I am a Senior Software Engineer with 14+ years of experience delivering scalable, secure, and high-performance digital solutions. My expertise spans backend development, web applications, APIs, data pipelines, cloud engineering, and enterprise IT services across industries such as e-commerce, finance, healthcare, and SaaS. 🔹 Core Expertise * Backend Development (Java & Python): Microservices, server-side logic, authentication, caching, queue systems, and performance-driven architectures. * API Development & Integrations: REST, GraphQL, third-party integrations, payment gateways, system-to-system communication, and secure API design. * Web & Enterprise Applications: Custom web apps, SaaS platforms, CRM/CMS systems, admin dashboards, business automation tools. * Data Engineering & Optimization: ETL pipelines, data workflows, analytics automation, database tuning, and high-volume data processing. * Cloud & DevOps Services: AWS/GCP deployments, Docker, Kubernetes, CI/CD pipelines, server optimization, and infrastructure setup. * System Modernization & Performance Tuning: Refactoring legacy systems, improving reliability, scaling for growth, and reducing server load & query response time. 🔹 Professional Strengths * Strong problem-solving for complex backend and data workflows * Delivering clean, maintainable, and well-structured code * Transparent communication and consistent updates * Ability to handle end-to-end development, from architecture to deployment * On-time delivery with a focus on quality, scalability, and security 🔹 What You Can Expect Working With Me Whether you need a backend expert, a full IT services partner, or someone to improve/modernize existing systems — I bring deep technical expertise, business understanding, and reliable execution to every project. If you’re looking for a trustworthy senior engineer who can build, optimize, and scale your digital products, I’d be happy to collaborate. Let’s connect and create a solution that drives real results for your business.

🏆 TOP RATED PLUS ON UPWORK 🥇 Liferay Certified Developer & Consultant 🥇 Sun Certified Java Developer 🥇 IBM Certified WebSphere Portal Solution Developer 💯 100% Job Success Rate ⌛ 17,000+ Hours Delivered on Upwork 🚀 20+ Years of Enterprise Software Experience Organizations using Liferay need reliable experts who can modernize digital platforms, build scalable enterprise portals, integrate business systems, and leverage modern technologies like AI to improve user experience and operational efficiency. As a Liferay Certified Developer and Consultant with 20+ years of enterprise software experience, I help businesses design, customize, upgrade, migrate, and enhance Liferay DXP solutions from enterprise portal implementations and complex integrations to AI-powered features, automation, performance optimization, and long-term support. I have delivered enterprise solutions across Healthcare, Ecommerce, Manufacturing, Travel & Hospitality, Education, Real Estate, Retail, and other industries. Liferay DXP Expertise ✔ Liferay DXP 7.x Development & Customization ✔ Latest Liferay DXP Version Implementations ✔ Liferay Portal Development ✔ Liferay Upgrade & Migration ✔ Legacy Liferay Modernization ✔ Custom OSGi Module Development ✔ Portlet Development ✔ Theme & UI Customization ✔ Workflow Automation ✔ CMS Customization ✔ Roles, Permissions & User Management ✔ Liferay Performance Optimization ✔ Elasticsearch Integration & Intelligent Search Enhancement AI & Modern Digital Experience Solutions ✔ AI Integration with Enterprise Applications ✔ Generative AI Integration ✔ AI-powered Portal Features ✔ AI Chatbots and Virtual Assistants ✔ Enterprise Knowledge Search using AI ✔ LLM-based Application Integrations ✔ AI Automation for Business Workflows ✔ Intelligent Content and User Experience Enhancements Portal Solutions Building and improving: ✔ Customer Portals ✔ Partner Portals ✔ Vendor/Supplier Portals ✔ B2B Portals ✔ Self-Service Portals ✔ Enterprise Intranet Solutions Liferay Integration Expertise ✔ Single Sign-On (SSO) ✔ LDAP Integration ✔ Keycloak Integration ✔ OAuth / OpenID Connect ✔ REST API Integrations ✔ Third-Party Enterprise System Integrations ✔ ERP, CRM and Business Application Integrations Java & Enterprise Development ✔ Java / J2EE ✔ Spring Framework ✔ Spring Boot ✔ Spring Security ✔ Hibernate ✔ REST Services ✔ Microservices Architecture Cloud & DevOps ✔ AWS / Azure Deployments ✔ Docker & Kubernetes ✔ CI/CD Pipelines ✔ Application Server Configuration ✔ Production Support & Optimization How I Help Clients ✔ Build new Liferay enterprise portals ✔ Upgrade and migrate existing Liferay platforms ✔ Customize portal workflows and business features ✔ Integrate Liferay with enterprise systems ✔ Add AI capabilities to digital platforms ✔ Improve portal performance and scalability ✔ Provide ongoing Liferay support and maintenance My focus is not only writing code, but helping organizations create scalable, intelligent, and future-ready digital platforms that support business growth and operational efficiency. If you need a Liferay expert for development, migration, consulting, AI integration, or long-term support, I can help.

