✅ 8+ Years of Java Development Experience
⚡ Full-Cycle Backend Development & Architecture
⚡ AI-Powered Development for Faster Delivery & Better Code Quality
👀 Click Invite or Hire for Scalable Java Backend Solutions
Looking for a Java Developer who can build scalable backend systems, SaaS platforms, enterprise applications, and cloud-native solutions designed for long-term growth?
For 8+ years, I have helped startups, SaaS companies, fintech businesses, AdTech platforms, and enterprise organizations build secure, scalable, and high-performance software using Java, Spring Boot, PostgreSQL, MySQL, Kafka, GraphQL, AWS, Docker, Kubernetes, and modern cloud technologies.
From backend architecture and microservices development to legacy application modernization, API integrations, troubleshooting, cloud deployments, and AI-assisted engineering, I deliver production-ready solutions built to scale.
👉 WHAT YOU GET:
✔️ Java Backend Development & Software Architecture
✔️ Spring Boot Applications & Microservices
✔️ REST APIs, GraphQL APIs & Integrations
✔️ Cloud-Native Applications using AWS
✔️ AI-Assisted Development & Automation
✔️ Legacy System Modernization
✔️ Long-Term Support, Maintenance & Optimization
🏆 KEY ACHIEVEMENTS:
✔️ 8+ years building Java, Spring Boot, and enterprise backend applications
✔️ Built scalable SaaS platforms, fintech applications, AdTech systems, and enterprise software
✔️ Maintained and enhanced 15+ production microservices
✔️ Contributed to Adstrome, TrustArc, Acquia DAM, and Digi-Docket
✔️ Designed secure APIs, event-driven systems, and scalable architectures
✔️ Improved application performance through optimization and modernization
⚙️ CORE EXPERTISE:
✔️ Java, Core Java, Java EE, Spring Boot, Spring MVC, Spring Security
✔️ Hibernate, JPA, JDBC, MyBatis, ORM Frameworks, REST APIs, GraphQL APIs
✔️ Microservices Architecture, Apache Kafka, Event-Driven Systems
✔️ PostgreSQL, MySQL, Snowflake, Query Optimization
✔️ AWS, Docker, Kubernetes, Jenkins, Maven, Gradle, Git, GitHub, Bitbucket, Version Control Systems
✔️ Authentication, Authorization, RBAC, Multi-Tenant SaaS
✔️ ZK Framework & Enterprise Web Application Development
🛠 DEVELOPMENT & MAINTENANCE:
✔️ Web Application Development & Enterprise Software Development
✔️ Spring MVC & ZK Framework Application Development
✔️ Legacy Application Maintenance, Modernization & Application Upgrades
✔️ Feature Development & Application Enhancements
✔️ Bug Fixing, Root Cause Analysis & Production Support
✔️ Performance Bottleneck Analysis & Optimization
✔️ Memory Leak Detection & Resolution
✔️ Security Vulnerability & CVE Remediation
✔️ Third-Party API Integration & Business Workflow Automation
✔️ Performance Optimization & Scalability Improvements
☁️ CLOUD & DEVOPS:
✔️ AWS Cloud Services, Docker Containerization & Containerized Application Deployment
✔️ Kubernetes Container Orchestration for Scalable Cloud Infrastructure
✔️ Linux-Based Server Systems, Linux Server Administration & Linux Server Troubleshooting
✔️ Apache Tomcat Installation, Deployment, Monitoring & Performance Tuning
✔️ CI/CD Pipelines, Jenkins Automation, Git, GitHub, Bitbucket & Version Control Systems
✔️ Web Application Troubleshooting, Production Environment Support & Incident Resolution
🧪 TESTING & QUALITY:
✔️ JUnit, Mockito, Unit Testing & Integration Testing
✔️ Test-Driven Development & Automated Testing
✔️ API Testing, Debugging & Log Analysis
✔️ Root Cause Investigation & Production Stability
✔️ Code Quality Improvements & Maintainable Software Development
✔️ Regression Testing & Application Reliability Improvements
🤖 AI-ENHANCED ENGINEERING:
✔️ AI-Assisted Development & AI-Powered Coding Workflows
✔️ OpenAI API Integration, LLM Workflows & AI Automation
✔️ AI-Assisted Testing, Refactoring & Documentation
✔️ Faster Delivery Through AI-Enhanced Engineering
🏢 INDUSTRY EXPERIENCE:
✔️ SaaS Platforms & Enterprise Applications
✔️ AdTech & Programmatic Advertising
✔️ Fintech & Loan Processing
✔️ Privacy & Compliance Systems
✔️ Digital Asset Management
✔️ Multi-Tenant & White-Label Solutions
🚀 WHY CLIENTS CHOOSE ME:
✔️ 8+ Years of Java Development Experience
✔️ Enterprise SaaS & Microservices Expertise
✔️ Strong Spring Boot & Cloud-Native Skills
✔️ Scalable, Secure & Maintainable Solutions
Whether you need to build a backend platform from scratch, scale an existing SaaS application, maintain a legacy system, resolve performance bottlenecks, remediate security vulnerabilities, implement microservices, modernize enterprise software, deploy applications on Tomcat or Linux-based server systems, integrate AI capabilities, or optimize application performance, I can help.
