A new resource from Microsoft named the .NET App Migration Toolkit focuses on streamlining the transition of older apps into modern forms. By addressing the need to move legacy apps to the cloud and using emerging technologies like .NET 8 and .NET 9 this toolkit offers helpful guidance.
Table of contents
Understanding the Need for .NET Modernization
We first saw the .NET Framework in 2002. Over the years Microsoft has enhanced the framework and rolled out new implementations including .NET Core and .NET 5-9 made for cloud and container uses. A significant number of operational applications utilize the initial .NET Framework.
Avoiding Tech Stagnation
Apps built with legacy .NET technologies can use versions that have been phased out. Adopting old technology can restrict lockable access to security updates and performance upgrades. Failing to update leads organizations to larger amounts of technical debt that complicates the upkeep of applications.
Realizing Cloud Benefits
Moving .NET applications to newer platforms reveals essential cloud benefits along with DevOps and application innovations. This support allows applications to move more easily and to align well with microservices. Quicker build times enhance functionalities for CD pipelines. Utilizing modern features, including machine learning, preserves the effectiveness of applications going forward.
Overcoming Migration Barriers
However, updating runtimes and frameworks is rarely trivial. Code breaks, dependencies shift, and teams battle testing and debugging issues. These modernization difficulties have slowed .NET re-platforming efforts. The .NET Migration Toolkit looks to change that dynamic.
Introducing the .NET App Migration Toolkit
Announced at Microsoft Build 2022, the .NET App Migration Toolkit is an open-source solution designed to simplify moving .NET Framework apps to .NET 5 and above. Let’s examine the core capabilities this offering offers.
Automated Code Analysis
The toolkit scans an existing .NET Framework codebase to uncover compatibility issues that could impede migration. It pinpoints any reliance on deprecated APIs, spotlighting areas that will require code changes. Teams gain objective insights into the level of effort needed upfront.
Suggested Path Forward
The analysis goes beyond surfacing breaking changes to recommend specific steps for moving the application forward. The guidance outlines code fixes, configuration changes, and dependency updates required before recompiling on .NET 5+.
Portability Validation
As developers implement suggested changes, they can run the toolkit again to validate whether the application meets the .NET Portability requirements for the target platform. Confirming that code now compiles on .NET 5+ with no errors gives teams confidence to proceed.
Migration Testing
The toolkit also assists with testing to ensure application behavior and outputs match the original .NET Framework app after migration. Identifying differences in the early stages prevents unexpected surprises down the road.
Key Migration Considerations
While the .NET App Migration Toolkit simplifies parts of the modernization process, teams still need to weigh several factors when planning an upgrade project.
Code Architecture Patterns
Monolithic apps with tightly coupled components will prove more challenging to migrate than modular microservices-based applications. More code refactoring is likely needed in monoliths to embrace cloud-native designs before lifting and shifting.
Third-Party Dependencies
If existing .NET Framework apps rely on outdated third-party libraries, those external dependencies will also require upgrading or replacing to work with modern target platforms. Checking for compatibility issues upfront is advised.
Access to Source Code
The toolkit analyzes code statically, requiring source file access. For ISV applications shielding code from access, developers may seek extra approaches to discover any flaws.
Test Coverage
How teams shift apps with minimal defects rests on the existing test coverage. Emphasizing the execution of automated business logic and UI workflows is necessary to identify regressions.
Team Skills
Skill in elegant .NET frameworks can quicken the process of migrating applications. Enhancing the skills of teams in parallel technologies like containers and Kubernetes will optimize the process of shifting apps to the cloud.
When to Use the .NET Migration Toolkit
The .NET App Migration Toolkit is particularly useful for enterprise teams maintaining business-critical, legacy LOB applications written in older .NET Framework versions. Upgrading these apps delivers real productivity and innovation advantages but can stir resistance without automated assistance.
Legacy Web Forms Apps
Web Forms ruled the web development roost for .NET developers in the early 2000s. While Microsoft ended support for this framework years ago, plenty of sites still run on aging Web Forms code. Migrating UI layers to Blazor or Razor Pages is now markedly easier.
Desktop and Mobile XAML Apps
The same holds true for desktop and mobile applications built with XAML frontends relying on deprecated parts of the .NET Framework like Windows Presentation Foundation (WPF) and Windows Communication Foundation (WCF). Here again, migration aids can smooth technology transitions.
On-Premises Line of Business Apps
Finally, the toolkit facilitates lifting and shifting critical internal business systems, such as ERP and CRM solutions, that are still confined to legacy on-prem hardware. Cloud modernization unlocks scalability and resilience for these apps.
How the Toolkit Works
Now that we’ve covered what the .NET App Migration Toolkit delivers and where it brings unique value, let’s briefly outline how it works under the hood.
Scanning Bytecode
The toolkit first compiles a .NET Framework application into platform-agnostic Common Intermediate Language (CIL) bytecode. This provides a universal snapshot of the app codebase for analysis.
Detecting Issues
Proprietary Roslyn analyzers then scan the CIL byte code looking for any use of now obsolete .NET Framework APIs or conventions incompatible with .NET 5+ platforms. All problem areas get flagged.
Processing Results
The toolkit processes results to supply developers with prescriptive next steps for addressing each raised concern through code changes. Guidance links out to relevant documentation on required fixes.
Confirming Readiness
After remediating noted issues, teams can perform another toolkit scan to confirm all blocking migration problems are resolved. If no further errors surface, the app should now compile on modern .NET versions.
Conclusion
The .NET App Migration Toolkit represents a breakthrough in assisting enterprise developers mired in legacy code finally make the leap to modern platforms. By automating parts of the discovery and remediation process, this toolkit saves valuable resources. As Microsoft continues enhancing support, the solution will become even more capable.
For .NET teams weighed down by technical debt, the time is now to start mapping out an application modernization strategy. Reach out to explore how the .NET Migration Toolkit can accelerate your cloud migration and innovation initiatives today!
