Experience

Maintain and grow large distributed systems for the financial sector while driving their step-by-step migration from a legacy stack to the modern web.

• Migrating systems from .NET Framework and WPF to .NET 10, Web API (REST), and CQRS, integrating the backend with an Angular front end (PrimeNG, Tailwind CSS).
• Implementing deferred and recurring background jobs with Quartz.NET — scheduled exports, reports, and data synchronisations.
• Maintaining, extending, and locally refactoring the existing WPF applications for code stability.
• Speeding up heavy PostgreSQL reports by hand-writing SQL (CTEs, window functions) instead of ORM queries and partitioning tables by period.
• Breaking down technical requests, keeping documentation (including compliance review), and writing Bash and Python scripts for routine work: data exports, log parsing, and config migrations.

• .NET 10
• .NET Framework
• Web API (REST)
• CQRS
• Quartz
• TypeScript
• Angular
• PrimeNG
• Tailwind CSS
• WPF
• Avalonia
• Python
• PostgreSQL
• MS SQL Server
• Entity Framework
• ADO.NET
• Docker
• Git

Built the server side of a microservice cinema ticketing platform.

• Designed microservices, implemented business logic (CQRS), and integrated services through RabbitMQ.
• Designed database schemas and optimised queries, organising storage across PostgreSQL, MongoDB, Redis, and object storage.
• Implemented authentication (JWT, OAuth 2.0) and real-time client–server interaction over SignalR.
• Built frontend components in React + TypeScript (TanStack Query / Router, Zustand, Tailwind CSS, shadcn/ui) and a mobile app in Flutter.
• Ran code reviews and demos, and wrote unit tests.

• .NET Core
• EF Core
• Clean Architecture
• Microservices
• CQRS
• SignalR
• Hangfire
• FluentValidation
• Mapster
• PostgreSQL
• MongoDB
• Redis
• RabbitMQ
• Nginx
• ELK
• React
• TypeScript
• TanStack Query
• TanStack Router
• Zustand
• Tailwind CSS
• shadcn/ui
• Docker
• Flutter
• xUnit
• Git

Built and maintained a pool of high-load fintech microservices integrating with cryptocurrency trading platforms.

• Wrote performant API clients for exchanges' REST and WebSocket APIs, honouring rate limiting.
• Introduced multithreading and async data pipelines, caching, and memory optimisation in PostgreSQL, keeping raw tick data and logs in ClickHouse.
• Designed microservices on Clean Architecture with CQRS, queue-based inter-service communication, background jobs (Quartz), and retry policies.
• Moved historical-data collection jobs from .NET (Quartz) to Apache Airflow and configured restart chains.
• Took part in containerisation (Docker), CI/CD pipelines, integration and unit test coverage (xUnit, Moq), and documentation.

• .NET Core
• EF Core
• CQRS
• Docker
• CI/CD
• Clean Architecture
• Microservices
• Message Brokers
• PostgreSQL
• Redis
• Quartz
• React
• TypeScript
• TanStack Query
• TanStack Router
• Zustand
• Tailwind CSS
• shadcn/ui
• xUnit
• Moq
• Python
• Apache Airflow
• Git

Developed and maintained the internal ERP system of a road-transport company: orders, finance, staff, accounting, and reference data.

• Built new screens and grids on Kendo UI (filters, grouping, aggregates, auto-sums) and the server endpoints behind them.
• Moved heavy operations from memory into the database: sorting by composite and hierarchical fields, aggregates, and projections instead of loading whole entities.
• Optimised NHibernate: removed N+1 queries, dropped eager collection materialisation, and profiled with NHibernate Profiler.
• Refactored legacy code: decomposed large methods and moved business logic from the front end to the server.
• Wrote SQL migrations, prepared seed scripts, and corrected inconsistent data in the database.

• ASP.NET Core
• Kendo UI
• NHibernate
• MariaDB
• MySQL
• AutoMapper
• Hangfire
• GitLab CI/CD
• NUnit
• FluentAssertions
• JavaScript