Hire the Best Enterprise JavaBeans (EJB) Specialists
in Poland

Over the last 15 years, I have developed a wide range of applications using Java technologies. Spring / Spring Boot, Hibernate JSP, JSF, Apache Wicket, Apache Struts HTML.CSS, JavaScript, jquery, mySql, postgreSQL, Oracle. My skills are confirmed by certifications: VMWare Spring Certified Profesional OCP (Oracle Certified Professional Java SE 17) SCJP (Sun Certified Java Programmer) SCWCD (Sun Certified Web Component Developer).

⭐ Designed and implemented systems handling 10,000+ requests per second. ⭐ Played a key role in a tech stack migration that resulted in annual savings of up to $450,000 for the client. ⭐ Delivered the client's flagship product ahead of schedule, resulting in faster time-to-market and a competitive advantage. ⭐ Improved performance by analyzing query plans and optimizing slow queries. Over 15 years of experience in software development, with 5+ years specializing as a Solution Architect. Expertise in Java and the Spring Framework as the primary technology stack, with extensive hands-on experience and a deep passion for Java development. ✅ Skilled in developing technical roadmaps, making critical technical decisions, system design, project estimation, and effective stakeholder communication. ✅ Languages: Java 8-21, JavaScript, TypeScript, Python. ✅ Spring Ecosystem: Spring Boot, Spring MVC, Spring Data JPA, Spring Security, Spring Cloud (Config, Gateway, Eureka), Spring WebFlux. ✅ ORM: Hibernate, EclipseLink, MyBatis. ✅ Message Brokers: RabbitMQ, Google Cloud Pub/Sub, Apache Kafka, IBM MQ, ActiveMQ. ✅ Databases: Oracle, Microsoft SQL Server, PostgreSQL, MySQL, MongoDB, Firebase, Cassandra, Aerospike, Redis, ElasticSearch. ✅ Strong background in Fintech, Social Networks, Logistics & Transportation, and Tourism & Hospitality industries.

