Dot NET Application Migration

Many companies sooner or later face a point when their legacy applications, written on earlier versions of the .NET Framework, no longer meet business objectives. They become difficult to maintain, slow to run, poorly protected, and virtually impossible to integrate with modern solutions. With rapidly evolving technologies, these legacy applications are beginning to stifle growth and development.

Transitioning to .NET Core or ASP.NET Core isn’t merely a technology upgrade; it’s an opportunity to leverage modern technologies, streamline performance, and infuse new life into existing products.

Companies are getting cross-platform, easy improvements to scalability, better interoperability with modern tools and technology stacks, as well as being able to deploy applications to the cloud without unnecessary constraints, all by migrating to the core.

In this article, we will explain in detail why a business may need web application migration, how the migration process works, what migration services are available, and what best practices should be relied on to make the transition a step forward rather than a stressful one.

What is .NET Application Migration?

.NET application migration is the process of moving an application from one version of the .NET platform or runtime environment to another, most often from the legacy .NET framework to the more modern .NET Core or ASP.NET Core. Such core migration can concern both web applications and desktop solutions or server components.

Migration primarily serves the purpose of technology compatibility and performance improvement. With migration to .NET Core, you can increase performance, improve security, reduce support complexity, and accelerate release cycles.

The transition to a more modern architecture has made it much easier to connect cloud services and external APIs — what used to take weeks can now be realized much faster and with less effort.

Most importantly, everything that users love about your product doesn’t disappear. But there is freedom: you can quickly adjust to new trends, add a feature that customers are waiting for, or scale without headaches. And most importantly, you don’t have to throw out old code and start from scratch, as if the previous years of work were a draft in the trash.

Reasons to Migrate Your Legacy .NET Applications

Many companies are still using .NET applications written 5, 10, or even more years ago. These solutions worked great once upon a time — and, on the face of it, continue to get the job done. But have you ever wondered at what cost?

According to Deloitte, 82% of companies have failed to implement cost reduction strategies, and one of the key reasons they cite is outdated IT infrastructure and technology.

Business Wire research shows that 74% of organizations start modernization projects but fail to complete them. Most often this is due to the fact that existing systems are too complex to quickly adapt to current business tasks.

Below are the main reasons why migrating your application from legacy .NET versions is becoming increasingly important:

Obsolete Technologies and Libraries

Components used in the development of legacy .NET applications are often no longer supported or are discontinued altogether. This slows down teams, makes support difficult, and prevents the introduction of new features. As a result, the business loses flexibility and competitiveness.

Lack of Support for Older Versions of the .NET Framework

Microsoft has already discontinued active support for many versions of the .NET Framework, and this process is still in progress. This means a lack of updates, bug fixes, and compatibility with modern development tools. In the long run, such systems become increasingly vulnerable and expensive to maintain.

Increased Security Risks

Without regular updates, vulnerabilities remain unpatched. This makes legacy applications a target for attacks. In an era where privacy and compliance are becoming critical, legacy architecture becomes a potential source of serious reputational and financial loss.

Limited Scalability and Integration

Legacy architectures were designed with a monolithic approach and on-premises infrastructure in mind. In today’s environment, where reliance is placed on cloud solutions, microservices, and API-centric integration, such systems become a bottleneck. This is why many companies, even after starting digital transformation, cannot realize it in full — old applications are simply not adapted to the new realities.

Key Framework and Web API Challenges in Legacy Systems

Supporting legacy applications requires more and more resources, while the efficiency of such solutions decreases every year. Below is an overview of the key challenges companies face when working with legacy systems:

Challenges of Legacy Systems

The .NET Migration Process Explained

Legacy system migration is not just porting code from one platform to another. It is a full-fledged migration strategy where it is important to preserve stability, improve performance, and create a foundation for development. Here is how it happens in practice, step by step.

Analyzing and Auditing The Current Solution

It all starts with an audit. The team audits the current application: examining its application architecture, code base, integrations, dependencies, and problem areas. At this stage, it’s important to understand what really needs to be migrated and what can be simplified or even removed. Technical debt, risks, and the team’s readiness for change are also analyzed.

