Welcome to F# Weekly,

A roundup of F# content from this past week:

News

• F# in .NET 11 Preview 2 – Release Notes
• Safe Clean Architecture
• RFC: How should Fantomas handle lambda expressions that would change semantics on a single line?

Microsoft News

• .NET 11 Preview 2 is now available! – .NET Blog
• Modernize .NET Anywhere with GitHub Copilot – .NET Blog
• .NET 10.0.5 Out-of-Band Release – macOS Debugger Fix – .NET Blog
• .NET and .NET Framework March 2026 servicing releases updates – .NET Blog
• Extend your coding agent with .NET Skills – .NET Blog
• Aspire Conf is Coming! Join us Live on March 23 | Aspire Blog
• Build a real-world example with Microsoft Agent Framework, Microsoft Foundry, MCP and Aspire – Microsoft for Developers
• Announcing the Azure Skills Plugin | All things Azure
• Visual Studio Code 1.111
• Visual Studio Dev Essentials: Free, Practical Tools for Every Developer  – Visual Studio Blog

Videos

• Llama.fs – YouTube
• Clef Language – WebView and Native Application Rendering – YouTube
• Blazor Community Standup – ASP.NET Core & Blazor updates in .NET 11 Preview 2 – YouTube
• .NET AI Community Standup: Real-World AI Agent Architecture in .NET – YouTube
• Demystifying Workflows with Microsoft Agent Framework – YouTube
• AI-First Mobile Development: Live Coding with Copilot and .NET MAUI – YouTube

Blogs

• Samir Parikh: Higher Order Functions in F#
• Samir Parikh: Functions in F#
• Why I Hope I Get to Write a Lot of F# in 2026 · cekrem.github.io
• PartitionWith in C# | Celso Jr
• MOTHER, Metaprogramming, and the Meta Language – Ben Copeland

Highlighted projects

• dbrattli/Fable.Actor: F# Actors for Fable and Beam
• WillEhrendreich/SageFs: Sage Mode for F# development — REPL with solution or project loading, Live Testing for FREE, Hot Reload, and session management.
• goswinr/Earcut: The fastest and smallest polygon triangulation library. Ported to F# from Mapbox
• adz/CodecMapper: High-performance, AOT-friendly serialization for F# built around explicit schemas

New Releases

• FSharp.Core 11.0.100
• Fastoch 0.11.0
• Fidelity.CloudEdge.Runtime 0.1.7
• Fidelity.CloudEdge.Management 0.1.7
• NBomber 6.3.0
• FAkka.Akka.Persistence.FSharp 1.5.62
• FSharp.Compiler.Service 43.12.201
• FSharp.Data 8.1.0
• SignalCandy 0.3.2
• SageFs 0.6.163
• Str 0.23.0
• ArrayT 0.26.0
• ResizeArrayT 0.26.0
• Earcut 3.0.21
• CodecMapper 0.1.0
• StarFederation.Datastar 1.2.1
• FSharp.Control.AsyncSeq 4.8.0
• FSharp.Formatting 22.0.0-alpha.2
• fantomas 8.0.0-alpha-007
• Fable 5.0.0-rc.3
• AgentNet 1.0.0-rc.4

That’s all for now. Have a great week.

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Comment

I spent a little time updating and cleaning up the iOS Dev Directory this week and it reminded me that I’ve not talked about it here in a while.

The changes I made are relatively minor, but they include a design and wording refresh across the whole site, dark mode support, many more options for showing what social media or profile you attach to your name¹, and improved instructions on how to add a site. I also moved it to its own GitHub organisation and open sourced the website itself, something which was private until now.

The directory has never been a flashy project, but I still think it’s really important that it exists.

Getting people to know about a new blog is hard, especially if you don’t have a large social media following. Having somewhere to list your site is important, and even more so if you include your RSS feed. My personal RSS process immediately subscribes me to any new sites added to the directory, and I know others also have it set up this way. There are also aggregator sites that pull content from the directory’s OPML files.

I started the site in 2018, almost 8 years ago with the intention of broadening the set of people who I subscribed to when reading posts for this newsletter, and it’s certainly been successful at that. There are now almost 1,000 sites listed, and the data file repository has had almost 1,300 pull requests. That said, because it’s not a “destination” site, it always needs an occasional push here to remind people it exists.

So, with that in mind, if your blog isn’t listed then please add it, but let’s take it one step further. If you know of anyone who blogs but isn’t in the directory, or if you found an interesting site recently that isn’t included, add those too! I’d love to push that number of sites over 1,000 in the next week.

I do have another reason to write about the iOS Dev Directory. You might have noticed I’ve missed publishing a few issues of this newsletter recently, and it’s because I have rather a lot going on. I’d love some help with iOS Dev Directory from anyone who thinks a site like this is important. Either reply to the email if you’re subscribed that way or it’s dave at this domain if you’re reading on the web. Drop me a mail and we’ll chat. Thanks!

– Dave Verwer

News

I noticed something at the end of this month’s “Hello Developer” post from Apple that I hadn’t noticed before, and which I’ve been wishing for for years! Scroll right down to the bottom and there’s a “New Docs” section! I still wish there was a better portal or way to find out about all new and updated documentation, but this is a really good start to highlight some significant changes throughout the month. Looking at the back issues, it seems it’s been there for a while, too! Shame on me for not noticing.

Tools

I haven’t used Apple’s Network Link Conditioner in quite a few years now, so I was surprised when Ash Hood let me know about his new throttling tool. Turns out the official link conditioner hasn’t had as much love as it maybe needed over the years, and a tool like this might come as a welcome surprise if you’ve been struggling with it. 👍

Code

I really loved this post from Steve Troughton Smith. He wasn’t new to using LLMs for coding tasks, but he admits that he had been “sleeping on the shift that is already well underway in our industry”. What I love most about what he wrote is that it’s all experiments. Writing a Windows app, creating data to fit a specific (and niche) file format, and more. It’s a great post.

When I read the title of Daniel Devesa Derksen-Staats’s latest post, I expected it to be filled with little side-stories about how other games get accessibility wrong. Instead, I enjoyed reading an entirely positive post about how to do it right. Bravo, Daniel, that’s exactly how to do it!

I was so excited for Passkeys when they first got announced. What a wonderful idea, but I hate the experience of using them once they reached the real world. I think part of my issue is that I have multiple apps and also the operating system all trying desperately to make me create a passkey, and it always happens when I’m logging into something and just want to get something done. I actively avoid them now, so the constant nagging is just irritating. I also can’t imagine how a “normal” person copes with them if they baffle me. 😬 Is it just me that feels this way?

Aaaaannnyway, apologies for the rant! If you decide to, or are asked to implement them, then Natascha Fadeeva has exactly the article for you. The article is great, despite my thoughts on the underlying tech.

And finally...

Have you ever tried to explain what you do?? I really like this. ❤️

Ranjan Roy from Margins is back for our weekly discussion of the latest tech news. We cover: 1) Backlash against AI & specifically Sam Altman's comments about AI as a utility 2) Is this because people are worried about AI taking their jobs? 3) NBC poll shows AI is one of the least popular things in the U.S. 4) YouGov poll shows broadly negative feelings toward AI 5) Pew finds datacenters are very unpopular 6) Consequences of AI's unpopularity 7) Nvidia GTC preview: A rallying cry for AI 8) Could Jensen Huang be the guy that turns this around? 9) Amazon's AI code is messing things up 10) McKinsey's AI tool hacked 11) Meta can't get its act together with Avocado delayed 12) Should Meta's AI use Google's Gemini tech

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