[HN Gopher] Microsoft open-sources LiteBox, a security-focused l...
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       Microsoft open-sources LiteBox, a security-focused library OS
        
       Author : aktau
       Score  : 254 points
       Date   : 2026-02-06 15:13 UTC (7 hours ago)
        
 (HTM) web link (github.com)
 (TXT) w3m dump (github.com)
        
       | aktau wrote:
       | From the GitHub page:
       | 
       | LiteBox is a sandboxing library OS that drastically cuts down the
       | interface to the host, thereby reducing attack surface. It
       | focuses on easy interop of various "North" shims and "South"
       | platforms. LiteBox is designed for usage in both kernel and non-
       | kernel scenarios.
       | 
       | LiteBox exposes a Rust-y nix/rustix-inspired "North" interface
       | when it is provided a Platform interface at its "South". These
       | interfaces allow for a wide variety of use-cases, easily allowing
       | for connection between any of the North--South pairs.
       | 
       | Example use cases include:                 - Running unmodified
       | Linux programs on Windows       - Sandboxing Linux applications
       | on Linux       - Run programs on top of SEV SNP       - Running
       | OP-TEE programs on Linux       - Running on LVBS
        
         | aktau wrote:
         | More links with discussion:
         | 
         | Reddit discussion:
         | https://www.reddit.com/r/linux/comments/1qw4r71/microsofts_n...
         | 
         | Project lead James Morris announcing it on social.kernel.org:
         | https://social.kernel.org/notice/B2xBkzWsBX0NerohSC
        
           | xjamesmorris wrote:
           | FYI, I am not the project lead for Litebox. It is led by
           | Microsoft Research.
        
         | a-dub wrote:
         | is this wslv1.2 (wslv1 redux) in now a more general cross-
         | platform library firewall type thing?
        
       | kvuj wrote:
       | The cargo.lock file is 2200+ lines long. Did they spend a
       | reasonable amount of time auditing these dependencies?
        
         | Andrex wrote:
         | They ran it through Copilot which gave it the all-clear.
        
         | shikon7 wrote:
         | What would be a reasonable amount of time to audit the
         | dependencies?
        
           | kvuj wrote:
           | I would let them decide based on their security policy.
           | 
           | If Microsoft states that they don't have any for a project
           | like this, I would be wary of taking it too seriously.
        
         | adolph wrote:
         | grep 'name = ' ms-litebox-Cargo.lock | wc -l          238
         | 
         | edit:                 grep 'name = ' ms-litebox-Cargo.lock |
         | sort -u | wc -l          221
        
           | dizhn wrote:
           | I've always done 'sort | uniq'. Never bothered to check for
           | the the unique flag to sort. Although 'uniq -c' is quite nice
           | to have.                      -c, --count
           | prefix lines by the number of occurrences
        
             | adolph wrote:
             | Yeah, to see the packages with multiple versions:
             | grep 'name = ' ms-litebox-Cargo.lock | sort | uniq -c |
             | grep -v '1 name' | sort -n
             | 
             | Package windows-sys has the highest number of versions
             | included, 3: 0.59.0, 0.60.2, and 0.61.2.
             | 
             | Edit: Also, beware of the unsorted uniq count:
             | cat <<EOF | uniq -c       > a       > a       > b       > a
             | > a       > EOF        2 a        1 b        2 a
        
               | dundarious wrote:
               | grep -v '1 name' excludes 11, 21, etc., but I take your
               | point.
        
         | CodesInChaos wrote:
         | That's 238 dependencies (counting multiple versions of the same
         | crate).
         | 
         | * Many of them are part of families of crates maintained by the
         | same people (e.g. rust-crypto, windows, rand or regex).
         | 
         | * Most of them are popular crates I'm familiar with.
         | 
         | * Several are only needed to support old compiler versions and
         | can be removed once the MSRV is raised
         | 
         | So it's not as bad as it looks at first glance.
        
