.NET backend
ASP.NET Core, EF Core, PostgreSQL
REST APIs, JWT, roles, transactions and business workflows
Junior C#/.NET Developer | Computer Engineering Student
Robert Tworek
I build business applications in C# and .NET, focusing on ASP.NET Core backends, relational PostgreSQL databases and clear user workflows. My projects combine domain logic, authorization, automated tests, Docker and React or Avalonia UI interfaces. I am looking for my first role where I can grow through production code, code review and teamwork.
At a glance
Projects
Featured projects
I focus on three C#/.NET and PostgreSQL projects. Each case explains the problem, key technical decisions, implemented scope and my specific contribution to the system.
ASP.NET Core + PostgreSQL
Order Flow Management System
areaorders and fulfilmentcore.NET 8 + PostgreSQLprocesspayment, inventory, shipmentquality45 tests + Docker
Problem / Goal
The main challenge was keeping the complete process consistent: order status, stock reservation, payment and shipment must remain aligned even when failures or concurrent requests occur. Lifecycle rules are controlled by the domain model, while inventory operations use PostgreSQL transactions and optimistic concurrency.
Key technical decisions
The order lifecycle is encapsulated in the domain model instead of being scattered across controllers. Stock reservation uses transactions and xmin-based concurrency, while events that require background processing are written to an Outbox in the same transaction as the business change. A separate Worker handles retries and moves a message to dead-letter after five failed attempts.
Key features
- order lifecycle from Draft and PendingPayment to Processing, Shipped and Completed, including cancellation and refund paths
- Customer, WarehouseEmployee, Manager and Administrator roles with policies controlling operations and data access
- transactional stock reservation with PostgreSQL optimistic concurrency preventing two customers from buying the last unit
- payments, shipments, status history, sales reports, low-stock reporting, audit logs and centralized ProblemDetails errors
- Outbox Worker with retry tracking, error logging and dead-letter handling
My contribution
- designed the domain model, relations and controlled order lifecycle
- implemented an ASP.NET Core Web API with JWT, roles, validation and ProblemDetails responses
- protected stock reservation with transactions and PostgreSQL optimistic concurrency
- created 45 automated tests, a Docker Compose environment and a GitHub Actions pipeline
Technical scope
ASP.NET Core 8C#EF Core 8PostgreSQL 16MediatRJWTDockerxUnitTestcontainers
45
tests
4
roles
Docker + CI
delivery
Project gallery
Selected project screens and results.
GitHub
Other projects on GitHub
Selected repositories that complement my main .NET focus, including web, algorithmic and academic projects. Each card links directly to the code and project documentation.
GitHub filter
TypeScript
bilingual portfolio website
Personal project: bilingual portfolio website built with Next.js, React, TypeScript and Tailwind CSS.
bilingualgithub-apinextjs
Repository
Python
vocabulary learning app
University project: a Django web application for learning vocabulary with word sets, flashcards, quizzes and progress tracking.
cssdjangoflashcards
Repository
C++
tsp algorithms benchmark
University project: comparing exact algorithms, heuristics and metaheuristics for TSP and ATSP using Python and C++.
algorithmsatspbranch-and-bound
Repository
Java
restaurant process simulation
University project: demonstrating multi-process communication, resource allocation and a live Swing GUI through a restaurant simulation.
javamulti-processoperating-systems
Repository
Technologies
Technologies and tools
I have used the following technologies in personal and team projects. My core direction is C#, ASP.NET Core, Entity Framework Core and PostgreSQL; the remaining tools support interfaces, testing, repeatable environments and technical documentation.
Core stack
APIs, business logic, authorization, transactions and data access
C#.NETASP.NET CoreEF CorePostgreSQLREST API
Frontend and desktop
operations panels, forms and cross-platform applications
ReactTypeScriptAvalonia UIMVVMNext.js
Testing and DevOps
multi-level testing, containerization and CI automation
xUnitTestcontainersPlaywrightDockerGitHub Actions
Technical background
academic projects, systems and networking, data analysis, documentation and repository work
Python/DjangoJavaC++SQLLinuxTCP/IPMicrosoft 365Excel
Education
Education and specialization
My technical education and engineering studies gave me broad foundations in programming, databases, computer systems, networking, testing and documentation. I apply those foundations to business applications built with .NET.
2022 - present
Wrocław University of Science and Technology
B.Eng. in Computer Engineering - in progress
Specialization: Information Systems in Medicine. The program covers programming, databases, information systems, networking, testing and technical and project documentation.
2018 - 2022
Electronic Schools Complex in Bolesławiec
IT Technician
The program covered computer systems, networking, peripheral devices, database fundamentals, website development and Microsoft 365. I completed my vocational work placement at St. Luke's Hospital in Bolesławiec.
Contact
Get in touch
I am looking for my first Junior C#/.NET Developer role or an internship with a path to further development. I am particularly interested in ASP.NET Core backends, full-stack applications and systems built on relational databases. I am open to opportunities in Wrocław, hybrid or remote.
Robert Tworek - 2026
Next.js / React / TypeScript / Tailwind CSS / Motion