Константин

Konstantin Huselnikov
Full-Stack .NET Developer
Email: [открыть контакты](см. выше в блоке «контактная информация») Telegram: @Kostas_Huselnikov
Phone / WhatsApp: [открыть контакты](см. выше в блоке «контактная информация») LinkedIn: [открыть контакты](см. выше в блоке «контактная информация»)

GitHub: github.com/KostasDevelope | Location: Ukraine (Ready for Remote / Relocation)

PROFESSIONAL SUMMARY
Result-oriented Senior Full-Stack Engineer with over 20 years of expertise in designing, developing, and
maintaining high-load enterprise systems, government-grade platforms, and cloud-native applications.
Exceptional proficiency across the entire .NET ecosystem (from legacy .NET Framework to modern .NET 9 and
ABP Framework) paired with extensive frontend experience (Blazor, Angular, Vue.js, Telerik Kendo UI). Proven
track record of handling asynchronous messaging (Kafka, RabbitMQ), optimizing database performance, and
implementing complex business workflows for international clients.

CORE SKILLS
• Backend & Architecture: C#, .NET Core 9, .NET Framework 4.8, ABP Framework, Web API, Microservices,
Distributed Systems, OOP/SOLID
• Messaging & Caching: Apache Kafka, RabbitMQ, Redis
• Frontend Development: Blazor WebAssembly (SPA), TypeScript, JavaScript, Angular, Vue.js, jQuery, Telerik
Kendo UI, Bootstrap
• Databases & ORM: MS SQL Server (T-SQL, Full-Text Search), Entity Framework Core, Code First
• Cloud, Desktop & Mobile: AWS (S3), .NET MAUI, Xamarin (XAML), WPF, Windows Forms, C/C++

PROFESSIONAL EXPERIENCE
VPW CARP (Social Project) | Full-Stack .NET Developer (Volunteer / Creator)
2025 – 2026
vpwcarp.kh.ua — A comprehensive Content Management System (CMS) and social platform tailored for a public non-
profit organization.
• Architected and implemented the entire platform from scratch using the modern ABP Framework and .NET
Core 9.
• Designed a responsive Single Page Application (SPA) frontend, delivering a seamless user experience.
• Integrated Redis for distributed caching to optimize page response times and minimize database hits.
• Built a secure data schema using MS SQL Server 2022, leveraging advanced query capabilities for global
search and data aggregation.
Technologies: C#, .NET Core 9, ABP Framework, MS SQL Server 2022, Redis.
Seyfor (Czech Republic / Remote) | Senior Full-Stack .NET Developer
2022 – 2026
Eldax — A proprietary, high-security enterprise information system developed for the Czech government, managing end-
to-end document accounting, electronic signatures, validation workflows, and auditing.
• Developed and maintained scalable backend microservices using C# and ASP.NET MVC (4.8) under strict
security protocols.
• Engineered reliable asynchronous communication paths between services by implementing Apache Kafka
and RabbitMQ, ensuring zero data loss during high-volume document processing.
• Designed rich, interactive, and high-performance user interfaces using Telerik Kendo UI, streamlining
complex validation workflows for government officials.
• Optimized heavy database interactions and data models via Entity Framework, significantly reducing query
latency and system resource consumption under peak loads.
Technologies: C#, ASP.NET MVC 4.8, Entity Framework, Apache Kafka, RabbitMQ, Telerik Kendo UI, MS SQL Server.

Triathlon Ireland (Ireland / Remote) | Full-Stack .NET Developer
2021 – 2022
Enterprise web system designed for recording, orchestrating, and management of national and international sports
competitions.
• Upgraded core system components to .NET Core 5, designing scalable Web APIs to serve dynamic web
clients.
• Developed responsive user modules using Vue.js, improving overall registration and navigation workflows
for athletes and coordinators.
• Integrated AWS cloud services, utilizing S3 buckets for secure storage, retrieval, and compliance
management of digital documentation.
• Maintained legacy Web Forms sections, ensuring backward compatibility and zero downtime during the
hybrid migration process.
Technologies: C#, ASP.NET Web Forms, .NET Core 5, Web API, Vue.js, MS SQL Server, AWS S3.

