So lots of posts over the last few days about that old chestnut, OSS and .NET:

Those are all good, well-written posts, and they all make very good points, and I don’t want to debate any of them, but I had a tangential thought on the subject last night while travelling home from the Dot Net Rocks UK Tour event in London. I may be repeating things other people have said, in which case you should definitely tweet me a link to their post with a rude comment about how they said it better.


  • Ruby, Node, etc. are text-based; text-based is easier to extend.
  • .NET is Visual Studio-based; Visual Studio is harder to extend.

.NET is an unusual ecosystem

When groups of developers come together to talk about the state of OSS in .NET, the comparisons were traditionally drawn with Ruby; more recently Node.js has also become a focus for analogy. Both those ecosystems are almost entirely open-source, with lots of healthy competition and innovation, and a genuine sense that if somebody builds a better mousetrap, people will switch to it. “Why isn’t the .NET world more like that?” people ask, and they talk about whether it’s Microsoft’s fault and what they could do to help. What I rarely hear mentioned is the humungous elephant in the room: Visual Studio.

Ruby, Node, Python and most of the other OSS darlings are predominantly CLI-based. There are excellent tools for scaffolding MVC sites, running builds and tests, managing version control or migrating databases; and the thing they all have in common is that they are command-line tools. That is what developers in that ecosystem expect (and, incidentally, is why they prefer Linux and OSX, because they have bash and decent Terminal applications built-in). Text editors are commonplace, from Vim to Sublime Text, and although excellent IDEs are available (thanks mostly to JetBrains) they are luxury accessories rather than fundamental components. I have no idea what the ratio is of Vim users to, say, WebStorm users in the Node.js world, but I wouldn’t be surprised if it came down fairly heavily on the side of Vim, or at least Sublime Text (with or without the excellent Vintageous plug-in).

In the land of .NET, Visual Studio is king. It scaffolds, it builds, it runs tests, it manages version control and it does this really bizarre thing which is instead of migrating databases. You don’t need a CLI, which is lucky, because even though there’s PowerShell now, the Console window it runs in is still a 20-year-old piece of shit.

Disclaimer: I don’t really know about Java, and I don’t really want to, but I suspect it’s different because there are, like, nine different IDEs and even though only one of them doesn’t suck it’s probably still easier to write command line stuff (and also code completion in Java is really just a tiny floating window into a yawning abyss of despair).

The Visual Studio experience

So the majority .NET developers are, first and foremost, Visual Studio users. And Visual Studio with a decent productivity add-on is the best IDE ever, by a considerable margin; yes, it is, and if you try to argue with that in the comments I won’t approve it so don’t even bother. It holds your hand and guides you through things, and it doesn’t demand that you actually remember a whole bunch of stuff, like, in your head. Scaffolding is done with wizards; builds and tests are run at a key-press with colourful graphical output; version control is integrated into the Solution explorer; the database design stuff is all drop-downs and pop-ups.

People complain that Microsoft built Entity Framework instead of embracing NHibernate, but NHibernate never had an Entity Model Designer integrated into Visual Studio (correct me if I’m wrong (Update: I was wrong; MindscapeHQ do an NHibernate designer, albeit a commercial product)). The OSS section of the stands may boo and hiss at the very idea of the Entity Model Designer, let alone the horrible, horrible code that it generated, but it made the ORM concept approachable for a vast swathe of developers who would otherwise have carried on blithely binding web forms to DataSets.

I don’t know whether it would have been realistic for Microsoft to add tooling for NHibernate to Visual Studio than to write their own ORM from scratch, but I suspect writing their own and creating the tooling as they went along was easier.

The same can’t really be said for MSTest, which was a hazardous by-product of the NIH mentality of the time, but it did allow integration with Visual Studio and various frameworks (think “Generate Unit Tests”) in a way that blessing NUnit probably wouldn’t have, at least not without Microsoft developers contributing to that project on company time.

And so on and so on. ASP.NET MVC quietly adds a bunch of features to the IDE, such as “Strongly-typed Razor View with Layout” in the New Items dialog and the “Add Controller…” option on the Controllers folder context-menu. NuGet gets more and more integrated and powerful with each point-release.

How does this affect OSS?

It makes it difficult. It raises the bar, and demands skills and investments of time that most OSS framework or library projects, especially fledgling ones, are unlikely to be willing or able to muster.

In a text-based world where pretty much every tool is a script, it’s easy to compete, because scripts are (relatively) easy to write.

In an IDE world, especially where the IDE’s SDK is baroque and complex and poorly-documented with few good examples available, it’s hard to compete, especially when the people you’re competing with are the people who make that IDE.

Does this mean that .NET OSS is doomed to edge status, an underground movement of which the majority of surface-dwellers are blissfully unaware? Maybe. But there are things that OSS projects could do to improve their chances; things which some are starting to do, in fact.

Things your OSS project should bring to the party

If you’re an application framework, you should at the very least provide Project templates and maybe Item templates. Bonus points for injecting context-specific items into the Solution Explorer menus. If you’re a web framework that supports Razor, find a way to make the IntelliSense work properly in .cshtml files, or use a .razor extension and write your own IntelliSense provider for it. Related: if you’ve invented your own View Engine, Item templates and IntelliSense are expected.

BTW, framework projects: you still shouldn’t expect to gain a huge amount of traction as a percentage of the whole. The overwhelming majority of .NET web development in medium-to-large enterprises still uses ASP.NET Web Forms, and always will, because drag-and-drop and Infrabloodygistics.

If you’re a testing framework, you need to integrate with the built-in Unit Test explorer, as well as ReSharper and other third-party tools. If you can find more ways to provide a lovely hand-holding experience, like SpecFlow’s editor integration and test class generator, then even better.

If you’re a database access library that uses dynamic trickery to do your thing, you still need to make it work with bloody IntelliSense.

And so on.

(Also: documentation, but I'm going to be announcing something about that soon.)

Things Microsoft could do to help

Improve the Visual Studio extensibility story, both in terms of the SDK and the documentation of the SDK. Provide more, and more relevant, examples. And open source the Visual Studio components from your own frameworks for OSS authors to use as a reference. (A good example here is TypeScript; the language, compiler and so on is completely open-source, but the Visual Studio package is closed-source, and I don’t understand why.)

Kudos at this point to Mads Kristensen, a PM on the Microsoft Web Platform team and author of the Web Essentials extension, for open-sourcing that project. The source code for that is an excellent reference for anyone looking to extend Visual Studio at the editor and Solution Explorer levels.

Also, provide MSDN Ultimate subscriptions for established OSS projects, applying the same criteria and license-restrictions as companies like JetBrains and Telerik do for their OSS-supporting licenses. And when the creators of a good OSS project do provide a decent level of integration with Visual Studio, make them Visual Studio MVPs and Insiders so they can access more information about the thing they’re trying to work with.


Update: given some of the comments, I think I should clearly state that I am an MVP (though not for any of my open source stuff) and also a member of the BizSpark+ program, and thus have more MSDN Ultimate subscriptions than I can actually use. I am not advocating this for my own personal benefit, but for the benefit of other open source project maintainers who are not so well-resourced as I am.