         | jrm4 wrote:
         | Given, you know, Microsoft, I'd demand proof even if they said
         | they did.
        
       | anon291 wrote:
       | A library os to me would typically mean it's aimed at hosting a
       | single user program on bare hardware. I don't see that here, but
       | maybe I'm just confused
        
         | richardlblair wrote:
         | The reddit conversation seems to allude to you being correct.
        
         | bri3d wrote:
         | It's both; it's aimed at hosting a single user program on
         | another userspace, but also seems to have its own kernel as
         | well?
         | 
         | The "North" part seems to be what I think you'd traditionally
         | think of as a library OS, and then the "South" part seems to be
         | shims to use various userlands and TEEs as the host (rather
         | than the bare hardware in your example).
         | 
         | I'm really confused by the complete lack of documentation and
         | examples, though. I think the "runners" are the closest thing
         | there is.
        
       | ukuina wrote:
       | No deployment instructions?
        
       | CasualSuperman wrote:
       | With how buggy their flagship OS has become, why would I trust
       | anything else they release to be better? Or even if it does work
       | well now, why should I expect it to stay that way? Microsoft has
       | burned through all possible goodwill at this point, at least for
       | me.
        
         | rafram wrote:
         | This isn't supposed to replace Windows, and it isn't a GUI
         | desktop operating system at all. I doubt anyone working on this
         | has anything to do with the modern Windows desktop UX.
        
           | dspillett wrote:
           | _> This isn 't supposed to replace Windows,_
           | 
           | OP wasn't suggesting it was, just that the lack of quality in
           | one significant area of the company's output leads to a lack
           | of confidence in other products that they release.
        
           | Reddit_MLP2 wrote:
           | but if the host OS is already comprised, what is the point of
           | sandbox inside of it?
        
             | necovek wrote:
             | Maybe we need secure attestation for sandbox to be
             | protected against compromised host :)
             | 
             | It does sound hard, and might need to employ homomorphic
             | encryption with hw help for any memory access after code
             | has been also verifiably unaltered through (uncompromised)
             | hw attestation.
        
         | hudo wrote:
         | UI of Windows is buggy and inconsistent. Kernel and low level
         | stuff are actually very stable and good.
        
           | joe_mamba wrote:
           | _> Kernel and low level stuff are actually very stable and
           | good._
           | 
           | This. A while ago a build of Win 11 was shared/leaked that
           | was tailored for the Chinese government called "Windows G"
           | and it had all the ads, games, telemetry, anti-malware and
           | other bullshit removed and it flew on 4GB RAM. So Microsoft
           | CAN DO IT, if they actually want to, they just don't want to
           | for users.
           | 
           | You can get something similar yourself at home running all
           | the debloat tools out there but since they're not officially
           | supported, either you'll break future windows updates, or the
           | future windows updates will break your setup, so it's not
           | worth it.
        
             | TkTech wrote:
             | Is this not just Windows LTSB/LTSC? Which has been a thing
             | forever.
        
               | joe_mamba wrote:
               | Maybe, could also be that for a 9 figure government
               | contract they'll provide a custom LTSC branch just for
               | you with only the features you want.
        
             | RajT88 wrote:
             | Talked about back in the Vista days publicly (I cannot find
             | the articles now) - Microsoft has commitments to their
             | hardware partners to help keep the hardware market from
             | collapsing.
             | 
             | So they are not incentivized to keep Win32_Lean_N_Mean, but
             | instead to put up artificial limits on how old of hardware
             | can run W11.
             | 
             | I have no insider knowledge here, just this is a thing
             | which get talked about around major Windows releases
             | historically.
        
