Microsoft Open Source Blog

Microsoft Open Source Programs Office (https://opensource.microsoft.com) | REMOTE OR REDMOND, WA, USA | React / Node / Azure / Javascript / Docker | Full time The Microsoft Open Source Programs Office is hiring a Principal Software Engineer to be a technical leader and community manager for ClearlyDefined[0]. We're looking for folks particularly interested in the open source compliance space. Full job description and applications can be done at the job posting[1]. Basic qualifications: - Experience working with open source software projects, especially maintainer and community management roles. - 4-5 years’ experience in software development emphasizing open source and stack technologies such as Node, React, JavaScript, Docker, cloud services, GitHub, Maven, and more. - Excellent community and leadership skills. - Excellent written and verbal communication skills. [0] - https://clearlydefined.io [1] - https://careers.microsoft.com/us/en/job/800721/Principal-Software-Engi…

I don't want to get all righteous, especially considering some excellent projects I've seen from Microsoft such as VSCode, but it feels like you may not understand the culture of the community you're trying to reach. First, let me say that there's nothing wrong with closed-source software. If Microsoft wants to create the best node.js dev and/or production environment ever, and if it does so without violating any OSS licenses (which are mostly MIT, so it's possible), more power to them (/you). However, if you call it an "open source [...] platform", and you host the source code on Github, and you're soliciting and accepting PRs from the public, then you may be creating all sorts of headaches for yourself and others. Yes, people should check the licenses for software they use. But as it is right now, many people will take the project's tagline at face value, and may be reminded of a very different Microsoft if, at some point, some other division at MS decides to crack down on the illegal use of this source code, or when you turn people's contributions into a closed-source project. Edit: the projects also reference Microsoft's "Open Source Code of Conduct", and they are listed at https://opensource.microsoft.com/?keyword=glimpse. I've filed an issue at https://github.com/Glimpse/Home/issues/109

Seems like it's probably a mistake, did you try to contact them? https://opensource.microsoft.com/ https://twitter.com/OpenAtMicrosoft

They are one of the largest contributors to linux, donate $500k annually to Linux foundation (since 2016. Google joined in 2018), VS code, .net is open source to large degree, typescript is open source. Here's a list of their open source projects. https://opensource.microsoft.com/?sort=Stars&keyword=&tag= (Microsoft may be the world's largest open source contributor https://www.techrepublic.com/article/microsoft-may-be-the-worlds-large… (Microsoft becomes 5th largest contributor to linux core https://www.ukfast.co.uk/microsoft-news/impressive-microsoft-contribut…

How is this any different from the sunk cost that's a consequence of going with _any_ particular technology stack? I mean, if you chose Python/Postgres/etc., presumably, you'd have to rewrite/retool everything if you went to a different stack. If you're talking about open vs closed source: the C# compiler (Roslyn) is completely free and open source, as are a number of .NET components: CoreFX - Core foundational libraries, CoreCLR - runtime. As well as PowerShell, VS Code, Typescript, ASP.NET Core, MVC, Blazor, F#, Z3 Theorem Prover, etc. And that's from just the first few pages of their Open Source page: https://opensource.microsoft.com/

Thanks for doing this. This will be the canary that tells us whether Microsoft is really changed like they claim. Since they call themselves "in love with open source" [1] and letting Github "remain an open platform" [2], I expect them to not remove this project from Github. If they do remove it, whatever reason they give about wanting to provide the best possible VSCode experience is bullshit and Github will no longer be a home for open-source projects. [1] https://info.microsoft.com/rs/157-GQE-382/images/Microsoft-loves-Linux… [2] https://open.microsoft.com/2018/06/07/github-acquisition-microsoft-com…

Referencing the companies in the original tweet, each one has a landing page (internal or on Github) for how they contribute to OSS. Making open standards which are cross-compatible between programs doesn't happen overnight, where often community-driven users are a force under which further awareness and adoption are spread. [0] https://opensource.microsoft.com/ [1] https://aws.github.io/ and https://aws.amazon.com/mp/oss/ [2] https://opensource.google.com/

wait, how does go and chrome trump open source c#, f#, vb.net, .net core, typescript, asp.net, visual studio code, monaco, powershell core, mono, and the many, many other things they have open sourced? they’ve gone insane. https://opensource.microsoft.com https://github.com/Microsoft and all of these are active and well managed with microsoft employees engaged in communication.

