Automapper, MediatR and MassTransit Move to Paid Licenses

The .NET and C# ecosystem in the open source community is collapsing.

This is a post I originally didn’t plan to write, but just a few hours ago, in light of the latest news, I feel compelled to share it with all of you here for .NET or C#. 

1 - MediatR, AutoMapper and MassTransit change their licenses

The first thing we need to look at is where this problem started. Yesterday, April 2, we witnessed three of the most popular libraries within the C# ecosystem change their licenses from fully open source to requiring a commercial license. 

First came AutoMapper and MediatR, both maintained by the same person. Here’s the blog explaining the reasons: https://www.jimmybogard.com/automapper-and-mediatr-going-commercial/ 

Later that same day, we learned that the next version of MassTransit (v9) will also require a commercial license; the explanation is here: https://masstransit.io/introduction/v9-announcement.

The reasons are simple, as I already mentioned in the post about Open Source, where we mostly talked about mock, which last August 2023 made some updates to try monetizing. The people maintaining MediatR, AutoMapper and MassTransit are tired of maintaining them for free and want to earn something from their work. 

As I said in that post, maintaining projects takes a lot of time and is not profitable. Meanwhile, everyone wants updates and new features instantly. And that’s just not realistic. 

Out of curiosity, although he mentioned it as just an anecdote, Jimmy Bogard, the creator of Mediator and AutoMapper, said this on Reddit two months ago: 

Obviously, he has since changed his mind, but the use of the word "never" is interesting. 

As I always say, I think it’s fair that everyone can do as they wish with the licenses of their open source packages.

2 - The failure of the .NET Foundation

This is where the .NET Foundation comes in. For those who don’t know what I’m talking about, the .NET Foundation is a Microsoft-backed community that supports development and collaboration within the .NET world. The idea is to ensure the long-term sustainability of open source software development within .NET. 

Obviously, this hasn’t worked. In the last 18-24 months we’ve seen many popular .NET libraries shift to a paid model. This includes IdentityServer for example, but also ImageSharp, FluentAssertions, QuestPDF, Mock and, as of yesterday, MediatR, AutoMapper and MassTransit. These are libraries heavily used in almost every enterprise project. Those are the ones for now, but if these changes work out, who knows which libraries will be next. 

In my opinion, everything happening now points directly at the .NET Foundation and Microsoft, who clearly don’t provide the support these open source packages need. What they should be doing is creating a rewards system or even offering a salary, but if all the support libraries get is showcasing their projects in a mini-conference within NetConf and a premium subscription for the .NET User group meetUp (which Microsoft owns), obviously it’s not worth it. What would be worth it is financial compensation. 

Many people will tell me that it’s open source and so on, but the reality is that the main users of these packages are companies, large companies that pay for Windows licenses, pay for Visual Studio licenses, and many who host everything in Azure. For this reason, it would make total sense for Microsoft to allocate an annual fund for distributing to all libraries in the .NET Foundation, since thanks to these libraries people use .NET.