F# Online
@fsharponline.bsky.social
Supporting the worldwide #fsharp community via online channels
https://hachyderm.io/@fsharponline
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https://hachyderm.io/@fsharponline
https://x.com/fsharponline
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F# Online
@fsharponline.bsky.social
· Nov 12
F# Online is now moved to Bluesky (as well as Mastodon, YouTube), and will no longer amplify content posted on X.
Here's an F# starter pack on Bluesky go.bsky.app/SZQgDn8
Here's an F# starter pack on Bluesky go.bsky.app/SZQgDn8
Reposted by F# Online
Hello #fsharp anyone knows working versions of file system provider or FTP provider? github.com/dsyme/FtpTyp... Maybe with help of LLMs this could be extended to be a package?📦
Btw what about MCP server type Provider ? 🙃💚🦔🔥
Btw what about MCP server type Provider ? 🙃💚🦔🔥
GitHub - dsyme/FtpTypeProviderExample: Creating a type provider
Creating a type provider. Contribute to dsyme/FtpTypeProviderExample development by creating an account on GitHub.
github.com
November 7, 2025 at 5:21 PM
Hello #fsharp anyone knows working versions of file system provider or FTP provider? github.com/dsyme/FtpTyp... Maybe with help of LLMs this could be extended to be a package?📦
Btw what about MCP server type Provider ? 🙃💚🦔🔥
Btw what about MCP server type Provider ? 🙃💚🦔🔥
Reposted by F# Online
Go stroustrup 🚀🚀🚀
Hi #fsharp we *might* consider changing a default in Fantomas: github.com/fsprojects/f...
Please let us know what you think.
Please let us know what you think.
[Poll] Consider changing the default of fsharp_multiline_bracket_style · Issue #3200 · fsprojects/fantomas
Hello everyone, I recently had a conversation about how Fantomas formats records by default (fsharp_multiline_bracket_style = cramped). There’s a configuration setting for this: fsharp_multiline_br...
github.com
November 9, 2025 at 8:08 PM
Go stroustrup 🚀🚀🚀
Reposted by F# Online
#fsharp performance over time for a simple processing of a list of records:
member this.Test() =
data
|> Seq.ofList
|> Seq.filter(fun x -> x.Id % 2 = 0)
|> Seq.map(fun x -> x.Id)
|> Seq.sum
member this.Test() =
data
|> Seq.ofList
|> Seq.filter(fun x -> x.Id % 2 = 0)
|> Seq.map(fun x -> x.Id)
|> Seq.sum
September 30, 2025 at 4:37 PM
#fsharp performance over time for a simple processing of a list of records:
member this.Test() =
data
|> Seq.ofList
|> Seq.filter(fun x -> x.Id % 2 = 0)
|> Seq.map(fun x -> x.Id)
|> Seq.sum
member this.Test() =
data
|> Seq.ofList
|> Seq.filter(fun x -> x.Id % 2 = 0)
|> Seq.map(fun x -> x.Id)
|> Seq.sum
Reposted by F# Online
October 1, 2025 at 2:28 PM
Reposted by F# Online
Does #fsharp need file-based apps like C#?. Join us next Friday for a new session where Martin will showcase a prototype for "dotnet run app.fs"-like functionality.
More info: amplifyingfsharp.io/sessions/202...
More info: amplifyingfsharp.io/sessions/202...
Does F# need file-based apps | Amplifying F#
amplifyingfsharp.io
October 3, 2025 at 12:09 PM
Reposted by F# Online
F# Weekly #40, 2025 - Microsoft Agent Framework (Preview) #fsharp sergeytihon.com/2025/10/04/f...
F# Weekly #40, 2025 – Microsoft Agent Framework (Preview)
Welcome to F# Weekly, A roundup of F# content from this past week: News Introducing Microsoft Agent Framework (Preview): Making AI Agents Simple for Every Developer – .NET Blog Grok 4 is now …
sergeytihon.com
October 4, 2025 at 8:27 PM
F# Weekly #40, 2025 - Microsoft Agent Framework (Preview) #fsharp sergeytihon.com/2025/10/04/f...
