Howard van Rooijen

Howard van Rooijen

@hvr.endj.in

Founder @endjin.com Microsoft #MVP for Azure & Developer Technologies. Try to help people and orgs to become the best versions of themselves.

1K followers663 following464 posts

Howard van Rooijen reposted

Howie Hua
@howiehua.bsky.social

Today's date is the last Pythagorean Triple date of our lifetime! (Unless you live through 2105) Here's a really cool fact about how to generate infinitely many Pythagorean triples

Howard van Rooijen
@hvr.endj.in

It might be down to the age demographic, but last night I went to see Marillion and I did not see a single phone being held aloft, bathing everyone in blue light. There was just a building full of people living in the moment, fully engaged and relishing every second for themselves.

Howard van Rooijen
@hvr.endj.in

There's nothing quite like finding out the GitHub stacked PRs are really buggy, and you have 39 stacked PRs that you then have toerge by hand....

Howard van Rooijen reposted

John Reilly
@johnnyreilly.com

This is a fantastic point. Bizarrely we've entered a world in which the model you speak to is as changeable as the land above the Magic Faraway Tree. I'm ready for models with version numbers and something like semver. Documented breaking changes for new releases of models, would be a feature

Azure Weekly@azureweekly.info

Your Cloud AI SLA Tells You Less Than You Think by James Dawson https://endjin.com/blog/cloud-ai-slas-are-not-what-you-think?utm_source=bluesky&utm_medium=social&utm_campaign=newsletter

endjin.comYour Cloud AI SLA Tells You Less Than You Think by James DawsonTraditional cloud SLAs measure API uptime, not behavioural stability. This post talks about how silent AI model drift can quietly break your agents and the questions you might want to ask vendors.

Howard van Rooijen reposted

Azure Weekly
@azureweekly.info

Trying Out WSL Containers: Microsoft's Built-In Alternative to Docker Desktop by Mike Evans-Larah https://endjin.com/blog/trying-out-wsl-containers?utm_source=bluesky&utm_medium=social&utm_campaign=newsletter

endjin.comTrying Out WSL Containers: Microsoft's Built-In Alternative to Docker Desktop by Mike Evans-LarahMicrosoft's new WSL Containers (wslc) promises container management on Windows without Docker Desktop. I tried it with dev containers, Aspire, and Docker Compose - here's what works, what doesn't, and whether you should switch yet.
Howard van Rooijen
@hvr.endj.in

I was a little shocked to see the Wildfire in the New Forest from my daily photo spot. When I was a kid they used to burn the fields after the harvest, but I've not seen anything like this on the horizon before.

Howard van Rooijen
@hvr.endj.in

Even during peak holiday season, is there such a thing as a quiet week? End of month admin, start of month admin, ongoing customer work, a new data & analytics project win, partner calls, and at least 2 separate agentic coding sessions each spawning multiple subagents...

Howard van Rooijen
@hvr.endj.in

Microsoft's new WSL Containers (wslc) promises container management on Windows without Docker Desktop. Mike Evans-Larah tried it with dev containers, Aspire, and Docker Compose - here's what works, what doesn't, and whether you should switch... endjin.com/blog/trying-...

endjin.comTrying Out WSL Containers: Microsoft's Built-In Alternative to Docker Desktop | endjinMicrosoft's new WSL Containers (wslc) promises container management on Windows without Docker Desktop. I tried it with dev containers, Aspire, and Docker Compose - here's what works, what doesn't, and...
Howard van Rooijen
@hvr.endj.in

For the last year I've been suggesting to anyone who'll listen that the northstar / mission of .NET should be ".NET is the best platform for Y" where Y is the workload. This post from @jeffhandley.com is the first time I've seen this articulated in the wild. .NET is the best platform for MCP.

.NET Foundation@dotnetfoundation.org

Announcing v2.0 of the official MCP C# SDK MCP C# SDK v2.0 implements the 2026-07-28 specification with a stateless-first protocol, standardized HTTP headers, and Multi Round-Trip Requests for interactive tools, all while staying backward compatible.

devblogs.microsoft.comAnnouncing v2.0 of the official MCP C# SDK - .NET BlogMCP C# SDK v2.0 implements the 2026-07-28 specification with a stateless-first protocol, standardized HTTP headers, and Multi Round-Trip Requests for interactive tools, all while staying backward comp...
Howard van Rooijen
@hvr.endj.in

New 25 minute talk about Rx .NET v7.0! TOC: - Breaking Change 1: TFMs - TFM Confusion Explained - Breaking Change 2: Nullability - Big Change UI Packages Split - The 95MB Problem - Deployment Results - Source vs Binary Breaking - ReactiveUI Demo endjin.com/what-we-thin...

endjin.comRx.NET v7.0 Released - it could save you 95MB! | endjinRx.NET 7.0 can cut self-contained Windows app deployments by ~95MB by moving WPF/WinForms support out of System.Reactive into optional packages.
Howard van Rooijen
@hvr.endj.in

Finished watching Warrior last night. Such an enjoyable series. Very sad it got cancelled after season 3. Worth seeking out if you enjoyed Deadwood / Hell on Wheels / The Knick.

