Position: Java Developer
Category: Java
English level: upper
Years of experience: 5

Software Engineer at Inango: 
- Implemented database migrations for PostgreSQL and MongoDB, simplifying testing and development by allowing developers to modify the database structure and content in an automated manner.

PRRO Project:
- Improved data accuracy by transitioning from double to BigDecimal data types to store prices of goods in receipts and funds in cash desks. Implemented MongoDB migrations to update the data type and round their values in the database, ensuring precise financial records.

Service for Buying Fuel:
- Expanded payment options by integrating Vostok Bank, Concord Bank, Portmone. Implemented a convenient feature enabling users to save their payment card information for future orders, streamlining the checkout process.
*Software Engineer at Inango*
- Implemented a Quality of Service (QoS) service to detect the traffic of configured applications and prioritize their traffic based on dynamic settings.
- Developed a DNS name-based parental control service with F-Secure integration.
- Upgraded Spotify's deprecated docker-client to docker-java, ensuring continued support and stability for our container management.
- Introduced a feature for transferring docker container logs to the web via websocket.
- Replaced RabitMQ with gRPC for sending traffic packets, resulting in increased bandwidth due to the higher performance of gRPC.
- Engineered a comprehensive statistics collection system, which included calculation and aggregation by specified periods to enhance the speed of display on the web.
- Conducted thorough code reviews and executed unit and integration tests to ensure product quality.

*Freelance experience:*
**PRRO Project (eng. Programmatic Recorder of Payment Transactions, ukr. Програмний реєстратор розрахункових операцій)
- Expanded functionality by introducing new operations, including the ability to view cash register transactions, send Z reports, and manage cash registers. This included tasks such as registration, updating information from the tax office, and more.
- Meticulously addressed and resolved various software bugs, contributing to the stability and reliability of the PRRO project.

**Service for Buying Fuel
- Implemented the capability to authorize requests using bearer tokens.
- Managed MySQL database migration using Flyway.
- Introduced the ability to generate new fuel coupons with underfilled fuel when using a fuel coupon for payment. Additionally, added fuel purchases using these generated coupons at the same petrol station.
- Added user registration with mobile phone and email confirmation.
- Enabled users to access their transaction history.
- Implemented a geolocation-based service that allows users to search for the nearest gas stations based on their coordinates, displaying the distance to each station.