Technoserv ITL (Remote) | Full-Stack .NET Developer
2016 – 2021
Eldax — High-load documentation accounting, electronic signing, and verification platform.
• Implemented enterprise business logic patterns using C# and ASP.NET MVC 4.8, maintaining stability
across high-security environments.
• Integrated asynchronous messaging protocols via RabbitMQ and Apache Kafka to optimize communication
queues between background validation services.
• Managed database schemas and data migration strategies using Entity Framework and MS SQL Server,
enhancing query execution speeds.
Technologies: C#, ASP.NET MVC 4.8, Entity Framework, RabbitMQ, Apache Kafka, MS SQL Server.

United Bible Societies (Remote) | JavaScript / Mobile Developer
2015 – 2016
Cross-platform mobile application development for global content distribution and localized media interaction.
• Engineered fluid UI components and state logic using TypeScript and Angular.
• Leveraged React Native architecture to deploy cross-platform mobile apps, significantly reducing code-
sharing friction between iOS and Android platforms.
• Optimized client-side data synchronization algorithms to enable offline-first capabilities for users globally.
Technologies: TypeScript, Angular, React Native, JavaScript.

PNI Media (Remote) | Full-Stack .NET Developer
2012 – 2015
E-commerce platform specialized in highly customizable personalized print products (photo books, calendars, canvas
items).
• Developed complex front-end single-page editors using ExtJS 4, Ext.NET 2, and AngularJS, allowing precise
user manipulations of large image assets.
• Built robust server-side processing mechanics via ASP.NET MVC 4 and Entity Framework 4.0 to parse high-
resolution print layouts.
• Tuned MS SQL Server 2008 R2 database structures, indexing strategy, and stored procedures to handle
volatile transactional consumer traffic.
Technologies: ASP.NET MVC 4, Entity Framework 4.0, MS SQL Server 2008 R2, ExtJS 4, Ext.NET 2, AngularJS, jQuery,
Bootstrap.

Agiboo (Remote) | Full-Stack .NET Developer
2010 – 2012
Commodity Trade and Risk Management (CTRM) enterprise system providing sophisticated contract matching,
transactional history tracking, commodity risk analysis, and derivative modeling.
• Authored critical financial and transactional modules utilizing ASP.NET MVC 3 and the Razor view engine.
• Pioneered database development workflows using Code First Entity Framework 4.1, accelerating feature
delivery cycles.
• Constructed dynamic user analytical dashboards combining jQuery, AJAX, and rich data tables interacting
with MS SQL Server 2008 R2.
Technologies: C#, ASP.NET MVC 3, Razor, Entity Framework 4.1 (Code First), jQuery, MS SQL Server 2008 R2.

MovieCrow (Remote) | Full-Stack .NET Developer
2010
High-traffic media and informative portal focused on monitoring public sentiment, reviews, and tracking for the Indian
entertainment and music industry.
• Created scalable public content delivery pipelines using ASP.NET MVC 3 and Entity Framework.
• Implemented heavy client-side interactivity and asynchronous rating widgets using jQuery and AJAX.
• Optimized relational data views within MS SQL Server 2008 R2 to gracefully handle sudden multi-user
concurrent traffic spikes.
Technologies: ASP.NET MVC 3, Razor, Entity Framework, jQuery, MS SQL Server 2008 R2.

Ilyich Iron and Steel Works (Mariupol, Ukraine) | Software Engineer / C# Developer
2004 – 2011
Automation, heavy desktop systems, and lower-level manufacturing systems integration for one of the largest
metallurgical industrial enterprises in Europe.
• Engineered secure desktop applications for production control and metallurgical analytics utilizing
Windows Forms and WPF.
• Established service-to-service service layers across company sub-systems by developing Windows
Communication Foundation (WCF) configurations.
• Maintained and optimized critical low-level desktop applications and legacy libraries using C++ Builder and
C.
Technologies: C#, Windows Forms, WPF, WCF, C, C++ Builder.

EDUCATION
2001 - 2006 | Priazovsky State Technical University (PSTU), Mariupol
Qualification: IT Engineer / Specialist Degree

LANGUAGES
English: Intermediate | Ukrainian: Native