Роман

Fullstack .Net Developer (Backend-focused)
Kostiukov Roman
https://t.me/k057yl
[open contact info](look above in the "contact info" section)
github.com/k057yl
[open contact info](look above in the "contact info" section)
Skills:

C# (.NET Core/.NET 8), ASP.NET Core (Web API, MVC), Entity Framework Core, REST/gRPC, JWT Authentication,
SQL Server, PostgreSQL.
Blazor WebAssembly, Angular (RxJS, Components, Routing), Razor Pages/MVC, JavaScript/TypeScript,
HTML5/CSS3.
Clean Architecture, SOLID, OOP, Design Patterns, Microservices concepts, MVC/MVVM.
Git/GitHub, CI/CD (GitHub Actions), Azure/AWS Fundamentals, Docker (Basic), Jira, Confluence/Trello.
FluentValidation, Dynamic Localization, Custom Auth Providers, Interoperability (JS/C#), Query Optimization.

Languages:

UA: Native
RUS: Native
EN: Intermediate (B1)
Experience:
Freelance (Mar 2025 - Now)
Fullstack Developer
Full-cycle development of ASP.NET Core and Blazor WASM applications.
Building REST APIs, integrating external services, implementing Identity + JWT auth.
Client-server validation with FluentValidation, database design and optimization.
Development of Angular modules for admin panels and dashboards.
Dynamic localization systems and adaptive UI logic.

Nordbyte Solutions (Apr 2024 - Mar 2025)
.Net Developer
Development of internal and client systems based on ASP.NET Core.
Refactoring legacy .NET Framework modules to modern architecture.
Design and optimization of SQL Server queries.
Integration with external APIs and internal services.

Teknova Labs (Oct 2023 - Mar 2024)
Junior .Net Developer
Query optimization for SQL Server/PostgreSQL.
API integration tasks, bug fixing, feature extensions.

Projects:

Active development of personal and open-source projects:
https://k057yl.github.io/ClientKaraka/

About Me:
Passionately building reliable, maintainable systems based on Clean Architecture and SOLID principles. Focused
on delivering long-term business value through practical problem-solving, continuous improvement, and staying
ahead with modern .NET and front-end stacks. Proven ability to communicate technical solutions clearly and
directly.