Available to hire
Hi, I’m Illia, a Backend Developer with over 6 years of experience building scalable and efficient web applications. I specialize in JavaScript and TypeScript, primarily working with Node.js frameworks like Express and NestJS. I enjoy solving complex problems, designing APIs, and working in collaborative, multinational teams.
I’m passionate about continuous learning and staying updated with the latest technologies to create reliable and high-performance systems. When I’m not coding, I like mentoring junior developers and improving workflows to build better software together.
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Language
English
Intermediate
Belarusian
Fluent
Russian
Fluent
Polish
Intermediate
Work Experience
Full Stack Developer at Bayer, Warsaw
February 1, 2023 - June 1, 2024Developed and maintained large-scale applications with complex hierarchical structures using Node.js, PostgreSQL, and React, handling over 1 million requests per week. Integrated frontend and backend components for seamless user experiences. Developed and maintained RESTful and GraphQL APIs, including third-party service integrations. Designed, optimized, and maintained relational and NoSQL databases. Performed unit, integration, and end-to-end testing; efficiently debugged complex issues. Ensured high code quality, readability, and long-term maintainability through best practices and code reviews. Collaborated in multinational teams across Europe and North America. Managed data migration from legacy databases to new systems preserving data integrity. Worked with AWS tools including ECR, RDS, Redis, Lambda, and Service Catalog.
Backend Developer at Itransition Group, Minsk
October 1, 2021 - February 1, 2023Developed and maintained scalable RESTful and GraphQL APIs. Designed system architecture with focus on scalability and maintainability. Integrated new features and implemented complex business logic. Optimized system performance and routing to improve speed and efficiency. Leveraged AWS services including Service Catalog, ECR, Redis, RDS, and Lambda for infrastructure and deployment. Mentored junior developers and collaborated with international teams across Europe, North America, and Asia.
Backend Developer at Knomary, Minsk
February 1, 2020 - October 1, 2021Optimized application architecture to facilitate efficient workflow. Implemented and tested new features contributing to platform evolution. Authored comprehensive test suites to ensure application reliability. Mentored junior team members fostering a supportive environment. Addressed and resolved software bugs to maintain high-quality standards. Created database from scratch and defined relationships between entities.
Software Engineer at Lamplighter, Minsk
July 1, 2019 - February 1, 2020Contributed to architectural improvements and feature expansions. Led stylization of new web pages ensuring consistency and responsiveness. Maintained legacy styles for backward compatibility. Developed unit tests using Jest and fixed bugs in backend services. Participated in Agile ceremonies.
HTML Game Engineer at Playgendary, Minsk
January 1, 2019 - June 30, 2019Improved architectural implementation, added new features and functionality. Worked with Canvas, Phaser, and Cocos. Developed game advertising logic including Playable Ads. Communicated with technical specialists from other teams.
Full Stack Developer at Bayer, Warsaw
February 1, 2023 - June 5, 2024Developed and maintained large-scale applications with complex hierarchical structures using Node.js, PostgreSQL and React, handling over 1 million requests per week. Integrated frontend and backend components for seamless user experiences. Developed and maintained RESTful and GraphQL APIs, including third-party service integrations. Designed, optimized, and maintained relational and NoSQL databases. Performed unit, integration, and end-to-end testing; efficiently debugged complex issues. Ensured high code quality, readability, and long-term maintainability through best practices and code reviews. Collaborated in multinational teams across Europe and North America. Managed data migration from legacy database to new system while preserving integrity. Worked with a range of AWS tools including ECR, RDS, Redis, Lambda, and Service Catalog.
Backend Developer at Itransition Group, Minsk
October 1, 2021 - February 1, 2023Developed and maintained scalable RESTful and GraphQL APIs. Designed system architecture with a focus on scalability and maintainability. Integrated new features and implemented complex business logic. Optimized system performance and routing to improve speed and efficiency. Leveraged AWS services including Service Catalog, ECR, Redis, RDS, and Lambda for infrastructure and deployment. Mentored junior developers and collaborated with international teams across Europe, North America, and Asia.
Backend Developer at Knomary, Minsk
February 1, 2020 - October 1, 2021Optimized application architecture to facilitate efficient workflow. Implemented and tested new features, contributing to the platform's evolution. Authored comprehensive test suites to ensure application reliability. Mentored junior team members, fostering a supportive environment. Addressed and resolved software bugs to maintain high-quality standards. Created database from scratch and defined relationships between entities.
Software Engineer at Lamplighter, Minsk
July 1, 2019 - February 1, 2020Contributed to architectural improvements and feature expansions. Led the stylization of new web pages, ensuring consistency and responsiveness. Maintained legacy styles, ensuring backward compatibility. Developed unit tests using Jest and fixed bugs in backend services. Participated in Agile ceremonies.
HTML Game Engineer at Playgendary, Minsk
January 1, 2019 - June 30, 2019Improved architectural implementation. Added new features and functionality. Worked with Canvas, Phaser, and Cocos. Wrote logic and developed game advertising (Playable Ads). Communicated with technical specialists from other teams.
Full Stack Developer at Bayer, Warsaw
February 1, 2023 - June 21, 2024Developed and maintained large-scale applications with complex hierarchical structures using Node.js, PostgreSQL and React, handling over 1 million requests per week. Integrated frontend and backend components for seamless user experiences. Developed and maintained RESTful and GraphQL APIs, including third-party service integrations. Designed, optimized, and maintained relational and NoSQL databases. Performed unit, integration, and end-to-end testing; efficiently debugged complex issues. Ensured high code quality, readability, and long-term maintainability through best practices and code reviews. Collaborated in multinational teams across Europe and North America. Data migration from legacy database to new system with integrity preserved. Worked with a range of AWS tools including ECR, RDS, Redis, Lambda, and Service Catalog.
