Today we’re happy to announce that ReactiveUI is joining the .NET Foundation!

ReactiveUI is a composable, cross-platform model-view-viewmodel framework for all .NET platforms that is inspired by functional reactive programming which is a paradigm that allows you to express the idea around a feature in one readable place, abstract mutable state away from your user interfaces and improve improve the testability of your application.

Most modern programming today is basically imperative, meaning it models the traditional fetch-execute cycle of a CPU: perform an instruction, fetch the next one, perform that one, and so on. For decades, programmers have had to mold their brains to fit the paradigm of the CPU. When teams rely on hoping that the behavior that emerges from a program is correct, and that reliance is based on nothing more than a programmer's correctness, you can find yourself in a sticky situation.  You can try and mitigate the costs of imperative programming with things like unit tests or integration tests, but why mitigate the costs when there's a better way?

The ReactiveUI team firmly believes reactive programming is fundamentally a better way to build your applications. Here's a great video that makes the point pretty clearly:

The ReactiveUI website has a lot more information to learn more about the project. They also have a slack community head on over to

We're excited to welcome ReactiveUI join the .NET Foundation. They've got a lot of exciting things planned and we're happy to be part of it!

.NET Summer Hackfest is a .NET Foundation sponsored, community run open source hacking party. We’re almost done with Session 1 and ramping up for Session 2, so here’s some info on what we’ve been up to and how you can get involved.

Here’s the most important part: Session 2 runs from August 7 – August 18 and includes two exciting projects: Brighter and DotVVM. It’s open to everyone, from absolute beginners to experienced .NET open source developers. Here’s a great time to get involved with your .NET open source community!

Session 1 Progress: Keen IO SDK port to .NET Standard

We started with one project for the first session: porting the Keen IO SDK to .NET Standard. Keen IO is a really cool event data platform that’s really developer friendly. At the free level, they give you $20 credit per month, which works out to 2 million streamed events. They also give discounts to OSS projects, and they’ve got open source API libraries for a lot of frameworks.

The team started with a straightforward porting goal, but I pushed them to include some stretch goals to keep them busy. They’ve made great progress, as you can see from the Kanban board below.

Some highlights for this project:

  • The core SDK, tests, and build have been ported to .NET Standard
  • The code is all running on Windows, Ubuntu and MacOS under .NET Core (hooray)
  • Cross-platform Continuous Integration is set up on AppVeyor (for Windows) Travis CI (for Ubuntu and macOS)
  • We learned a lot for the projects we’ll be doing in Sessions 2 and 3 (my selfish goal for this project)
  • We had a one on one call with Immo Landwerth to get some advice on some interesting .NET Standard issues
  • The Keen IO dev team have been phenomenal hosts!
  • Most important for me: we had some great commits from the community around the world, including several pull requests from Tarun and Don

Session 2 Projects Kicking off Monday, August 7: Brighter and DotVVM

If you’ve been keeping an eye on .NET Summer Hackfest but haven’t got involved yet, now is the time! We’ve got two established .NET open source projects run by some well known .NET community leaders. Both are planning some local in-person community events as well.

DotVVM: An Open Source MVVM framework for Web Apps

DotVVM is an innovative MVVM (model-view-viewmodel) front-end web framework that offers a clean programming model, over 25 built-in controls, and support for both “classic” ASP.NET (OWIN) and ASP.NET Core.

Here’s what they’ll be working on and how you can get involved.

Also, if you’re in or near Prague, they’ll be running a full day Hackfest event at the Microsoft office in Prague on Friday, August 11.

Brighter: A Lightweight Command Processor and Dispatcher

Brighter is a Command Processor & Dispatcher implementation that can be used as a lightweight library in other projects. It can be used for implementing Ports and Adapters and CQRS (PDF) architectural styles in .NET. They’ll have some smaller up-for-grabs issues for folks who are getting up to speed as well as some more ambitious work to implement abstractions to facilitate additional middleware such as Redis, Kafka, and Event Store.

We’ll have some more information on how you can get involved in the Brighter hackfest within the next day.

Let’s Do This!

This is your open source .NET Community! Now’s a great time to show up and make an impact!

Beginners, here’s a great chance to get involved and level up your open source .NET skills.

Community leaders, let’s take this chance to build the development community you want to see.

Please join me in welcoming AutoMapper to the .NET Foundation!

AutoMapper has been a popular library in the .NET open source community for a long time. As their site says:

AutoMapper is a simple little library built to solve a deceptively complex problem - getting rid of code that mapped one object to another. This type of code is rather dreary and boring to write, so why not invent a tool to do it for us?

Thanks to Jimmy Bogard and the AutoMapper team for building and actively maintaining this project for so many years! Welcome!

You can read more about AutoMapper, including some a nice getting started tutorial, on their site.

UPDATE: See the Peachpie team's post on joining the .NET Foundation here.

Today, it’s my privilege to welcome Peachpie Compiler to the .NET Foundation.

Peachpie is an open source PHP Compiler to .NET. This innovative compiler allows you to run existing PHP applications with the performance, speed, security and interoperability of .NET.

The Peachpie site includes a lot of exciting examples, including a demonstration running WordPress on .NET with really impressive performance results. We’re excited to have them join the .NET Foundation, and look forward to supporting them!

I’m happy to announce today that Windows Template Studio has joined the .NET Foundation, and congratulate them on their version 1.2 release!

Windows Template Studio is a Visual Studio 2017 Extension that accelerates the creation of new Universal Windows Platform (UWP) apps using a wizard-based experience. The resulting UWP project is well-formed, readable code that incorporates the latest Windows 10 features while implementing proven patterns and best practices. The generated code includes helpful links to Docs, Stack Overflow and blogs to provide useful insights.

It’s also nice that Windows Template Studio templates include some other .NET Foundation projects including MVVM Light and UWP Community Toolkit!

For a nice introduction to Windows Template Studio, check out this 20 minute interview with the team at Build 2017.

Windows Template Studio is a great addition to the .NET Foundation! Get the latest update and get involved in the project here.