frontends. ๐ก What I Offer: โ Full-Stack Development โ Expertise in Java Spring Boot and Angular, ensuring seamless integration between backend and frontend. โ API Development & Integration โ Proficient in creating and securing RESTful APIs. โ Database Management โ Experienced with MySQL, PostgreSQL, and MongoDB for efficient data storage and retrieval. โ Authentication & Security โ Implementing Spring Security & JWT for secure applications. โ Microservices Architecture โ Developing scalable and distributed systems with Spring Boot microservices. โ Trading Systems Development โ Worked on real-time trading platforms integrated with stock exchanges, handling market data, FIX protocols, and order management systems (OMS). ๐ Tech Stack: Backend: ๐ฅ Java (JDK 8, 11, 17, 21) | Spring Boot | Spring Security | Hibernate (JPA) | REST APIs | Microservices | Kafka Frontend: โก Angular | TypeScript | JavaScript | HTML5 | CSS3 Database: ๐ MySQL | PostgreSQL | MongoDB Tools & Platforms: ๐ Git | Jira | Postman | Docker ๐ผ Work Experience: ๐น Java Angular Developer | Softech Systems Limited (2023 โ Present) Building scalable Java Spring Boot applications with REST APIs & microservices. Developing real-time trading platforms with Pakistan Stock Exchange (PSX) & Ghana Stock Exchange integration. Enhancing Order Management System (OMS) and implementing STOP/LOSS trading functionalities. Revamping the trading terminal using Angular for a smoother user experience. ๐น Full Stack Java Angular Intern | Zin Technologies (2023) Developed full-stack applications with Java Spring Boot, Angular, and MySQL. Worked in Agile environments with Git and Jira for project management. ๐ฅ Why Hire Me? โ 100% Client Satisfaction โ I prioritize delivering high-quality, well-structured, and efficient code. โ Deadline-Oriented โ I ensure timely delivery while maintaining excellent code quality. โ Strong Problem-Solving Skills โ I love challenges and always find innovative solutions. โ Effective Communication โ Clear, proactive, and transparent communication for seamless project execution. โ Continuous Learner โ Always eager to explore the latest technologies and best practices. ๐ฉ Letโs Work Together! Looking for a reliable, detail-oriented, and skilled full-stack developer to take your project to the next level? Let's discuss how I can help! ๐จ Message me now, and let's build something amazing together! ๐
- Java
- Web Application
- CSS
- HTML
- Spring Boot
- Microservice
- Angular
- MySQL
- Spring Security
- Spring Framework
- Kafa
- Websockets
- Hibernate
- JavaScript
- TypeScript
Cairo, Egypt
Senior Java Backend Developer with 10+ years building production systems using Spring Boot, REST APIs, and enterprise databases. CORE EXPERTISE: - Spring Boot, Spring MVC, Spring Data JPA, Spring Security - RESTful API design and development - Database design: MySQL, Oracle - Enterprise system integration - Production support and troubleshooting WHAT I DELIVER: - Spring Boot Enterprise applications and RESTful APIs - Database design and optimization (PostgreSQL, MySQL, Oracle) - System integrations and workflow engines - Application support and troubleshooting RECENT HIGHLIGHTS: - Built configurable workflow engine processing thousands of events - Designed multi-system integrations with comprehensive error handling - Kotlin + Spring Boot experience TECHNICAL SKILLS: Java, Spring Boot, Spring Framework, Kotlin, REST APIs, PostgreSQL, MySQL, AWS, Docker, Git, Agile/Scrum MICROSERVICES KNOWLEDGE: - Strong understanding of microservices architecture patterns through coursework and demo projects. Seeking opportunities to apply this knowledge in production environments and build distributed systems expertise under experienced architects. I have a 5.0 Upwork rating and clients describe me as "professional, responsive, and genuinely committed to delivering high-quality work." Available for long-term contracts (30+ hours/week).
- Java
- Spring Boot
- Spring Framework
- RESTful Architecture
- REST API
- Microservice
- Amazon Web Services
- Kotlin
- MySQL
- PostgreSQL
- Git
- Apache Kafka
- Scrum
- Apache Maven
- Docker
Jaipur, India
Java Spring Developer with over 15+ years of experience building scalable, high-performance solutions across diverse industries. Technical Expertise โ Spring Ecosystem: Spring Boot, Spring Batch, Spring Cloud, Spring Security, Spring AOP, Spring MVC, JSP, Thymeleaf. โ AI : Claude , Codex , RAG ,Integration with OpenAI โ Microservices & APIs: Microservices architecture, RESTful APIs. โ Messaging & Event-Driven Systems: Apache Kafka, WebSocket, STOMP, Socket IO โ Cloud Integration: AWS (ECS Fargate, S3, EC2, ALB, RDS). โ Database Design: SQL (MySQL, Oracle, Yugabyte, PostgreSQL, MS SQL Server) โ DevOps & Containers: CI/CD pipelines, Jenkins, Docker, Podman, Kubernetes โ Search & Caching: Elasticsearch, Redis, Terracotta Caching โ System Integration & Legacy Modernization: Seamlessly integrate modern applications with legacy systems โ Frameworks & Tools: JHipster, Keycloak, Flowable, JBPM, Flyway, MapStruct, JavaFX, Java Swing โ CMS Solutions: Documentum, Alfresco โ XML & Web Services: SOAP, RESTful services โ Reporting Tools: Crystal Reports, JasperReports, BIRT โ Testing Framework/Tools: Junit5,Selenium,JMeter
- Java
- Spring Boot
- RESTful API
- SQL
- Spring Batch
- Spring Security
- Docker
- Documentum
- Elasticsearch
- Apache Kafka
- Amazon ECS for Kubernetes
- Microservice
- Hibernate
- Websockets
- Swing
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