               | joe_mamba wrote:
               | _> Microsoft has commitments to their hardware partners
               | to help keep the hardware market from collapsing._
               | 
               | Citation needed since that makes no logical sense. You
               | want to sell your SW product to the most common
               | denominator to increase your sales, not to a market of HW
               | that people don't yet have. Sounds like FUD.
               | 
               |  _> but instead to put up artificial limits on how old of
               | hardware can run W11_
               | 
               | They're not artificial. POPCNT / SSE4.2 became a hard
               | requirement starting with Windows 11 24H2 (2024) (but
               | that's for older CPUs), and only intel 8th gen and up
               | have well functioning support for Virtualization-Based
               | Security (VBS), HVCI (Hypervisor-protected Code
               | Integrity), and MBEC (Mode-Based Execution Control).
               | That's besides the TPM 2.0 which isn't actually a hard
               | requirement or feature used by everyone, the other ones
               | are way more important.
               | 
               | So at which point do we consider HW-based security a
               | necessity instead of an artificial limit? With the ever
               | increase in vulnerabilities and attack vectors, you gotta
               | rip the bandaid at some point.
        
               | ssl-3 wrote:
               | Windows 11 is running on my ThinkPad T530. Its CPU is
               | very nearly 14 years old.
               | 
               | What is missing here that was present when this same
               | computer was running Windows 10?
        
               | joe_mamba wrote:
               | _> Windows 11 is running on my ThinkPad T530. Its CPU is
               | very nearly 14 years old._
               | 
               | Yes, you can bypass HW checks to install it on a pentium
               | 4 if you want, nothing new here.
               | 
               |  _> What is missing here that was present when this same
               | computer was running Windows 10?_
               | 
               | All the security features I listed in the comment above.
        
               | ssl-3 wrote:
               | So, if I'm hearing this right:
               | 
               | This computer had the security features that you listed
               | while it was running Windows 10, and now that it is
               | running Windows 11 it is lacking them?
               | 
               | (I'm not trying to be snarky. That's simply an
               | astonishing concept to me.)
        
               | necovek wrote:
               | If anything, Microsoft has a lot of problems because they
               | support a wide variety of crappy hardware and allow just
               | about anyone to write kernel level sw (drivers). Not sure
               | if this changed, but they used to run in the ring0 even.
               | 
               | This was most evident back in the 90s when they shipped
               | NT4: extremely stable as opposed to Win95 which
               | introduced the infamous BSOD. But it supported
               | everything, and NT4 had HW support on par with Linux
               | (i.e. almost nothing from the cheap vendors).
        
             | hilti wrote:
             | Never heard of Windows G .. that sounds exactly what I want
             | for my older Thinkpads :-)
        
               | WarOnPrivacy wrote:
               | > Windows G .. sounds exactly what I want for my older
               | Thinkpads
               | 
               | I'm running 11 IoT Ent LTSC on a some T420; it runs
               | pretty okay.
        
               | qingcharles wrote:
               | I've been starting with Tiny11 and then running the
               | debloat scripts against it. Reduces the memory footprint
               | to about 2GB and have found zero compatibility problems
               | with doing this. You just have to use curl or something
               | to download a browser because you won't even have Edge.
        
             | bcraven wrote:
             | Something similar, or indeed, exactly the same:
             | 
             | https://www.windowscentral.com/software-
             | apps/windows-11/leak...
        
             | drnick1 wrote:
             | Microsoft should just open source Windows at this point.
        
             | workfromspace wrote:
             | I geniunely wonder if Windows G's start menu also use React
             | and if the start menu, right click or Windows Search still
             | sucks in Windows G or not :)
        
               | pjmlp wrote:
               | React Native, halfway between Web and native.
        
           | exceptione wrote:
           | NTFS, not so great.
        
             | p_ing wrote:
             | NTFS is just fine. Stable, reliable, fast, plenty of
             | features for a general purpose file system.
        
               | repelsteeltje wrote:
               | ...But no way can you wrap it into something that looks
               | posix-y from the inside
        
               | p_ing wrote:
               | Why would you want to?
        