>Google has been a much stronger supporter of open source That's debatable. According to GitHub, Microsoft is the biggest contributor to open source projects. http://www.businessinsider.com/microsoft-github-open-source-2016-9 In addition, there are quite a few high-profile open source software packages directly from Microsoft. https://opensource.microsoft.com

What metric are we going by? If simply the number of "stars" VSCode easily beats out their other OSS, including Typescript and .NET https://opensource.microsoft.com/?sort=Stars&tag=

> The fact that there can be security issues at the application level is no reason to add memory safety issues to them! > You may well have the resources to fork a process per customer, not have a database pool, not cache etc. its a trade-off with resources needed and performance. This feels like one of those weird things that wind up happening in discussions about a lot of things, including say, renewable energy. People get so hung up about certain details that the discussion winds up going into a direction that really doesn't make sense, and it could only go there incrementally because it would've been very obvious if you followed the entire chain. Please bear with me. Consider the primary problem in the first place: The problem is that we have a bunch of things that are not memory safe, already. Rewriting all of those things is going to take a lot of time and effort. All of these ideas about isolating requests are totally fine, honestly. If you can afford those sorts of trade-offs in your design, then go hog wild. I find many of these architectural decisions to be a bit pointless for reasons I'm happy to dig into in more detail if people really care, but the important thing to understand is that I'm not telling you to not try to isolate requests. I'm just saying that in practice, there are no "legacy" servers that apply this degree of request isolation. They were architected with the assumption that the process would not get RCE'd, and therefore it would require a…

No it's not, and yes it does. This trend on HN that has consisted in wanting to kill the meaning of "open source" as most people understand it is very weird and surprising. I don't understand what is at stake. I have noticed this since one month or so. The vast majority of projects that call themselves open source mean the open source definition as defined by the open source initiative, or something equivalent. You might not like or recognize the OSI and that's fine, but you can't decide what people mean when they say open source. You are the one starting the battle and I don't understand your motives. I just searched for "open source" in a search engine, I'm getting [1,2,3] and lists of "the best open source software". And they are all using the OSD. You are at odds with Wikipedia, IBM, RedHat and with Microsoft, Google, Amazon, Facebook, Apple [4,5,6,7,8], and with everyone else, really. [1] https://en.wikipedia.org/wiki/Open_source [2] https://www.redhat.com/en/topics/open-source/what-is-open-source [3] https://www.ibm.com/en-en/topics/open-source [4] https://opensource.microsoft.com/ [5] https://opensource.google/ [6] https://aws.amazon.com/fr/opensource/ [7] https://opensource.fb.com/ [8] https://opensource.apple.com/

Here’s another overview: https://opensource.microsoft.com/

It is rare that I say this but, thanks MS! Arguably just as, if not more, important is the BASIC that they wrote. That was what they actually wanted to do. DOS just got them the contract with IBM. For decades MS was really a developer tools company with a side biz of writing operating systems and other misc software. They also open sourced that BASIC code too [1]. [1] https://opensource.microsoft.com/blog/2025/09/03/microsoft-open-source…

The official announcement contains many interesting complementary links: https://opensource.microsoft.com/blog/2026/04/28/continuing-the-story-…

Source: https://opensource.microsoft.com/blog/2026/04/28/continuing-the-story-… (https://news.ycombinator.com/item?id=47936462)

This is very neat! Been wondering what people would do with the Zork code now that it is open source [1]. [1]: https://opensource.microsoft.com/blog/2025/11/20/preserving-code-that-…

Blog post: https://opensource.microsoft.com/blog/2025/09/03/microsoft-open-source…

Microsoft's blog post on Hyperlight got my attention a while ago: https://opensource.microsoft.com/blog/2025/02/11/hyperlight-creating-a… I am way out of my depth here, but can anyone make a comparison with the "micro virtual machines" concept?

