.NET buildpacks now support SLNX files

Change effective on 21 October 2025

We’ve updated our .NET buildpacks to support *.slnx (SLNX) solution files. If your app includes a *.slnx, *.sln, *.csproj, *.vbproj, or *.fsproj file in the root directory, Heroku automatically recognizes it as a .NET app.

Refer to .NET Behavior in Heroku for more details.