.NET & C# engineering · Hungary
Systems that outlive their rewrite.
operandor is a software development company led by Andor Sípos. We take systems that already carry a business and make them maintainable again — then keep building on them.
Commercial .NET
13 yrs
5 in lead / architect roles
Client base
HU + EU
Enterprise and mid-market
Engagement start
2 wks
Fixed-scope discovery
Architecture assessment: 18 projects, 4 integrations, 1 database nobody documented. A plan you can ship against. The full software development lifecycle: discovery, planning, specifications, architecture, implementation, review, testing, release, operations and evolution or retirement. AI-assisted specification-driven development (ASDD) supports our .NET engineering expertise with specification-guided AI assistance, human review and accountable decisions.
What we do
Five things, done properly
Legacy-to-modern re-architecture
Aging systems become maintainable, cloud-ready platforms — in increments, without freezing the business.
Custom business applications
ERP, stock management, quote-to-service workflows, public-sector platforms.
Backend systems & integration
REST APIs, Azure Service Bus topologies, third-party integrations that stay observable.
BI & reporting
KPI dashboards and reporting built on the data the business already has.
eCommerce
nopCommerce plugin development and customisation.
Not sure which one you need?
Start with a two-week assessment. Fixed fee, written deliverable.
How we work
No rewrite-and-pray. Modernisation happens in increments, with the business running the whole time.
01
Assess
Two weeks. Read the code, map the integrations, write it down.
02
Stabilise
Tests and observability before features. Always.
03
Re-architect
Module by module, behind a facade, both systems live.
04
Hand over
Documentation and a team that can keep going without us.
Selected work
Case study
ERP replatform
Manufacturing · Hungary
A 14-year-old WinForms ERP moved to ASP.NET Core module by module, with both systems live for seven months.
.NET 8Azure SQLService Bus
Case study
Quote-to-service workflow
Field services · EU
One workflow replacing four spreadsheets and an inbox. Quote, schedule, serve, invoice.
BlazorEF CoreSignalR
Case study
Public-sector reporting
Government · Hungary
A reporting platform with an audit trail that stands up to an actual audit.
ASP.NET CorePower BI
The stack
Boring technology, used well
Thirteen years in one ecosystem means the interesting decisions get spent on your domain, not on the framework.
C#.NET 8ASP.NET CoreBlazorEF CoreAzure Service BusAzure FunctionsAzure SQLSQL ServerDapperSignalRxUnitPower BInopCommerceDockerGitHub Actions