What you can build with .NET
.NET is a versatile platform. With a single language, C#, and the same libraries, you can build:
- backends for websites, portals and mobile apps;
- enterprise systems for managing requests, documents, inventory or manufacturing;
- background services that sync data with accounting software or banks every night;
- Windows desktop applications used by office staff;
- games and interactive applications on Unity.
Businesses most often need the first three: systems with lots of business logic, integrations and users with different permissions.
C# and .NET advantages
- A strict, expressive language. C# catches many errors before the code even runs, and modern language features keep code concise and readable.
- High performance. Modern .NET is fast and uses server resources efficiently, which shows under heavy load.
- Native Microsoft integration. Sign-in with corporate accounts, Azure, Microsoft 365, Excel reports: all of it connects with standard tools.
- Great tooling. .NET development and debugging environments are among the best available, which speeds up bug fixing.
- Predictable releases. Microsoft ships new versions on a clear schedule and announces in advance how long each one will be supported.
Limitations to be aware of
- The .NET Framework legacy. Many systems are written on the old Windows-only platform. They can be moved to modern .NET, but some technologies will have to be replaced.
- Licensing for related products. .NET itself is free, but if the project uses a paid Microsoft database or server OS, those costs need to be budgeted.
- Fewer off-the-shelf solutions for standard websites. For a content site or online store, PHP has far more ready-made platforms and modules, so the same project on .NET often costs more.
- Regular upgrades. Standard-support versions have a short lifespan, so the project needs planned upgrades to newer versions.
When to choose something else
If your company isn't tied to Microsoft products and the system is large and long-lived, Java is an equally strong alternative; the choice often comes down to your existing team and infrastructure. For a small website that needs to launch quickly and be easy to hand off for maintenance, PHP and off-the-shelf CMS platforms are more practical.
.NET Framework vs. modern .NET: what's the difference
This is the question we hear most often. Originally there was only .NET Framework, a Windows platform. It still works and receives security fixes, but no new features are being added.
Modern .NET (formerly .NET Core) is cross-platform, open source and much faster. This is the platform to move to. Migration is straightforward if the project uses standard libraries, and harder if it relies on Web Forms or other technologies that don't exist on the new platform. We first assess what can be migrated automatically and what has to be rewritten, then move the system over in stages. Our general approach to these projects is described on the legacy system modernization page.
Web, CMS and cloud
There are several paths for .NET web projects. For content-heavy sites edited by marketers, we use Umbraco, a .NET-based CMS. For services, customer portals and APIs, we use ASP.NET Core.
.NET applications work well on Azure: databases, message queues, file storage and event-driven functions. If your infrastructure is on Microsoft's cloud, we'll configure that too; learn more on our cloud infrastructure and Azure page.
Windows applications for employees
Many companies still run C# desktop applications: point-of-sale systems, warehouse apps, operator workstations, label-printing utilities. Often they were written years ago by a single developer, and now nobody dares to touch them.
We help with these applications in two ways. We can improve and stabilize the existing app: upgrade the platform, fix bugs, add data sync with a new accounting system. Or we can gradually move its features to a web interface that opens on any computer with no installation. Which option pays off depends on how tightly the app is tied to hardware and local files.
Integrations and background processes
Enterprise .NET systems typically exchange data with ERP and accounting systems such as QuickBooks, CRMs, banks and websites. We move these data exchanges into separate background services with retries and logging: if an external system is unavailable, data isn't lost but sent later, and you can see what happened.
What affects cost
- Type of work: a new system, enhancements or migration from legacy .NET Framework.
- Amount of business logic: roles, workflows, documents, calculations.
- Integrations: accounting systems, banks, Microsoft products, external APIs.
- Infrastructure: Windows or Linux, on-premises servers or Azure, fault-tolerance requirements.
- Code condition: tests, documentation, the number of outdated technologies.
We provide an estimate after an audit or a discussion of your requirements and break it into phases so you understand what the budget covers.
FAQ
Do we need a Windows server? No. Modern .NET runs on Linux and in Docker containers, which is often cheaper to maintain.
Our system runs on .NET Framework. Can we leave it as is? For a while, yes; it still gets security updates. But new libraries are rarely released for it, so if you plan to keep developing the system, it's better to plan a migration.
Can .NET be combined with a React or Angular frontend? Yes, it's a common setup: .NET handles data and logic, and the interface is built separately.
Can a .NET system be moved to another data center or cloud? Yes. After migrating to modern .NET, the application is packaged in a container and runs wherever you prefer, without being locked into a specific host.
Is C# a good choice for mobile apps? Technically yes, but for mobile projects we more often recommend native development or Flutter, which have more ready-made solutions.
Why Promodex
We're upfront about when .NET is the right choice and when a task is easier to solve with other tools. Promodex has been in business since 2015, with 750+ projects in our portfolio. Our developers, designers and marketers are in-house, so accountability for results isn't spread across subcontractors. We show you the scope and phases up front, and after launch we support the system and upgrade it to new platform versions.
