1.Engineered a robust console-driven application designed to parse JSON files containing City and Country objects, leveraging XML file formats to generate comprehensive statistics based on user-defined attributes. Employing advanced parallel stream processing techniques, the application efficiently processed over a 1000000 JSON objects within minutes, optimizing memory utilization by eliminating the need for entire data loading into RAM.2. Crafted a REST application that works with country and city entities. It provides CRUD methods and some additional methods for the city entity to upload JSON files or to get Pages or CSV files using HTTP. It uses Docker Compose to start the Postgres database before starting the application and Liquibase to create the schema. Additionally, the application sends messages via RabbitMQ to another microservice.3. Enhanced the Front-End of a Java microservice with ReactJS. Upgraded the existing application by adding functionality to view and modify country and city entities. Integrated the front end seamlessly with the Backend microservice and enabled the local version with Redux.4. Programmed a TypeScript NodeJS microservice to enhance my Java Microservice with third Entity relation. The app uses MongoDB to save data.5. Developed an application designed to receive messages from RabbitMQ and send them via SMTP using Gmail. It retries sending all failed messages every 5 minutes. The application saves email messages in ElasticSearch db and provides Kibana UI.