Howard van Rooijen
@hvr.endj.in

Just making a cuppa and spotted a baby bunny chilling in the sunshine, not a care in the world (unaware of the large numbers of buzzards in the area). Be more bunny.

Howard van Rooijen
@hvr.endj.in

Well, I'm really glad I kicked off the Fable code review of my PR just after dinner - it was still chugging away when I went to bed, and I woke up with the full report, but now Opus 4.8 is going to have to implement it. And my usage has been reset back to 0, it was just about spent.

Howard van Rooijen
@hvr.endj.in

I took my niece, nephew and mother to see The Mandalorian and Grogu yesterday. I don't understand all the negativity around it. We all absolutely loved it. "It's just an overlong TV episode with a bigger budget" - yes, and how is that a bad thing?

Howard van Rooijen reposted

squillace
@squillace.bsky.social

and the docs are up: learn.microsoft.com/en-us/agent-.... This uses precisely the thing @aspenwilder.bsky.social had done over here using monty "python" as a #webassembly component, and it screams: www.linkedin.com/feed/update/...

learn.microsoft.comHyperlight CodeActUse the Hyperlight connector to add CodeAct and sandboxed Python execution to Agent Framework.
squillace@squillace.bsky.social

super excited to see the @cncf.io project #hyperlight and #webassembly start to make defense-in-depth a reality. devblogs.microsoft.com/agent-framew... is the Agent Framework using #wasmtime inside an OS-less microvm to execute python beyond fast with full software AND hardware protection.

devblogs.microsoft.comCodeAct in Agent Framework: Faster Agents with Fewer Model Turns | Microsoft Agent FrameworkExplore the hyperlight codeact agent framework and streamline your tool-calling sequences with enhanced performance.
Howard van Rooijen
@hvr.endj.in

Barry has put a huge amount of work into this! Just in time for his #SQLBits2026 talk (on Saturday). If you're using #MicrosoftFabric or thinking of adopting it, this is very much worth your time (as it significantly changes the costs calculations). endjin.com/blog/fabric-...

endjin.comFabric Performance Benchmarking - Spark versus Python Notebooks | endjinBenchmarking Pandas, PySpark, Polars, and DuckDB on Microsoft Fabric: in-process Python engines run 4-5x cheaper and faster than Spark for common workloads.
Howard van Rooijen
@hvr.endj.in

There are many ways in which I hate "New Outlook" but #1 is the deprecation of RSS. For 20+ years Outlook has been my information portal - email + RSS. I had a single app, that synced data across apps & experiences that kept me informed. Without RSS, an plain email client looses so much value.

Howard van Rooijen reposted

Azure Weekly
@azureweekly.info

Integration Testing #AzureFunctions with Reqnroll and C#, Part 1 - Introduction by Jonathan George #AzureFunctions #Azure endjin.com/blog/integra...

endjin.comIntegration Testing Azure Functions with Reqnroll and C#, Part 1 - Introduction | endjinIf you use Azure Functions on a regular basis, you'll likely have grappled with the challenge of testing them. In the first of a series of posts, we look at some different approaches to testing your functions...
Howard van Rooijen
@hvr.endj.in

@endjin.com has been a remote-first company since 2017. After a few years away travelling around the world, Carmel Eve returned to work in the UK. Carmel talks about how remote flexibility protected her mental health and made that transition possible. endjin.com/blog/returni...

endjin.comReturning to Work After a Career Break: How Remote Work Made It Possible | endjinAfter years away, I returned to work in the UK. Here's how remote flexibility protected my mental health and made that transition possible!
Howard van Rooijen
@hvr.endj.in

I've done a bit of work with OpenCLI - I've got a tool which generates a MCP server from an OpenCLI spec, and one that generates a OpenCLI spec from any CLI. Was surprised to get an issue against DeadCode - a tool to help AI Agents identify dead code - to improve OpenCLI support for a new visualiser

Howard van Rooijen
@hvr.endj.in

We're starting to blog about the approaches we've taken to deliver successful outcomes for AI solutions. It shouldn't surprise anyone that the same rigorous approaches we take for software & data engineering & data science projects are just as effective for Al scenarios endjin.com/blog/2026/03...

endjin.comFrom Prompt Engineering to AI Programming: Building Enterprise-Ready Generative AI Solutions | endjinShift from prompt engineering to AI programming by applying rigorous software engineering principles to your LLM integrations.
Howard van Rooijen
@hvr.endj.in

I very much enjoyed the Matt Dinniman & Jeff Hays event last night in London. I did not enjoy having to leave a packed theatre at 23.00 - mid performance - because SWR has decided the last train service is now at 23:35. Nothing like getting mocked from the stage AND by the audience. BYEEEE 👋