Hey👋 == 𝟮𝟮 𝘆𝗲𝗮𝗿𝘀 𝗼𝗳 𝗫𝗣. 𝟭𝟕𝟬 𝗽𝗿𝗼𝗷𝗲𝗰𝘁𝘀. 𝟭𝟬𝟬% 𝘀𝘂𝗰𝗰𝘀𝗲𝘀 𝗿𝗮𝘁𝗲. == ✔𝐅𝐫𝐞𝐞 𝟐𝟎 𝐡𝐨𝐮𝐫𝐬 𝐨𝐟 𝐩𝐥𝐚𝐧𝐧𝐢𝐧𝐠 𝐟𝐨𝐫 𝐲𝐨𝐮𝐫 𝐧𝐞𝐰 𝐩𝐫𝐨𝐣𝐞𝐜𝐭 (DM "Free") ✔𝐅𝐫𝐞𝐞 𝐜𝐨𝐝𝐞 𝐫𝐞𝐯𝐢𝐞𝐰 𝐟𝐨𝐫 𝐲𝐨𝐮𝐫 𝐞𝐱𝐢𝐬𝐭𝐢𝐧𝐠 𝐩𝐫𝐨𝐣𝐞𝐜𝐭 (DM "Free") Main focus: ✅𝐑𝐞𝐥𝐢𝐚𝐛𝐢𝐥𝐢𝐭𝐲 𝐞𝐧𝐠𝐢𝐧𝐞𝐞𝐫𝐢𝐧𝐠: structured review of your application, architecture, AWS infrastructure, deployment process, monitoring, and operational dependencies, followed by a prioritized remediation roadmap. ✅𝐏𝐎𝐒 𝐚𝐧𝐝 𝐌𝐮𝐥𝐭𝐢-𝐒𝐭𝐨𝐫𝐞 𝐂𝐨𝐦𝐦𝐞𝐫𝐜𝐞: POS, KDS, checkout, payment, catalog, ordering, inventory, loyalty, reporting, and multi-store commerce software for businesses operating across physical locations and online storefronts. ✅𝐈𝐨𝐓 𝐅𝐥𝐞𝐞𝐭 𝐌𝐚𝐧𝐚𝐠𝐞𝐦𝐞𝐧𝐭: build secure IoT, telemetry, remote diagnostics, and predictive maintenance platforms for manufacturers, service teams, and operators managing connected devices at scale. ✅𝐉𝐚𝐯𝐚 𝐄𝐜𝐨𝐬𝐲𝐬𝐭𝐞𝐦 𝐌𝐨𝐝𝐞𝐫𝐧𝐢𝐳𝐚𝐭𝐢𝐨𝐧: modernizes Java-based enterprise systems in controlled stages, including EJB applications, Oracle products, application servers, while preserving critical business functionality. ✅𝐄𝐧𝐭𝐞𝐫𝐩𝐫𝐢𝐬𝐞 𝐒𝐨𝐟𝐭𝐰𝐚𝐫𝐞 𝐑𝐞𝐬𝐜𝐮𝐞: help companies take over, understand, stabilize, and safely continue development of complex Java, Spring, and AWS systems when the existing team, architecture, or delivery process is no longer reliable. ================================================ WE EARN/SAVE MONEY💰 FOR OUR CUSTOMERS by: • allowing their business to expand (or start sometimes:) • automating processes and reducing operational cost • using newer and more efficient technology • long-run cost reduction because of high-quality software. ================= Some tech below =============== ✔ Cloud applications Cloud, serverless, scalable applications, architecture and development for Amazon Web Services (AWS) and Google Cloud Platform (GCP). ✔ AI development and integration Embed AI-powered tools to your business and software: AI analytics, predictive maintenance, LLM, chatbots, ChatGPT integration, AI over your data helping your clients. ✔ Complex system development, API integration and development Develop custom software from A to Z, build sophisticated APIs, integrate third-party APIs, data hubs and gateways. ✔ Big data volumes processing, storage, and analytics Receive, process, store and analyze and send huge volumes of data. Cost-efficient data-focused systems on the cloud. ✔ Internet of things (IoT) Connect and manage thousands of simple and complex devices on the cloud, custom automation, reports and analytics. ✔ Other Workflow automation, Performance optimization, QA automation. Some tech details: ✓ Java/Spring: SpringBoot/Spring Cloud/Spring Web/Spring AI/Spring Security/Spring Data etc. ✓ Java/JavaEE: EJB, JSP/JSF/RichFaces/Oracle ADF, JavaFX ✓ Spring: SpringBoot, Spring MVC, Web, Security, Data, AI ... ✓ Cloud: AWS, Google Cloud, Docker, Kubernetes, ECS, EKS, Cloud-native apps, scalable clusters, zero-downtime deployment. ✓ AI: Codex, Claude, MCP, RAG, Vertex AI. ✓ Databases: Oracle/PostgreSQL/MySQL, PL/SQL, AWS RDS, big volume storage (AWS Redshift, AWS Athena/S3, Aurora, Cassandra, HDFS), Redis, MongoDB, Neo4j, S3/Parquet, JPA, custom ORMs. ✓ Web: Bootstrap, Angular, React, JavaScript, OAuth. ✓ Servers: Tomcat, Weblogic, JBoss/Wildfly, Websphere. ✓ APIs: REST, SOAP, XML-RPC, WebServices, WebSockets, Swagger/OpenAPI. ✓ AWS: Clusters, AWS EC2, AWS Kinesis, AWS Athena, AWS Redshift, AWS DynamoDB, AWS Lambda, AWS IoT, AWS SQS/SNS, AWS CloudFront/Route53/ApiGateway, vast AWS API usage, and automation. ✓ Data streaming: AWS Kinesis, Firehose, SQS/SNS, Kafka, Camel, RabbitMQ. ✓ Performance optimization: JMeter, JProfiler, AWS X-Ray, GTMetrix, Gatling. ✓ Version control: Git, Github, Bitbucket, GitLab, SVN. ✓ CI/CD: Bamboo, Jenkins, Circle CI, Sonar, Bitbucket pipelines, GitHub Actions, AWS CodeBuild/CodeDeploy. ✓ Other: Maven, Nexus, Gradle, Ant. We get things done.