Backend Developer at Itransition Group, Minsk
October 1, 2021 - February 1, 2023Developed and maintained scalable RESTful and GraphQL APIs. Designed system architecture with a focus on scalability and maintainability. Integrated new features and implemented complex business logic. Optimized system performance and routing to improve speed and efficiency. Leveraged AWS services including Service Catalog, ECR, Redis, RDS, and Lambda for infrastructure and deployment. Mentored junior developers and collaborated with international teams across Europe, North America, and Asia.
Backend Developer at Knomary, Minsk
February 1, 2020 - October 1, 2021Optimized application architecture to facilitate efficient workflow. Implemented and tested new features, contributing to the platform's evolution. Authored comprehensive test suites to ensure application reliability. Mentored junior team members, fostering a supportive environment. Addressed and resolved software bugs to maintain high-quality standards. Created database from scratch and defined relationships between entities.
Software Engineer at Lamplighter, Minsk
July 1, 2019 - February 1, 2020Contributed to architectural improvements and feature expansions. Led the stylization of new web pages, ensuring consistency and responsiveness. Maintained legacy styles, ensuring backward compatibility. Developed unit tests using Jest and fixed bugs in backend services. Participated in Agile ceremonies.
HTML Game Engineer at Playgendary, Minsk
January 1, 2019 - June 30, 2019Improved architectural implementation. Added new features and functionality. Worked with Canvas, Phaser, and Cocos. Wrote logic and developed game advertising (Playable Ads). Communicated with technical specialists from other teams.
Full Stack Developer at Bayer
February 1, 2023 - June 14, 2024Developed and maintained large-scale applications with complex hierarchical structures using Node.js, PostgreSQL, and React, handling over 1 million requests per week. Integrated frontend and backend components for seamless user experiences. Developed and maintained RESTful and GraphQL APIs, including third-party service integrations. Designed, optimized, and maintained relational and NoSQL databases. Performed unit, integration, and end-to-end testing; efficiently debugged complex issues. Ensured high code quality, readability, and long-term maintainability through best practices and code reviews. Collaborated in multinational teams across Europe and North America. Data migration from legacy database to new system with integrity preserved. Worked with a range of AWS tools including ECR, RDS, Redis, Lambda, and Service Catalog.
Backend Developer at Itransition Group
October 1, 2021 - February 1, 2023Developed and maintained scalable RESTful and GraphQL APIs. Designed system architecture with a focus on scalability and maintainability. Integrated new features and implemented complex business logic. Optimized system performance and routing to improve speed and efficiency. Leveraged AWS services including Service Catalog, ECR, Redis, RDS, and Lambda for infrastructure and deployment. Mentored junior developers and collaborated with international teams across Europe, North America, and Asia.
Backend Developer at Knomary
February 1, 2020 - October 1, 2021Optimized application architecture to facilitate efficient workflow. Implemented and tested new features, contributing to the platform's evolution. Authored comprehensive test suites to ensure application reliability. Mentored junior team members, fostering a supportive environment. Addressed and resolved software bugs to maintain high-quality standards. Created database from scratch and defined relationships between entities.
Software Engineer at Lamplighter
July 1, 2019 - February 1, 2020Contributed to architectural improvements and feature expansions. Led the stylization of new web pages, ensuring consistency and responsiveness. Maintained legacy styles, ensuring backward compatibility. Developed unit tests using Jest and fixed bugs in backend services. Participated in Agile ceremonies.
HTML Game Engineer at Playgendary
January 1, 2019 - June 30, 2019Improved architectural implementation. Added new features and functionality. Worked with Canvas, Phaser, and Cocos. Wrote logic and developed game advertising (Playable Ads). Communicated with technical specialists from other teams.
Education
Bachelor's Degree at Belarusian State University, Mechanics and Mathematics Faculty
January 1, 2011 - December 31, 2016Bachelor's Degree at Belarusian State University, Law Faculty
January 1, 2012 - December 31, 2018Bachelor's degree at Belarusian State University
January 1, 2011 - December 31, 2016Bachelor's degree at Belarusian State University
January 1, 2012 - December 31, 2018Bachelor's Degree at Belarusian State University
January 1, 2011 - December 31, 2016Bachelor's Degree at Belarusian State University
January 1, 2012 - December 31, 2018Bachelor's at Belarusian State University
January 1, 2011 - December 31, 2016Bachelor's at Belarusian State University
January 1, 2012 - December 31, 2018Qualifications
JavaScript / Frontend Development
July 1, 2019 - September 30, 2019Node Development
April 1, 2021 - June 30, 2021JavaScript / Frontend Development
July 1, 2019 - September 30, 2019Node Development
April 1, 2021 - June 30, 2021JavaScript / Frontend Development
July 1, 2019 - September 30, 2019Node Development
April 1, 2021 - June 30, 2021JavaScript / Frontend Development
September 1, 2019 - September 30, 2019Node Development
February 1, 2021 - February 28, 2021Industry Experience
Software & Internet, Gaming, Professional Services, Media & Entertainment, Telecommunications, Computers & Electronics
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
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