Architecture Planning

After the analysis, a new technical basis for the project is formed. It can be a partial redesign of the architecture, transition to microservices, or adaptation to cloud technologies. The main goal is to lay a solid foundation on which the application will not only work but also scale. It is also determined what technologies, libraries, and infrastructure will be used in the new version.

Logic Transfer, API, UI

At this stage, the most noticeable part of the work begins — the migration of the “content” of the application itself. Everything that makes the system useful: business logic, interfaces, ways of interaction with other services — is carefully transferred to the new environment. Sometimes the appearance (UI) can be left almost unchanged, especially if it already suits the users.

But sometimes it happens the other way around: the UI has to be updated or even created from scratch if the approach or design of the platform itself changes. The main thing here is not to lose the important things. All the key functions that users are accustomed to and on which the business is based should remain and work better.

Testing and Debugging

After the application migration, thorough testing is performed: first functional, then load, and integration testing. Bugs are identified, stability is checked, and incompatibilities are eliminated. It is important to make sure that everything works as well — or better — than in the old version. This stage is critical for user and business confidence: the application must remain reliable.

Support

When a new solution is launched, the team collects feedback, capturing what worked and what could be improved. This stage helps to improve the quality of future migrations and development processes in general. The maintenance stage also begins: monitoring, technical support, and gradual optimization for real operating conditions.

How SCAND Helps Migrate and Modernize .NET Applications

At SCAND, we’ve been developing and upgrading .NET applications for clients in industries ranging from fintech and logistics to healthcare and gaming for over 20 years. Today, when many companies are faced with the need to migrate to .NET Core or newer versions of .NET, we help make it as reliable, secure, and future-proof as possible.

Our Experience in Dot NET Core Migration and Web Application Modernization

We participated in migration projects that required not just rewriting code but a complete overhaul of the architecture, improving performance, ensuring stable operation in the cloud, and preserving business logic without losses. This includes applications with dozens of interconnected modules, complex APIs, and unique interfaces.

SCAND knows how to adapt to the specifics of each project: whether it’s a smooth transition in several phases or a complete migration with redesign and new functionality (such as moving to Blazor or integrating with cloud platforms).

Audit and planning approach

Before starting work, we conduct a technical audit: we study the code structure, dependencies, current constraints, and business goals.

Together with the customer, we determine which components require complete redesign, what can be retained, and what can be replaced. This helps to reduce time, reduce risks, and accurately estimate the scope of work.

At the planning stage, we create a clear project roadmap: from compatibility assessment and timeline calculation to the selection of suitable technologies and team training. This approach makes the entire process transparent and manageable for the client.

How We Solve Compatibility and API Challenges

Compatibility with old libraries and APIs is one of the most frequent and challenging issues in migration. We take care of it: we develop adapters, update obsolete data exchange protocols, and thoroughly test all integrations. If necessary, we help to rebuild the architecture so that it meets modern requirements for security, speed, and scalability.

We also completely take care of all the work needed to connect any external APIs and all cloud services, etc. If before everything was unwieldy or you had to find workarounds, you can now forget about it after migration. Everything will work as planned. It will be reliable, clear, and painless. You will finally be able to use modern tools with the reassurance that nothing will break or take away from your usual way of doing things.

Why Clients Choose SCAND

Companies choose SCAND for our practical experience, systematic approach, and transparency. We speak to our clients in a clear language, do not overload them with technical details, but have a deep understanding of technology and business goals.

We offer not just “application migration” but a solution that works, meets market requirements, and opens the way to development. For our .NET engineers, it is important not only the result but also that the customer feels confident at every stage of the project.

Conclusion

Migrating .NET applications is not just a technical upgrade, but an important strategic move. Outdated solutions limit flexibility, increase support costs, and hinder business growth. Migrating to a modern platform can reduce costs, accelerate product development, and ensure future competitiveness.

If your application is becoming difficult to maintain, scales poorly, or doesn’t integrate with new services -— this is a serious signal that it’s time to think about modernization. The earlier you start the transition, the fewer risks and costs you will incur in the future.

The SCAND team is ready to help you through this journey: from the first audit to the complete migration and support of the already updated solution. We work transparently, with a focus on business objectives, and always offer the best scenario for your task.

Ready to discuss a project? Contact us and we’ll tell you the best way to modernize your .NET application.