Reposted by F# Online
More thoughts after making some progress on this #fsharp project: TDD feels kinda obsolete in the face of DDD, and #GitHubCopilot just seems to accelerate that trend. I start by creating some domain types, then writing the public API functions that manipulate them. 1/3
Using #fsharp + Fable for the core domain logic and view state while sticking with React + TypeScript + Three.js for the outer shell of the app turned out to be a really solid choice. I got the core visualizations and interactions working with little fuss.
Unit testing on the other hand… 1/3
Unit testing on the other hand… 1/3
Update on this experiment: #GitHubCopilot hallucinated a library that doesn't seem to exist: Feliz.ReactThreeFiber. That was really the linchpin of making the all-F# option feasible. I don't want to be in the business of maintaining bindings for a library I don't control (or even a subset of it). 1/
October 8, 2025 at 6:43 AM
More thoughts after making some progress on this #fsharp project: TDD feels kinda obsolete in the face of DDD, and #GitHubCopilot just seems to accelerate that trend. I start by creating some domain types, then writing the public API functions that manipulate them. 1/3
Reposted by F# Online
@kenbonny.net I'm watching your talk on F# and I guess I found a bug 😅
If drone is null then you should not use drone.Id in the error message.
Let me know if you'd like my feedback on your talk.
Go #fsharp!
If drone is null then you should not use drone.Id in the error message.
Let me know if you'd like my feedback on your talk.
Go #fsharp!
October 9, 2025 at 12:43 PM
@kenbonny.net I'm watching your talk on F# and I guess I found a bug 😅
If drone is null then you should not use drone.Id in the error message.
Let me know if you'd like my feedback on your talk.
Go #fsharp!
If drone is null then you should not use drone.Id in the error message.
Let me know if you'd like my feedback on your talk.
Go #fsharp!
Reposted by F# Online
F# Weekly #42, 2025 - JetBrains .NET Days Online 2025 #fsharp sergeytihon.com/2025/10/11/f...
F# Weekly #41, 2025 – JetBrains .NET Days Online 2025
Welcome to F# Weekly, A roundup of F# content from this past week: News Preparing for the .NET 10 GC (DATAS) – .NET Blog Developer and AI Code Reviewer: Reviewing AI-Generated Code in .NET &#…
sergeytihon.com
October 11, 2025 at 8:41 PM
F# Weekly #42, 2025 - JetBrains .NET Days Online 2025 #fsharp sergeytihon.com/2025/10/11/f...
Reposted by F# Online
Reposted by F# Online
F# and C#: Deep Integration for Modern Development #shorts: F# and C# have shared edges and deep integration for 20 years. Users benefit from doing things within a strongly typed API. Policy choices are defined as an enumeration inside of the React app as well as in the backend. #FSharp #CSharp…
F# and C#: Deep Integration for Modern Development #shorts
F# and C# have shared edges and deep integration for 20 years. Users benefit from doing things within a strongly typed API. Policy choices are defined as an enumeration inside of the React app as well as in the backend. #FSharp #CSharp #React #API #Integration
www.youtube.com
October 16, 2025 at 11:43 PM
Reposted by F# Online
We're pretty excited about the idea of a @cloudflare.social "native" edge compute story for #fsharp. We've put together a few proposals for some of the work we have in the lab, and hope to be rolling out segments of it through the end of the year. speakez.tech/blog/spec-st...
The SPEC Stack: A Proposal
A unified approach to modern web and distributed 'edge' deployment
speakez.tech
October 17, 2025 at 1:35 PM
We're pretty excited about the idea of a @cloudflare.social "native" edge compute story for #fsharp. We've put together a few proposals for some of the work we have in the lab, and hope to be rolling out segments of it through the end of the year. speakez.tech/blog/spec-st...
Reposted by F# Online
Our Victor CLI tool is a play on words for the idea that Hugo templates should be fair game from bringing into the #fsharp framework. speakez.tech/blog/victor-...
