15May
15 May 2025
Posted by Nicolas Bidaux
Cloud Maturity

Portfolio Advisor for AWS Transform, an automated way to accelerate .NET modernization: Segmentation Criteria

Migrating custom applications from .NET Framework to .NET Core is can deliver several benefits including: cost efficiency, higher performance, improved security and better maintainability. Due to its cross-platform compatibility, .NET Core applications can run on different operating systems, including Linux, providing greater flexibility and reducing infrastructure costs.

CAST and AWS partnered to facilitate this for large portfolios of applications using their unique capabilities as follows:

  1. CAST Highlight to automatically analyze custom application source code and make recommendations to guide discovery, migration and modernization programs.
  2. AWS Transform to accelerate large-scale transformation with generative AI agentic technology and cloud excellence.

This article describes the technical criteria used by CAST Highlight to segment a large portfolio of custom applications by identifying the suitability of .NET applications for automated conversion to .NET Core using AWS Transform.
How CAST Highlight’s Portfolio Advisor for AWS Transform works
In CAST Highlight, we have developed a flexible and robust Portfolio Advisor dashboard that automatically recommends application candidates and sequencing for migrating from .NET Framework to .NET Core.
9770
Together with the AWS Transform team and services partners like SoftServe, we applied the multi-dimensional insights from CAST Highlight’s to customize this advisor and segment applications into categories. Based on field experience, we defined six segments as follows:

  • Ideal candidates: .NET applications that meet all AWS Transform pre-requisites like .NET Framework version from 3.5 to 4.8, no web UI and less than 2 million lines of code with few OSS dependencies.
  • Good candidates: Same as the previous segment but with a web UI.
  • Fair candidates: .NET Core applications using a older version (up to .NET 7) and upgradable to a more recent version of .NET.
  • Complex candidates: applications requiring additional effort such as those with Legacy C# and more than 50 dependencies.
  • Not yet supported: C# applications with extra-large and massive codebases.
  • Not C# applications: The last segment contains all non-C# applications and C# applications using the latest versions where there is no need for upgrade.

9771
The segmentation criteria above can also be combined with other CAST Highlight insights to build a more comprehensive roadmap that takes into account Business Impact, Software Health, Open Source Safety and Containerization readiness. The latter can bring additional drivers for scalability and cost-efficiency when containers are orchestrated by AWS EKS.
For applications with numerous deprecated components, a “Rearchitect” or “Rebuild” approach should be considered if they are key for the business. For example, one approach would be to “Lift-and-Shift” to AWS as a first step and then modernize further using CAST Imaging to discover the detailed application mapping and plan refactoring steps for cloud native.
What’s next?
Not only does AWS Transform allow .NET applications to reduce their infrastructure costs but also reduce their modernization efforts. We are committed to our partnership with AWS and envisage extending support to include other technologies supported by AWS Transform like Java, Mainframe, and VMWare based applications.

So, stay tuned for more updates!

© CAST 2025