Not sure how dependent on wasm as such this is, but sub-millisecond cold-starts[1] seems like a pretty compelling argument [1] https://opensource.microsoft.com/blog/2025/03/26/hyperlight-wasm-fast-…

Good question. I think it’s the additional security? From [1]: > Hyperlight is able to create new VMs in one to two milliseconds. While this is still slower than using sandboxed runtimes like V8 or Wasmtime directly, with Hyperlight we can take those same runtimes and place them inside of a VM that provides additional protection in the event of a sandbox escape. [1]: https://opensource.microsoft.com/blog/2024/11/07/introducing-hyperligh…

> Only the copyright owner can sublicense If that were true, then the distribution of OSS would be illegal. If I contribute to an open source project, I have licensed my code to that project. If someone downloads that project, the OSS project has sublicensed my code to them. I doubt there's a CLA in the world that doesn't grant the right to sublicense. For example, here is the CLA for VS Code: https://opensource.microsoft.com/pdf/microsoft-contribution-license-ag… the key bit is: > You grant Microsoft . . . a . . . license . . . to sublicense any or all of the foregoing rights to third parties

It certainly still does run on a Windows flavour, https://techcommunity.microsoft.com/blog/windowsosplatform/azure-host-… However they have been working on something else for specific workloads, https://opensource.microsoft.com/blog/2024/11/07/introducing-hyperligh…

This post may help answer some of your questions: https://opensource.microsoft.com/blog/2024/10/22/detect-and-react-inte… And the project docs may help answer others: https://drasi.io/ Also, the Drasi team are most active over on our discord channel (https://aka.ms/drasidiscord) where we would be happy to answer questions and help you get started using Drasi.

> Nixiesearch uses an S3-compatible block storage (like AWS S3, Google GCS and Azure Blob Storage) Hair-splitting: I don't believe Blob Storage is S3 compatible, so one may want to consider rewording to distinguish between whether it really, no kidding, needs "S3 compatible" or it's a euphemism for "key value blob storage" I'm fully cognizant of the 2017 nature of this, but even they are all "use Minio" https://opensource.microsoft.com/blog/2017/11/09/s3cmd-amazon-s3-compa… which I guess made a lot more sense before its license change. There's also a more recent question from 2023 (by an alleged Microsoft Employee!) with a very similar "use this shim" answer: https://learn.microsoft.com/en-us/answers/questions/1183760/s3-api-sup…

> I personally tend to get cautious when there is a proposal that x will solve the problem that occurred on y date, especially 3 days after the failure. Microsoft has been working on eBPF for a few years at least. https://opensource.microsoft.com/blog/2021/05/10/making-ebpf-work-on-w… https://lwn.net/Articles/857215/ If you're really concerned, they have discussions and communication channels where you're invited to air your concerns. They're listed on their github: https://github.com/microsoft/ebpf-for-windows Who knows, maybe they already have answers to your concerns. If not, they can address them there.

Typescript, vscode, npm, github and more https://opensource.microsoft.com/projects/ They also added a “Sponsor” button to Github which while I have mixed feelings about it, does help open source projects thrive.

I work on an open-source project for Microsoft, and I review and merge community PRs all the time. Nobody pays for the product I work on (or for C# or TypeScript, for that matter). The Contributor License Agreement used on all MSFT open source projects doesn't ask you to transfer your copyright, though it does require submitters to agree to grant a permissive copyright and patent license. IANAL, but the copyright and patent clauses in Microsoft's CLA[0] do not look substantially different from the equivalent clauses in the Apache 2.0 license[1]. [0]: https://opensource.microsoft.com/pdf/microsoft-contribution-license-ag… [1]: https://github.com/rust-lang/rust/blob/master/LICENSE-APACHE#L66

An interesting impact of this discussion is, for me: within my team at work, we're likely to forbid any use of Github co-pilot for our codebase, unless we can get a formal guarantee from Github that the generated code is actually valid for us to use. By the way, code generated by Github co-pilot is likely incompatible with Microsoft's Contribution License Agreement [1]: "You represent that each of Your Submission is entirely Your original work". This means that, for most open-source projects, code generated by Github co-pilot is, right now, NOT acceptable in the project. [1] https://opensource.microsoft.com/pdf/microsoft-contribution-license-ag…

I don't think the list of projects is complete.[1] I specifically know Microsoft's open source initiatives through Microsoft R Open[2], which is not listed on that page. [1] https://opensource.microsoft.com/projects/explore/ [2] https://mran.microsoft.com/open