Victor: A Tool for Managing the SPEC Stack
A View Beyond Static Site Generation to a New Wave of Edge Computing
speakez.tech
October 17, 2025 at 1:37 PM
Our Victor CLI tool is a play on words for the idea that Hugo templates should be fair game from bringing into the #fsharp framework. speakez.tech/blog/victor-...
Reposted by F# Online
F# Weekly #42, 2025 - Hi, Victor & .NET 10 RC2 #fsharp sergeytihon.com/2025/10/18/f...
F# Weekly #42, 2025 – Hi, Victor & .NET 10 RC2
Welcome to F# Weekly, A roundup of F# content from this past week: News Announcing .NET 10 Release Candidate 2 – .NET Blog Announcing the .NET Security Group – .NET Blog .NET and .NET F…
sergeytihon.com
October 18, 2025 at 10:10 AM
F# Weekly #42, 2025 - Hi, Victor & .NET 10 RC2 #fsharp sergeytihon.com/2025/10/18/f...
Reposted by F# Online
⚡️ F# Weekly #42, 2025 Highlights .NET 10 RC2 and Victor
🏷️ #devdigest #dotnet #net #fp #fsharp
https://devdigest.today/goto/4965
🏷️ #devdigest #dotnet #net #fp #fsharp
https://devdigest.today/goto/4965
F# Weekly #42, 2025 – Hi, Victor & .NET 10 RC2
Welcome to F# Weekly, A roundup of F# content from this past week: News Announcing .NET 10 Release Candidate 2 – .NET Blog Announcing the .NET Security Group – .NET Blog .NET and .NET F…
devdigest.today
October 18, 2025 at 11:00 AM
⚡️ F# Weekly #42, 2025 Highlights .NET 10 RC2 and Victor
🏷️ #devdigest #dotnet #net #fp #fsharp
https://devdigest.today/goto/4965
🏷️ #devdigest #dotnet #net #fp #fsharp
https://devdigest.today/goto/4965
Reposted by F# Online
Strong, expressive types removes the need for many kinds of parameterized tests.
Instead the compiler works as the test - if it doesn't conform to the definition, the code won't even compile.
Reason #5 F# sucks: Your buggy code won't even compile
hamy.xyz/blog/2025-06...
#fsharp
Instead the compiler works as the test - if it doesn't conform to the definition, the code won't even compile.
Reason #5 F# sucks: Your buggy code won't even compile
hamy.xyz/blog/2025-06...
#fsharp
7 Reasons F# Sucks
Date: 2025-06-18 | build | create | csharp | fsharp | tech |
hamy.xyz
October 18, 2025 at 4:54 PM
Strong, expressive types removes the need for many kinds of parameterized tests.
Instead the compiler works as the test - if it doesn't conform to the definition, the code won't even compile.
Reason #5 F# sucks: Your buggy code won't even compile
hamy.xyz/blog/2025-06...
#fsharp
Instead the compiler works as the test - if it doesn't conform to the definition, the code won't even compile.
Reason #5 F# sucks: Your buggy code won't even compile
hamy.xyz/blog/2025-06...
#fsharp
Reposted by F# Online
Welcome to the #microsoft #dependency Hell (tm) of #dotnet / #fsharp
Thanks for absolutely nothing...
Thanks for absolutely nothing...
October 21, 2025 at 5:58 PM
Welcome to the #microsoft #dependency Hell (tm) of #dotnet / #fsharp
Thanks for absolutely nothing...
Thanks for absolutely nothing...
Reposted by F# Online
Learn #fsharp programming from notebooks 📓 github.com/fcolavecchia...
GitHub - fcolavecchia/fp-course-public: Make F# your first programming language
Make F# your first programming language. Contribute to fcolavecchia/fp-course-public development by creating an account on GitHub.
github.com
October 22, 2025 at 5:14 PM
Learn #fsharp programming from notebooks 📓 github.com/fcolavecchia...
