Moderne Expands Agent Tools Platform with C# Support for Deterministic .NET Transformation

C# joins Java, JavaScript/TypeScript, Python, and more in the Lossless Semantic Tree (LST), enabling automated code quality remediation and .NET migration across enterprise codebases.

MIAMI--(BUSINESS WIRE)--Moderne, the Agent Tools company for AI-driven software engineering, today announced C# language support across its platform, extending deterministic, large-scale code transformation to .NET codebases. With this addition, engineering teams and coding agents can now apply the same governed, recipe-driven automation used for Java, JavaScript/TypeScript, and Python to C# systems, reducing manual effort, improving code quality, and accelerating .NET modernization.

The release comes as .NET teams prepare for a significant modernization cycle: both .NET 8 and .NET 9 reach end-of-support in November 2026, creating demand for automated tooling that can operate across large repository estates. While .NET remains foundational across industries such as financial services, healthcare, and government, teams have lacked safe, automated ways to execute changes consistently at scale. C# support closes that gap, bringing .NET into the same execution model already used across Moderne’s multi-language platform.

“Migrating hundreds of .NET repositories to .NET 10 would have cost us hundreds of engineering hours. With Moderne, we did it at a scale and speed that simply wouldn’t have been possible otherwise. Moderne delivered exactly what we needed to move fast without sacrificing code quality or engineering rigor.” — David Thoma, Head of Engineering, Billtrust.

C# is now supported within the Moderne Lossless Semantic Tree (LST), a compiler-accurate structural model that enables deterministic transformations across repositories. The LST represents code at a semantic level while preserving formatting and structure, allowing automated changes to be applied safely across hundreds of repositories without manual intervention. Recipes can analyze symbol usage, detect code quality issues, and execute coordinated transformations across entire systems. Because the LST uses a shared data model, building-block recipes like Change Method Name, Find Method Usages, and Change Type work identically across all supported languages.

The initial release includes over 700 recipes across two primary categories. A code quality library provides more than 420 recipes modeled after Roslynator, now able to run across entire repository estates at enterprise scale, enabling teams to systematically detect and remediate style violations, correctness issues, and common anti-patterns. A migration library delivers automated upgrade paths for .NET runtime transitions, with coverage spanning .NET Core 1.0 through .NET 10. Organizations can extend this library with custom recipes written in C# or assembled from declarative YAML building blocks shared across all supported languages.

“Coding agents are transforming how teams write and maintain software, and the teams seeing the biggest gains are the ones that pair agent speed with deterministic infrastructure,” said Jonathan Schneider, CEO and co-founder of Moderne. “Adding C# to the Lossless Semantic Tree means .NET teams get the same governed, large-scale automation our Java customers have relied on across thousands of repositories.”

"Moderne's expansion into C# extends their automated, scalable approach to code modernization to one of the largest enterprise developer communities in the world," said ShiSh Shridhar, Global Director Retail & CPG Startups, Microsoft. "We're pleased to continue supporting Moderne as they help organizations reduce the cost and complexity of maintaining and securing their .NET applications."

C# recipes are distributed as NuGet packages and are available immediately through the Moderne Platform via the existing workflows and governance controls. Engineering teams can run code quality analysis, execute migration recipes, and manage dependencies, including NuGet package upgrades and .csproj dependency updates, using the same infrastructure already in place for other supported languages. For technical details, see https://moderne.ai/blog/moderne-csharp-dotnet-support.

About Moderne

Moderne is the Agent Tools company that provides deterministic, governed infrastructure for AI coding agents operating across enterprise software systems. Moderne helps organizations scale AI-driven engineering with organization-wide intelligence and governed execution, continuously improving software quality while maximizing the value of their AI investments. Based in Miami, Moderne investors include Acrew Capital, Intel Capital, True Ventures, Mango Capital, Allstate Strategic Ventures, Morgan Stanley Ventures, Amex Ventures, and TIAA Ventures. To learn more, visit www.moderne.ai.