NuGet Package Alternatives

Last Updated: 2025-04-22

As part of ongoing efforts to reduce dependency risks and licensing surprises in our codebases, here’s a quick review of popular testing libraries and recent developments, along with recommended alternatives where relevant.

Package Function Recent Major
Issue		 Issue
Resolved?		 Alternative
#1		 Alternative
#2
Moq
799.7M downloads		 Mocking library See details ✅ Yes NSubstitute
168.2M downloads		 FakeItEasy
53.7M downloads
FluentAssertions
494M downloads		 Readable test assertions See details ❌ No Shouldly
66.4M downloads		 Use built-in Xunit.Assert methods
Automapper
660.5M downloads		 Object-object mapping See details ❌ No Mapster
38.9M downloads		 Write mapping logic natively
MediatR
244.8M downloads		 In-process messaging (CQRS) See details ❌ No Multiple new
alternatives		 Wait until commercial
license is required
Bogus Fake test data generator No known issues - – –
coverlet Code coverage tool No known issues - – –
FluentResults Result pattern for C# No known issues - – –
xUnit Testing framework No known issues - – –

Issue Details

Moq

  • Date: August 2023
  • Issue: Moq version 4.20.0 introduced SponsorLink, a closed-source dependency that extracts the developer’s email from the local Git configuration, hashed it, and transmitted it to a remote server.
  • Resolution: Moq version 4.20.2 removed SponsorLink from the package. However, the maintainer has expressed an intention to reintroduce SponsorLink in a future version.
  • Recommended Action: Upgrade Moq to version 4.20.2 or later for existing projects. Switch to using NSubstitute for new projects.

FluentAssertions

  • Date: January 2025
  • Issue: FluentAssertions version 8.0 introduced a commercial licensing model, requiring companies to obtain a paid license per developer per year for usage in commercial products.
  • Resolution: Version 8+ is free for open source and non-commercial use. Version 7 will remain fully open-source indefinitely and receive bugfixes.
  • Recommended Action: Keep FluentAssertions to version 7.x for commercial use.

Automapper & MediatR

  • Date: April 2025
  • Issue: Maintainers have expressed desire to have commercial licenses for both Automapper & MediatR. The nugets will remain free for open source and non-commercial use.
  • Resolution: Seek alternatives or wait until the the commercial license have been implemented.
  • Recommended Action: Continue using MediatR for now. Map objects natively rather than use Automapper.