Reposted by F# Online
Improvements in #fsharp performance over time, big boost in speed with .NET 8 working with a sequence on a linked list:
.NET10 -> 3.2us
.NET9 -> 4.0us
.NET8 -> 4.0us
.NET6 -> 9.1us
.NET Framework 4.81 -> 10.5us
.NET10 -> 3.2us
.NET9 -> 4.0us
.NET8 -> 4.0us
.NET6 -> 9.1us
.NET Framework 4.81 -> 10.5us
October 23, 2025 at 11:06 AM
Improvements in #fsharp performance over time, big boost in speed with .NET 8 working with a sequence on a linked list:
.NET10 -> 3.2us
.NET9 -> 4.0us
.NET8 -> 4.0us
.NET6 -> 9.1us
.NET Framework 4.81 -> 10.5us
.NET10 -> 3.2us
.NET9 -> 4.0us
.NET8 -> 4.0us
.NET6 -> 9.1us
.NET Framework 4.81 -> 10.5us
Reposted by F# Online
In the next lab from my Tiny Systems course, you learn how type inference in ML-like languages works and write your own Hindley-Milner inference algorithm!
🎞️ Watch the videos: www.youtube.com/watch?v=FUFQ...
⌨️ Get the #fsharp code: github.com/tpetricek/ti...
🎞️ Watch the videos: www.youtube.com/watch?v=FUFQ...
⌨️ Get the #fsharp code: github.com/tpetricek/ti...
TinyHM 4.1 - How type inference in ML works
YouTube video by Tomas Petricek
www.youtube.com
October 23, 2025 at 7:58 PM
In the next lab from my Tiny Systems course, you learn how type inference in ML-like languages works and write your own Hindley-Milner inference algorithm!
🎞️ Watch the videos: www.youtube.com/watch?v=FUFQ...
⌨️ Get the #fsharp code: github.com/tpetricek/ti...
🎞️ Watch the videos: www.youtube.com/watch?v=FUFQ...
⌨️ Get the #fsharp code: github.com/tpetricek/ti...
Reposted by F# Online
Try #fsharp for scripts and tests at your corporate job, make small intro to colleagues and brake the monotony 🤫💚🦔 youtu.be/tqq_Nb59ADE?...
FP Beginners: ALL Basic F# Types You NEED TO KNOW in 5 Minutes!
YouTube video by About Clean Code
youtu.be
October 24, 2025 at 5:25 PM
Try #fsharp for scripts and tests at your corporate job, make small intro to colleagues and brake the monotony 🤫💚🦔 youtu.be/tqq_Nb59ADE?...
Reposted by F# Online
Reposted by F# Online
⚡️ NuGet.org adds native Sponsorship links
🏷️ #devdigest #dotnet #net #fp #fsharp
https://devdigest.today/goto/4986
🏷️ #devdigest #dotnet #net #fp #fsharp
https://devdigest.today/goto/4986
F# Weekly #43, 2025 – Sponsorship on NuGet.org & TinyHM
Welcome to F# Weekly, A roundup of F# content from this past week: News Announcing Sponsorship on NuGet.org – .NET Blog Upgrading to Microsoft Agent Framework in Your .NET AI Chat App –…
devdigest.today
October 26, 2025 at 7:30 AM
⚡️ NuGet.org adds native Sponsorship links
🏷️ #devdigest #dotnet #net #fp #fsharp
https://devdigest.today/goto/4986
🏷️ #devdigest #dotnet #net #fp #fsharp
https://devdigest.today/goto/4986
Reposted by F# Online
Testing C# with F# one of the easy ways to get started with #fsharp at work and have some more colleagues and friends get used to it > ijrussell.github.io/posts/testin...
Testing C# with F#
Did you know that in modern .Net Solutions, projects using different .Net languages can happily co-exist? This means that you can use the best tool for the job such as F# for your domain logic and C# ...
ijrussell.github.io
October 27, 2025 at 3:34 PM
Testing C# with F# one of the easy ways to get started with #fsharp at work and have some more colleagues and friends get used to it > ijrussell.github.io/posts/testin...