F# Weekly #50, 2025 – Making of A Programming Language

Welcome to F# Weekly,

A roundup of F# content from this past week:

News

• .NET 10 Networking Improvements – .NET Blog
• Microsoft Learn MCP Server Elevates Development – .NET Blog
• Implementing Cross-Platform In-App Billing in .NET MAUI Applications – .NET Blog
• Making Windows Terminal awesome with GitHub Copilot CLI – Microsoft for Developers
• Join us for AI Dev Days – December 10-11 – Microsoft for Developers
• Aspire Integrations, Batteries Included | Aspire Blog
• Streamlining your Git workflow with Visual Studio 2026 – Visual Studio Blog

🚀 Excited to announce SharpIDE – A Modern, Cross-Platform IDE for .NET!I'm thrilled to share my latest open-source project, just in time for .NET 10: SharpIDE, a brand new IDE for .NET, built with .NET and Godot! 🎉🔗 Check it out on GitHub: github.com/MattParkerDe……

— Matt Parker (@mattparker.dev) 2025-11-11T23:24:13.521Z

Videos

• Type Inference: Write Less Code, Catch More Bugs.
• Excel: The World’s Most Successful Functional Programming Platform by Houston Haynes
• 🎄 Advent of code 2025 in F# – day 07
• 🎄 Advent of code 2025 in F# – day 08
• TinyExcel 7.1 – Technical dimensions of spreadsheets
• TinyExcel 7.2 – Architecture and F# events
• TinyExcel 7.3 – Code structure and step-by-step guide
• ASP.NET Community Standup – Build agentic UI with AG-UI and Blazor
• On .NET Live – On .NET Live | Patterns in Messaging Systems
• .NET Day on Agentic Modernization

Let's build a Programming Language – together!The goal? Combine the developer experience of Python with the safety of TypeScript.In Episode 0: Syntax + Type Inference📺 http://www.youtube.com/watch?v=fSRT…#TypeInference #TypeScript #CSharp #FSharp #Rust #Haskell

— SchlenkR (@schlenkr.bsky.social) 2025-12-13T08:58:15.904Z

Blogs & FsAdvent

• Implementing my own bookmark manager – Jozsef Uri
• F# in Production: What I Know After Four Years – Ben Copeland
• Comprehensive Guide to SRTP Gymnastics – Millennium
• I like my F# code type annotation-free – Urs Enzler
• Adding Goal Seek to Quipu (and helping Santa with it!) – Mathias Brandewinder
• Tagless Final in F# – John Azariah
  • Tagless Final in F# – Part 1: Froggy Tree House
  • Tagless Final in F# – Part 2: Maps, Branches, and Choices
  • Tagless Final in F# – Part 3: Goals, Threats, and Getting Stuck
  • Tagless Final in F# – Part 3: Goals, Threats, and Getting Stuck
  • Tagless Final in F# – Part 5: Verifying the Elevator
  • Tagless Final in F# – Part 6: The Power of Tagless-Final: Code as Model
• Making of A Programming Language – Making of A Programming Language
• Baker: A Key Ingredient to Firefly | SpeakEZ Technologies
• Show Notes: The World’s Most Successful FP Platform | SpeakEZ Technologies

F# vNext

• mutable on any binding · Issue #1457 · fsharp/fslang-suggestions
• [WIP]: MethodImplOption.Async support by TheAngryByrd · Pull Request #19065 · dotnet/fsharp

Highlighted projects

• speakeztech/Firefly: A compiler that brings F#’s elegance and precision to systems programming through MLIR and various backends
• cariandrum22/Xanthos: Type-safe F# wrapper for the JRA-VAN JV-Link COM API, providing functional access to Japanese horse racing data.
• mrtz-j/Saturn.OpenTelemetry: A OpenTelemetry Extension for Saturn

New Releases

• Akka.FSharp 1.5.57
• FSharp.Azure.Quantum 1.3.2
• FCQRS.Model 5.0.1
• Xanthos 0.1.0
• CloudflareFS.Management 0.1.0
• CloudflareFS.Runtime 0.1.0
• Feliz.Template 5.0.0
• Hedgehog 2.0.0
• Hedgehog.Xunit.v3 2.0.0
• FSharp.Core 10.0.101
• FSharp.Compiler.Service 43.10.101
• Fantomas.FCS 8.0.0-alpha-001
• Paket 10.0.0-alpha011

Hm… Serena #fsharp

— Sergey Tihon 🦔🦀 (@sergeytihon.com) 2025-12-08T22:13:13.971Z

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

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