               | repelsteeltje wrote:
               | From the article, first use case:
               | 
               | > Example use cases include:
               | 
               | > * Running unmodified Linux programs on Windows
               | 
               | > * ...
               | 
               | That won't work if the unplugged Linux program assumes
               | that mv replaces a file atomically; ntfs can't offer
               | that.
        
               | p_ing wrote:
               | NTFS uses atomic transactions, that's the only way it has
               | the ability to recover after a fault.
               | 
               | You can read more if you wish in 'Inside the Windows NT
               | File System' by Helen Custer, page 15.
        
               | exceptione wrote:
               | Even with Defender etc off, it is not fun. Lots of small
               | file IO brings it on its knees. Some wants to blame the
               | Windows I/O system, I don't know, but what I do know is
               | that when people choose NTFS it is because they haven't
               | an alternative. Nobody chooses it based on its quality
               | attributes. I dare to say there is no NTFS system that is
               | faster than an EXT4 system.
               | 
               | If even MS internal teams rather want to avoid it, it
               | seems like it isn't a great offering.
               | https://news.ycombinator.com/item?id=41085376#41086062
        
               | p_ing wrote:
               | NTFS on Linux should be near-par with ext4 on Linux.
               | 
               | Remember, I said the _file system_ was just fine. It's
               | that extensible architecture above all file systems on NT
               | that causes grief.
               | 
               | The only method to 'turn off' Defender is to use
               | DevDrive, which enforces ReFS, and even then you only get
               | async Defender, it's not possible to completely disable.
        
           | mananaysiempre wrote:
           | > Kernel and low level stuff are actually very stable and
           | good.
           | 
           | In their intended applications, which might or might not be
           | the ones you need.
           | 
           | The slowness of the filesystem that necessitated a whole
           | custom caching layer in Git for Windows, or the slowness of
           | process creation that necessitated adding "picoprocesses" to
           | the kernel so that WSL1 would perform acceptably and still
           | wasn't enough for it to survive, those are entirely due to
           | the kernel's archtecture.
           | 
           | It's not necessarily a huge deal that NT makes a bad
           | substrate for Unix, even if POSIX support has been in the
           | product requirements since before Win32 was conceived. I
           | agree with the MSR paper[1] on fork(), for instance. But for
           | a Unix-head, the "good" in your statement comes with
           | important caveats. The filesystem is in particular so slow
           | that Windows users will unironically claim that Ripgrep is
           | slow and build their own NTFS parsers to sell as the fix[2].
           | 
           | [1] https://lwn.net/Articles/785430/
           | 
           | [2] https://nitter.net/CharlieMQV/status/1972647630653227054
        
             | jph00 wrote:
             | This is not due to slowness of the file system. Native ntfs
             | tools are much faster than Unix ones in some situations.
             | The issue is that running Unix software on windows will
             | naturally have a performance impact. You see the same thing
             | in reverse using Wine on Linux. Windows uses a different
             | design for IO so requires software to be written with that
             | design in mind.
        
               | MadnessASAP wrote:
               | It's pretty typical these days for software, particularly
               | games of the DX9-11 eras to perform better on Wine/Proton
               | then they do under native Windows on the same hardware.
        
               | m132 wrote:
               | > Native ntfs tools are much faster than Unix ones in
               | some situations. The issue is that running Unix software
               | on windows will naturally have a performance impact. You
               | see the same thing in reverse using Wine on Linux.
               | 
               | Not true. There are increasingly more cases where Windows
               | software, written with Windows in mind and only tested on
               | Windows, performs better atop Wine.
               | 
               | Sure, there are interface incompatibilities that
               | naturally create performance penalties, but a lot of
               | stuff maps 1:1, and Windows was historically designed to
               | support multiple user-space ABIs; Win32 calls are broken
               | down into native kernel calls by kernel32, advapi32,
               | etc., for example, similar to how libc works on Unix-like
               | operating systems.
        