I have worked on various web projects as fullstack developer. Main stack: ML/AI frameworks such as TensorFlow and PyTorch, Ruby on Rails, Ruby, ReactJs, NextJs, DevOps. Tailwind CSS, Twitter Bootstrap, HTML, CSS, My SQL, PostgreSQL, AWS, CoffeeScript

Full stack developer with Java expertise. I am a full-stack developer (Backend expertise ) with more than around 7 years of experience in building web apps using Java, Spring boot, Hibernate, MongoDB, MySQL, ElasticSearch, Redis, Queues like Kafka/RabbitMQ. I have developed various enterprise microservices applications which were meant to be scalable and performance intensive. I'm fluent in English.I'm passionate about web technologies, therefore, whatever I do I try to deliver my best and try to learn new things every day. Please send me a message if you building something awesome. I can complete your project successfully with my skills and experience. Expert in the following areas: Backend: Java Angular Technologies and Frameworks: Spring Boot Spring AOP Blockchain(Crypto currency) JPA & Criteria API REST Services GCM(Google Cloud Messaging) Firebase Messaging Websockets Integration with external systems: Twitter, Google, Facebook, SendGrid. Application/Web Servers: Tomcat Cache: Redis. Messaging Systems: Apache Kafka, RabbitMQ. Event Streaming: Kafka Streaming. Databases: MySQL MongoDB ElasticSearch. Database Access: JDBC Spring(JDBCTemplate, HibernateTemplate, JpaTemplate) Spring Data Mybatis. Front-end programming: HTML CSS3 Javascript Angular 6 Websockets(STOMP) Bootstrap. Version control system: Git, SVN. Have experience with Agile and Scrum methodologies.

Hi there 👋, I’m Peter. I help startups and businesses build reliable, scalable backend systems using Golang. With 14+ years of software development experience, including 8+ years specializing in Go, I’ve designed and developed production systems used by companies across cybersecurity, fintech, cloud printing, e-commerce, and data platforms. Whether you need a new backend service, REST API, microservice, third-party integration, automation tool, or performance optimization, I focus on delivering clean, maintainable code that is built for production, not just proof of concept. What I can help you with ✅ Golang Backend Development ✅ REST APIs & gRPC Services ✅ Microservices Architecture ✅ Third-party API Integrations ✅ PostgreSQL, MySQL & MongoDB ✅ Redis & Kafka ✅ Docker & Kubernetes ✅ AWS Cloud Services ✅ Performance Optimization ✅ Backend Automation ✅ System Design Why clients work with me I believe great backend software should be: * Reliable * Scalable * Easy to maintain * Well tested * Easy for other developers to understand I communicate clearly, work independently, take ownership, and always aim to deliver solutions that continue to add value long after the initial implementation. Technologies: Programming Languages: Go (Golang) (Primary), Java, Python, JavaScript, Shell Scripting, Node.js, PHP Backend Engineering: Microservices, Distributed Systems, RESTful APIs, gRPC, Event-Driven Architecture, Serverless, Concurrent Programming Cloud Platforms: AWS (Lambda, EC2, S3, Cognito, DynamoDB, SNS, SQS, CloudWatch, CDK, EMR), DigitalOcean Databases & Caching: PostgreSQL, MongoDB, MySQL, Redis, Cassandra, HBase, SQL, NoSQL Messaging & Distributed Systems: Kafka, RabbitMQ, Hadoop, MapReduce, YARN, ZooKeeper DevOps & Infrastructure: Docker, Kubernetes (Basic), GitHub Actions, Jenkins, GitLab CI, Ansible, Git Observability: Prometheus, Grafana, ELK Stack (Elasticsearch, Logstash, Kibana), AWS CloudWatch Software Engineering: System Design, CI/CD Pipelines, Test-Driven Development (TDD), Agile, Scrum, Code Reviews, Data Structures & Algorithms Frontend (Working Knowledge): Angular, TypeScript, HTML, CSS, Flutter, Figma If you’re looking for an experienced backend engineer who can quickly understand your requirements and build production-ready Go applications, I’d be happy to discuss your project.