Experienced backend Java developer with over a decade of expertise in developing and maintaining high-quality software solutions. My career includes roles at Accenture, Credit Suisse and GFT Group. Based in Poland, I have also worked in London with Luxoft and Unibet, a leading company in the gambling industry. Top-rated Upwork freelancer, ranked in the top 5% of performers with a 100% Job Success Score. Proficient in Java, Spring Boot, REST APIs, and cloud technologies (AWS). Adept at working with distributed international teams, emphasizing clean code practices and delivering challenging projects. Programming Languages: Java, JavaScript, Scala APIs & Integrations: RESTful APIs, GraphQL, WebSocket, RabbitMQ, JMS, Kafka Cloud & DevOps: AWS (Cloudformation), Docker, CI/CD (Jenkins, GitHub Actions) Frameworks & Tools: Spring Framework, Spring Boot, Hibernate, JPA Version Control: Git, GitLab, Bitbucket Databases: MySQL, PostgreSQL, MongoDB, Redis Testing: JUnit, Mockito, Cucumber, TDD Others: Observability, Keycloak, Angular, Maven, Bash

Hello👋 Are you looking for experienced and certified Java engineers to boost your project? You are on the right page! Clear Solutions team provides Java engineers and grows their skills for you. We have more than 12 years of experience in IT and 8+ in Java. My team and I are happy to provide: 🚀 Java developers with transparent knowledge for transparent rates 🚀 People development services: technical assessments, mentoring, evaluation etc. Based on more than 500 interviews and technical assessments we made in the industry so far we created our own evaluation scale. Therefore you always know what set of knowledge you pay for each grade. Do you feel this is what you need? Let's schedule a quick call and find out how we could help you to grow ✅ I have an experience in the following: 👉 migration from on prem to AWS 👉 building microservce architecture from scratch 👉 delivering robust and high-quality code with unit tests 👉 building java high-load and distributed applications 👉 migration from monolith to microservices 👉 building the right engineering culture inside the company 👉 mentoring technical leaders Tech Stack: 🔹 Languages: Java 8, Java 16, Groovy. Spring boot, RESTful API, DB design, 🔸 Frameworks: Spring, Spring Boot, Hibernate, Spring Data 🔹 Clouds: AWS 🔸 SQL: PostgreSQL, MariaDB, Oracle 🔹 NoSQL: Elasticsearch, Redis, MongoDB, Cassandra, DynamoDB 🔸 Message brockers: Apache Kafka or RabbitMQ 🔹 Testing: Junit5, Testcontainers, Spock, RestAssured We have expertise in the following fields: ✅ FinTech, ✅ Trading, ✅ Cryptocurrency, ✅ Banking, ✅ Data processing, ✅ Healthcare, ✅ Social Networking and more. Do you feel this is what you need? Let's schedule a quick call and find out how we could help you to grow As a Backend Developer, I specialize in building robust Java Applications using Core Java, Spring Framework, and Spring Boot 3, leveraging tools like Maven, Gradle, and Bazel for efficient builds, and integrating Hibernate, JPA, and Apache POI for database and document handling. I have extensive experience with RESTful Architecture and SOAP for designing APIs, ensuring Application Security, and implementing testing frameworks like JUnit, JUnit5, Mochito, and AssertJ. I work across diverse environments, including Docker, AWS, Amazon Elastic Beanstalk, AWS Lambda, Google Cloud, and Azure (Azure Cosmos DB), utilizing databases like PostgreSQL, MySQL, MongoDB, Oracle Database, Microsoft SQL Server, IBM Db2, and RabbitMQ. On the frontend, I use HTML, CSS, JavaScript, TypeScript, Angular, AngularJS, and React, collaborating seamlessly using tools like Jira. For messaging and event-driven architecture, I rely on Apache Kafka, Apache ActiveMQ, and RabbitMQ, and for advanced testing, I employ Testcontainers. With a focus on Software Architecture & Design, I also develop Standalone Applications, Desktop Applications, and Web Services, ensuring scalable, secure solutions for enterprise systems and Microservices Architecture.