Костянтин

KOSTIANTYN MYRONIUK
.NET Backend Developer
Vinnytsia, Ukraine | [open contact info](look above in the "contact info" section) | [open contact info](look above in the "contact info" section)
LinkedIn: [open contact info](look above in the "contact info" section) | GitHub: github.com/KostiantynMyroniuk

PROFESSIONAL SUMMARY
.NET Backend Developer with freelance and project experience building REST APIs, modular monoliths and microservices on
.NET and ASP.NET Core. Applies Clean Architecture, feature-based design, SOLID and CQRS with MediatR; builds event-
driven systems with MassTransit, RabbitMQ and Azure Service Bus and service-to-service calls over gRPC. Works with Azure,
Docker and CI/CD, and backs code with unit and integration tests (xUnit, Moq, TestContainers).

TECHNICAL SKILLS
Languages: C#, SQL (T-SQL), LINQ
Frameworks: .NET 6-10, ASP.NET Core Web API, Entity Framework Core
Architecture & Patterns: Clean Architecture, Feature-based (Vertical Slice) Architecture, CQRS, MediatR, DDD, SOLID,
Microservices, Modular Monolith, Outbox, Inbox
API & Communication: REST API, API Versioning, OpenAPI/Swagger, gRPC, JWT Authentication
Messaging: MassTransit, RabbitMQ, Azure Service Bus
Databases & Caching: MS SQL Server, Redis
Cloud & DevOps: Microsoft Azure, Docker, Docker Compose, CI/CD, .NET Aspire, Git
Testing: xUnit, Moq, TestContainers
Tools: GitHub, GitHub Copilot, Antigravity

WORK EXPERIENCE
Freelance .NET Backend Developer | Remote | [02.2026 – 08.2026]
Tech stack: C#, .NET, ASP.NET Core, Entity Framework Core, MS SQL Server, MassTransit, RabbitMQ, Docker, xUnit, Moq,
TestContainers
• Designed and delivered REST APIs on ASP.NET Core and EF Core, organised by feature-based architecture so modules
stay isolated and easy to extend.
• Introduced API versioning, allowing breaking changes to ship without disrupting existing clients.
• Implemented asynchronous messaging between components with MassTransit and a message broker, decoupling
services.
• Covered business logic and endpoints with unit and integration tests (xUnit, Moq, TestContainers) to catch regressions
before release.
• Worked directly with clients to clarify requirements and deliver tasks end to end.

PROJECTS
Order Services — microservices order-processing demo | github.com/KostiantynMyroniuk/order-services
Tech stack: .NET 10, ASP.NET Core, MS SQL Server, Redis, RabbitMQ, gRPC, Docker, CI/CD, JWT Authentication
• Built a containerized order-processing microservice on ASP.NET Core and .NET 10, with Docker and a CI/CD pipeline for
automated deployment.
• Applied Domain-Driven Design and CQRS to separate command and query responsibilities, improving maintainability
and scalability.
• Used Redis for basket caching and idempotent request handling, preventing duplicate order processing.
• Connected services through RabbitMQ (asynchronous, event-driven) and gRPC (synchronous, high-performance).
• Secured API endpoints with JWT authentication.
Also on GitHub: JAT — AI-ready job application tracker (versioned REST API, MCP server, Vertical Slice Architecture,
TestContainers) | github.com/KostiantynMyroniuk/JAT

EDUCATION
Bachelor of Science in Software Engineering — Vinnytsia National Technical University, 2026
Relevant coursework: .NET basics, software architecture, algorithms.

LANGUAGES
Ukrainian — Native | English — B1 (Intermediate)