Looking for a Java Developer, Senior Java Developer, Java Backend Developer, Spring Boot Developer, Java Architect, Backend Engineer, Enterprise Software Developer, API Developer, GraphQL Developer, AWS Developer, Cloud Engineer, Kafka Developer, Software Architect, Backend Architect, or Java Consultant?
Spring Boot
Spring Security
Microservice
Java
Core Java
Hibernate
Spring Framework
Spring MVC
Spring Batch
RESTful API
Jakarta EE
MySQL
Apache Kafka
JUnit
Java Servlet API
JSTL
Thymeleaf
Amazon Web Services
Back-End Development
Web Development
Saif R.
Gujrat, Pakistan
$25/hr
5.0
19 jobs
Are you looking to build a high-performance software application from scratch? Or do you need a seasoned technical leader who can effortlessly bridge the gap between complex backend architecture and a highly responsive, visual frontend?
With over 13 years of enterprise-level experience, I specialize in taking web systems from a blank canvas all the way to a polished, production-ready end product.
Technologies & Frameworks Working Experience (Backend + Front-End)
Java
Spring Boot
Micro-Services
REST API
MySQL
DynamoDB
MongoDB
Angular 4
Tailwind CSS
Svelte 5 + SvelteKit
D3.js
Fabric.js
Dynamic SVG Rendering
AWS Cloud Infrastructure (EC2 , ECS , Cloudwatch , Cloudformation , S3 , Lambda , Amplify , Route53 , VPC , Load Balancing , ASGs)
Git (Code Managment)
Development of Data-Rich Interfaces
Whether you are launching a new platform from the ground up or modernizing an existing legacy ecosystem, I bring the technical depth, execution speed, and architectural oversight needed to ensure success.
JavaScript
Java
Web Development
D3.js
Svelte
Spring Boot
Data Visualization
Interactive Data Visualization
Data Analytics & Visualization Software
Technical Writing
Blog Writing
Product Development
Tailwind CSS
MySQL
MongoDB
AWS CloudFormation
AWS Amplify
AWS Lambda
Amazon EC2
Amazon ECS
CAO DANG T.
Hanoi, Vietnam
$35/hr
4.7
70 jobs
I have been working with Java language for around ten years on many aspects of Java from core java to J2EE, Java web, and also with some famous java framework such as Spring, Hibernate, Kafka, Elastic Search, Lucene, and many others. My experience technology stack:
- Java
- Spring Framework (Core, MVC, Boot, Security, Microservices, Cloud, OAuth)
- Dropwizard
- Hibernate
- Restful and SOAP web service
- Postgres, MySQL, MongoDB
- JavaScript, TypeScript, Angular, ReactJS, NodeJS
- DevOps
- Jenkins, Docker, Kubernetes, GitOps
- Cloud
- AWS, GCP
Spring Framework
SQL
GraphQL
Kubernetes
API Integration
Docker
Microservice
Hibernate
Software Architecture & Design
Amazon Web Services
Apache Kafka
NoSQL Database
CI/CD
Wiwit Aditya S.
Pemalang, Indonesia
$30/hr
5.0
27 jobs
Hi there
You can call me Wiwit, I'm from Indonesia
I started my career as a web developer in 2010 and started working on Upwork from 2015.
I have good experience in developing web based enterprise solutions using Java technologies like J2EE, JSF, REST, SOAP, Hibernate and Springboot
Proficient with angularjs, reactjs and good experiences with any popular js family.
I also very good for debugging and tracking.
I'm looking for customers for long-term cooperation. I would like to offer you my skills and experience to solve your issues.
Spring Framework
TypeScript
Java
JavaScript
Node.js
Bhavin P.