I am working in the IT industry since 8 years. I have experience of working on medium to large scale applications My main skill set comprises of 1) Java 8 2) Spring Boot 3) Micro service architecture 4) Service discovery (Consul , Eureka , Zookeeper) 5) API Gateway (Zuul) 6) Batch processing 7) Elastic, Cassandra, Solr, Mongo DB Atlas, mySql 8) JPA, Quartz, ActiveMq , Keycloak, XMPP 9) Maven,Sonar,Docker, Circuit breaker 10) AWS, GCP 11) KeyCloak

I have 8+ years of experience in consulting and developing Web applications. As a full-stack developer, I assist clients in transforming their ideas into a complete product. I can consult, build, set up, and maintain web applications, particularly in the Open-Source domain. Why me? ------------------------------------------------------------------------------------- *24*7 Availability @skype *100% Bug-Free Code *Provide High-Quality Services *Good Listener and Good Communication Skills. *Use Latest IDEs for Development. *Free 180 Days Support after Completing the Project/Assignment. ---------------------------------------------------------------------------------- I have experience with the following technologies: - React.js/Angular.js - Python/Django, - GraphQL - API (REST framework) - Flask - Elasticsearch - Data scraping - MySQL, PostgreSQL, SQLite - HTML/CSS (HTML5/CSS3) - JavaScript, jQuery (Bootstrap, Foundation, SASS, LESS) - Unix, Mac, Windows operating systems I like to be involved in the full life-cycle of the project, from requirement analysis, initial design, and implementation through to deployment and production support

Hi, I'm an experienced senior backend Developer, and I'm very interested in PHP and Symfony Framework. I have consistently delivered projects on time and under budget. I am available to chat by IM, email and would be happy to set up a convenient time to discuss the application you're moving to and some ideas.

I'm a proficient data application engineer with 10+ years of working experience and a strong command of Java. I've built robust big data platforms using technologies such as Hadoop, Hive, Doris, and Flink. Specializing in Java web applications, I excel in frameworks such as Spring Boot and JPA.

🥇Expert-Vetted (Top 1% on Upwork) 📈 500+ hours ⭐5-Star ratings across all projects 💼 10+ years of experience. I DO NOT use any AI coding tools in my work. No I am not a dinosaur. For me it is faster to write the code down nigher to express to llm what I need and how to do it and then fix it errors. In a day when it chamges there will be no need for software developers, for software engineers maybe. I can use llm when I generate tests (works good as skeleton for boilerplate coding) or when I am working with frontend. One langue to another convertor is also a good tool. I'm an experienced Backend Software Development Engineer, and LLM researcher and have experience in working at some of the best AI labs in the world. During my tenure at Microsoft AppCenter, I successfully deployed ML models into production using Azure ML and designed highly scalable APIs in Python, C, and C++. My code is instrumental in facilitating over a hundred thousand tests daily on real hardware for Android and iOS devices. Before that, I worked on various Python/NodeJS projects. Now as a lead developer or a team lead or an individual freelancer I am helping startups to rock the thing! Overcoming completes with building high advanced systems and bringing AI revolution closer. Some of the feedback given by customers across the world: - Kirill is absolutely best freelancer I worked with... - Working with Kirill was a fantastic experience. He was insightful and helpful in all aspects of the development process... - Rockstar! ... Hardcore Linux nerd, 15 years with Linux as my main OS on my workstation. PostgreSQL evangelist. And believing that mobX can save the world. Are you ready to apply high-quality AI in your company? If you're looking for a quality professional, feel free to drop a line! When you invest in my services, you're not just hiring a developer - you're partnering with a strategic technology advisor who bridges the gap between AI capabilities and real business results. My track record speaks for itself through consistently exceptional client reviews.