Hi @John Earle ,
The dotnet/Sign project now has a pre-release version with Trusted Signing integration to expand our support to NuGet. https://www.nuget.org/packages/sign/0.9.1-beta.24325.5
Once this is more stable, we will publish more information on how to use it with Trusted Signing, but I'm also checking internally to see if there is additional documentation I can share with you.
There was a similar request in Github recently that has an ongoing discussion on this topic. https://github.com/dotnet/sign/issues/683
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