Ahmedabad, India
$25/hr
5.0
38 jobs
🎯 Liferay DXP 7.4 Certified Professional Back-End Developer
⌛ 10 Years on Liferay Platform
🏆 100% Job Completion | Top Rated on Upwork | 7500+ Hours on Upwork
I have 10 years of expertise in Software Development, Solution Architecture, and Product Design, with a strong focus on Liferay and Spring technology.
💼 𝐓𝐞𝐜𝐡𝐧𝐢𝐜𝐚𝐥 𝐒𝐤𝐢𝐥𝐥 :
𝐂𝐨𝐫𝐞 : Java, J2EE, Liferay(6.X/7.X), Spring Boot, JSF, PrimeFaces,Icefaces, Richfaces, FHIR, ABDM, SNOMED-CT,REST, SOAP web services
𝐅𝐫𝐨𝐧𝐭-𝐄𝐧𝐝 : AngularJS, ReactJS, HTML4/5, XHTML, XML, CSS3, jQuery, JavaScript, AJAX
𝐒𝐞𝐫𝐯𝐞𝐫𝐬 : Tomcat, JBoss/Wildfly and Jetty, GlassFish
𝐒𝐞𝐜𝐮𝐫𝐢𝐭𝐲 : Spring Security, OAuth2, JWT
𝐃𝐚𝐭𝐚𝐛𝐚𝐬𝐞 : SQL, MySQL, PostgreSQL, MongoDB and Oracle
𝐈𝐧𝐭𝐞𝐠𝐫𝐚𝐭𝐢𝐨𝐧𝐬 : Gmail, Google Meet, Google Calendar, Zoom, RazorPay, Stripe, SMTP, Twilio, DocuSign, Google Maps API, PayPal
𝐇𝐞𝐚𝐥𝐭𝐡𝐂𝐚𝐫𝐞 𝐒𝐭𝐚𝐧𝐝𝐚𝐫𝐝 : FHIR | EHR | EMR | SNOMED | HL7 | OpenEHR | OpenEMR | ABDM
𝐒𝐞𝐚𝐫𝐜𝐡-𝐄𝐧𝐠𝐢𝐧𝐞𝐬 : Apache Solr, Elastic Search
𝐂𝐥𝐨𝐮𝐝 𝐚𝐧𝐝 𝐃𝐞𝐯𝐨𝐩𝐬 : AWS, Google Cloud, Azure, Jenkins, CICD, Docker, Kubernetes
𝐓𝐞𝐬𝐭𝐢𝐧𝐠 : JTest, JUnit, Mockito and Powermock
𝐂𝐨𝐝𝐞 𝐐𝐮𝐚𝐥𝐢𝐭𝐲 𝐓𝐨𝐨𝐥𝐬 : Crucible and Sonarqube
𝐁𝐮𝐢𝐥𝐝 𝐭𝐨𝐨𝐥𝐬 : Maven, Gradle, Ant, npm, grunt and webpack
𝐕𝐂𝐒 : SVN, GIT, GITLAB, Bitbucket
𝐎𝐒 : Linux, Windows and Mac OS
𝐁𝐮𝐠/𝐈𝐬𝐬𝐮𝐞 𝐭𝐫𝐚𝐜𝐤𝐞𝐫𝐬 : Jira, asana, Trello
🔐𝐋𝐢𝐟𝐞𝐫𝐚𝐲 𝐄𝐱𝐩𝐞𝐫𝐭𝐢𝐬𝐞 :
➜ Expert in almost all OOTB features [ Sites, Pages, Webcontents, Fragments, Layouts, Asset Publishers, Categories, Tags, Search, Workflows, User Management, Roles, Permission, User Groups ]
➜ Implemented Custom Portlets [ using MVC, React, Spring, JSF, service builder and standards like OSGI, JSR 168 and 268 ]
➜ Implemented REST API using Liferay Rest builder
➜ Implemented themes [ using Freemarker, velocity ],
➜ Customized Liferay [ using Service wrapper, Portlet filter, Lifecycle events, Model listeners,
Search contributors, JSP, Core Classes ]
➜ Implemented Web Fragment [ Freemarker, HTML, CSS, Javascript ]
➜ Implemented SSO Integration supports SAML, Keycloak, LDAP, OpenId, OAuth, and more
➜ Implemented SMS and WhatsApp Integration using Twilio
➜ Implemented Third-Party integration using REST API or client SDK
➜ I have recently upgraded Liferay 7.0 to Liferay 7.4 including data and code migration both.
Looking forward to working with you to develop and deliver a fantastic product and Solutions as per your Business Requirements.
