Yurii Serheiev Email & Phone Number

Participated in development and maintenance of a Financial SaaS application, which calculates payroll, generates and sends tax reports, and manages the employee database. My major achievements:● Automated processing and exchange of tax documents with the tax office was developed and implemented, which saved ~70% of the accounting department’s time.● Optimized the PostgreSQL DB structure, refactored legacy code and implemented caching using Redis (Elasticache) as a result the selection of frequently repeated queries was accelerated by ~97 times.● Developed an authentication and authorization service.● Reconfiguret AWS cloud infrastructure to reduce 30% of monthly cost.

Development, maintenance and refactoring of (legacy) enterprise applications for several clients:● Implemented two-factor authentication by scanning a QR code in Google Authenticator using TOTP and JWT. Implemented SSO using OAuth2 + Keycloak.● Developed multi-threaded document importing service from XML and CSV and exporting to PDF and Excel.● Developed a service for sending messages with attachments via SOAP (JAX-WS, MTOM) and JMS with ActiveMQ.● Developed data storage in SQL/NoSQL databases based on Spring JBDC, Hibernate and Spring Data JPA and database migration using Liquibase.

Kyiv, Ukraine

Engaged in the research, development, and support of e-commerce solutions:● Assembled a team of 13 people (2 UI/UX designers, 3 Backend developers, 2 SEO & Google Ads Specialists, 2 Content managers, 2 - 1C Accounting Developers, 1 accountant, 1 System administrator) from 3 countries.● Developed and supported 7 commercial projects with metrics collection, banking and messaging integrations, warehouse management, accounting, etc.

Kyiv, Ukraine

Development of Websites and E-commerce solutions for corporate clients. Integration and maintenance of the company's local 1C system for warehouse management and accounting. Utilizing the following technologies: PHP, CodeIgniter, Ajax, JQuery, Bootstrap, HTML5, CSS, HTTP/HTTPS, REST, MySQL, and Apache HTTP Server, 1C:● Developed and launched my own CMS (content management system) on PHP.● Developed and maintained more than 30 websites and online stores.

Kyiv, Ukraine

Administration of databases and computer networks in a company that was engaged in wholesale supplies of raw materials for light industry:● Deployment of two office networks with 50+ workstations in each and connecting them via VPN using Windows Server (Active Directory), MS SQL Server, OpenVPN.● Optimized logistics processes, which reduced downtime and increased turnover by 4 times.

Kyiv, Ukraine

Participating in the development and testing of software for metal heat treatment processes. Tech stack included: Delphi (6-8), Pascal, Java (1.2-5), C++, PHP, JavaScript, MySQL, HTML, CSS, XML, Ajax. And my achievements included:● Took part in the development of 2 calculation programs. Completely developed and launched the official website of the company.● Took part in writing scientific materials, editing materials and collecting data from scientific experiments.

Kyiv, Ukraine

Development and implementation of network solutions to support the university’s intranet:● Install and configure network equipment to ensure optimal performance, reliability, and security of networks.● Maintaining network infrastructure for 13 faculties and 9 institutes. This included regular updates and troubleshooting as needed.