9+ yearsBackend engineering
Building maintainable systems in C# and .NET.
.NET Backend Engineer
DenisŠijanov
I design and build software that is easy to understand, maintain, and evolve.
I have 9+ years of experience building backend systems in C# and .NET. My interests include software architecture, automation, and AI-assisted software development.
Tech stack.NETC#SQL ServerEntity FrameworkWPF / MVVMFeature flags
Production systemsC#, .NET, SQL
Billing, finance workflows, and operational business logic.
ArchitectureMaintainable systems
Systems built to keep evolving safely.
Currently buildingAI Factory & Lif-align
Autonomous engineering & AI-assisted productivity.
Experience
- MMewsBilling & Finance backend
Business-critical billing, taxes, and finance systems in a large C#/.NET platform.
- UUnicode SystemsHead Office / Back Office
Operational business systems — backend business logic, APIs, and database work in C#/.NET and SQL Server.
- GGOPASStoryBoard (WPF / MVVM)
Desktop application for building interactive software tutorials and training lessons.
- AAtosFirst professional role
Team-based development inside an existing enterprise C#/.NET codebase.
Currently working on
- AI FactoryActive project
An autonomous software development platform for planning tasks, running coding agents, and creating pull requests.
- Lif-alignActive project
A personal planning and reflection application connecting daily plans, tasks, habits, and journaling.
- Staff engineering and API designCurrently exploring
Studying wider technical influence and how backend APIs work as stable, understandable contracts.
Featured projects
All projectsActive
AI Factory
An experimental system where AI agents help move a real repository forward: selecting tasks, implementing changes, opening pull requests, and feeding lessons from each run back into the process.
Active
Lif-align
A personal beta application for planning the day, capturing reality, and reflecting on where time and energy actually go.
Mews / Billing & Finance
Historical correctness of accounting categories
How we stopped calculating the accounting category from the current configuration and started storing it so historical reports would stay stable.
Mews / Billing & Finance
Separating the Billing domain inside a monolith
A proposal for gradually clarifying Billing boundaries inside an existing monolith.
Mews / Billing & Finance
Feature Flag Runner
How I turned a feature flag into more than a boolean switch: a tool for rollout, logging, measurement, and result comparison.
GOPAS
StoryBoard
An internal WPF/MVVM application that captured screens and UI elements from other programs and turned them into interactive software tutorials.
Let's build something great together
I'm open to interesting problems and long-term collaboration. Feel free to reach out.