Jakarta Server Faces
Hibernate
Java
Spring Security
PrimeFaces
Spring Framework
Spring Boot
MySQL
React
Bootstrap
CSS
HTML
Web Development
Liferay
Ashrik A.
Colombo, Sri Lanka
$25/hr
5.0
26 jobs
I'm a rare mix: a full-stack engineer who also builds and scales anti-detect, multi-account, and automation systems, and actually worked inside the tooling as a developer at Multilogin.
With 5+ years of hands-on experience, I specialize in Java/Spring Boot, Angular, and modern full-stack development, delivering clean architecture, optimized performance, and production-ready systems.
✔What I bring to your project:
• Robust REST APIs & Microservices (Spring Boot, JPA, Security)
• Scalable Frontend Applications (Angular, Vue, MERN/MEAN)
• Secure Authentication Systems (JWT, OAuth 2.0, SSO, Azure AD)
• High-performance Database Design & Optimization (MySql, MSSql, MongoDB)
• Seamless API Integrations & Messaging (RabbitMQ, Azure service bus)
✔AI & LLM Integrations
• RAG systems
• Claude, GPT & multi-LLM integrations
• n8n AI workflow automation
• Custom AI chatbots & assistants
• AI + backend integration (Spring Boot APIs)
• Document AI (PDFs, invoices, data extraction)
• AI-powered internal tools & dashboards
✔Anti-detect & multi-account specialist, Multilogin developer
• Anti-detect browser & cloud phone setups (Geelark, Adspower, Dolphin anty, More Login etc..)
• 100+ accounts, zero cross-linking
• Fingerprints & proxy configuration
• Account warmup flows
• Secure automation & web scraping
✔How I Work (This is what sets me apart)
• I don’t just code features, I think in systems and long-term impact
• I identify potential issues before they become expensive problems
• I focus on clean architecture, not quick hacks
• I communicate clearly, no confusion, no guessing
• I deliver work that you won’t need to redo later
✔Why clients choose me:
• Clean, maintainable, and efficient code
• Strong focus on performance & scalability
• Clear communication & fast response time
• Reliable delivery, on time, every time
If you’re looking for someone who can build it right the first time, not just “make it work”, let’s talk.
Keywords :
Java, Spring Boot, Spring Security, Hibernate, JPA, REST API, Microservices, RabbitMQ, Azure Service Bus, Angular, Vue.js, React, TypeScript, MEAN stack, MERN stack, full-stack development, JWT, OAuth 2.0, SSO, Azure AD, Keycloak, MySQL, MSSQL, PostgreSQL, MongoDB, database optimization, Docker, AWS, Azure, CI/CD, API integration, LLM integration, RAG, OpenAI API, Claude API, GPT integration, AI chatbot, AI agent, n8n, workflow automation, document AI, PDF extraction, AI automation, LangChain, Multilogin, GoLogin, AdsPower, Dolphin Anty, Octo Browser, Kameleo, antidetect browser, browser fingerprint, anti-detection, residential proxy, mobile proxy, SOCKS5, browser automation, Selenium, Puppeteer, Playwright, web scraping, multi-account automation, account warmup, multi-accounting, ad verification
Spring Security
Java
Hibernate
Spring Data
Spring AMQP
MySQL
Angular
Spring Boot
Selenium
Web Scraping
Puppeteer
Bot Development
Data Scraping
Data Extraction
Automation
API Integration
Web Proxy
Browser Automation
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Summa Linguae
At A Glance: JavaServer Faces (JSF)
Technology is the driving force of the modern world. From Beijing to Seattle, most individuals have hundreds if not thousands of interactions with technology on a daily basis. These interactions can include everything from skimming the morning headlines on a smartphone over breakfast to streaming television from a laptop computer or game console after a day’s work. The majority of modern workplaces, too, are highly dependent upon technology and devices such as computers and their software and applications. Throughout all of these interactions, individuals encounter and rely upon a device or application’s user interface (UI). The UI determines the user’s first impression, as it is the first aspect of an app or piece of software with which they interact. A well-designed user interface can make all the difference in determining the success of an app, particularly considering the fact that consumers often formulate opinions of applications within a few seconds. A UI expert, such as a JavaServer Faces (JSF) specialist, can create a dynamic user interface that will help your business attract new clientele and ensure loyal patrons stay satisfied. JSF is used for building component-based UIs for web applications, and makes it possible to create rich and easily accessible user interfaces. JSF also supports multiple output formats, meaning it’s quite versatile and adaptable.
An expert in JSF, such as those you’ll find on Upwork, can assist you in developing a unique and innovative user interface that will help your business keep in step with ever-evolving technological trends.