             | dgxyz wrote:
             | This is on the mark.
             | 
             | But there's another issue which is what cripples windows
             | for dev! NTFS has a terrible design flaw which is the fact
             | that small files, under 640 bytes, are stored in the MFT.
             | The MFT ends up having serious lock contention so lots of
             | small file changes are slow. This screws up anything Unixy
             | and git horribly.
             | 
             | WSL1 was built on top of that problem which was one of the
             | many reasons it was slow as molasses.
             | 
             | Also why ReFS and "dev drive" exist...
        
             | p_ing wrote:
             | The file system isn't slow. The slowness will be present in
             | any file system due to the file system filters that all
             | file system calls pass though.
        
               | mananaysiempre wrote:
               | Right, by "file system" here I mean all of the layers
               | between the application talking in terms of named files
               | and whatever first starts talking in terms of block
               | addresses.
               | 
               | Also, as far as my (very limited) understanding goes,
               | there are more architectural performance problems than
               | just filters (and, to me, filters don't necessarily sound
               | like performance bankruptcy, provided the filter in
               | question isn't mandatory, un-removable Microsoft
               | Defender). I seem to remember that path parsing is
               | accomplished in NT by each handler chopping off the
               | initial portion that it understands and passing the
               | remaining suffix to the next one _as an uninterpreted
               | string_ (cf. COM monikers), unlike Unix where the slash-
               | separated list is baked into the architecture, and the
               | former design makes it much harder to have (what Unix
               | calls) a "dentry cache" that would allow the kernel to
               | look up meanings of popular names without going through
               | the filesystem(s).
        
             | BrouteMinou wrote:
             | The Windows filesystem isn't slow per se, it's a slowness
             | caused by "a thousand cuts" type of problem.
             | 
             | https://github.com/Microsoft/WSL/issues/873#issuecomment-42
             | 5...
        
         | autoexec wrote:
         | Microsoft doesn't have a very good track record with security
         | or privacy. Maybe it works, but yeah you'll probably get
         | screwed over at some point.
         | 
         | Still, the fact that it's open source is a good thing. People
         | can now take that code and make something better (ripping out
         | the AI for example) or just use bits and pieces for their own
         | totally unrelated projects. I can't see that as anything but a
         | win. I have no problem giving shitty companies credit where its
         | due and they've done a good thing here.
        
         | simonw wrote:
         | Microsoft employ over 100,000 engineers. I'd advise against
         | assuming that everything produced by any of them is bad because
         | of bugs in Windows.
        
           | lysace wrote:
           | This is also still small/unimportant enough not to be
           | poisoned by their broken corporate culture.
        
           | replooda wrote:
           | The criticism was directed at the company's product, not the
           | employees...
        
             | trimethylpurine wrote:
             | The response appears to be pointing out that with so many
             | employees (engineers), it's unlikely that they all work on
             | Windows.
        
               | mcmcmc wrote:
               | And yet they still work for a company that has shown it
               | isn't overly concerned about quality or reliability in
               | its products.
        
               | 1f60c wrote:
               | Thaaat's _capitalism_
        
           | workfromspace wrote:
           | Not op, and I generally agree with your assumption but not
           | for Microsoft, as I don't think it's limited to Windows:
           | 
           | Teams, Office (especially online), One Drive, SharePoint,
           | Azure, GitHub, LinkedIn, all became very shitty and partially
           | unusable with increasing number of weird bugs or problems
           | lately.
        
           | ddtaylor wrote:
           | They seem to be alienating a lot of their users right now in
           | a lot of different products. There's a significant surge in
           | open source software right now and Linux and all the people
           | that are coming over are a bit more than usual. Their
           | customer base seems tired of the game.
        
           | dvfjsdhgfv wrote:
           | The problems with Windows today have nothing to do with bugs
           | but with the strategic vision of Nadella.
        
           | solarkraft wrote:
           | This is not about individual employees. It's in the nature of
           | being an employee to be beholden to what's incentivized by
           | their company's management and structure.
        
         | necovek wrote:
         | Windows is ultimately a lot more complex, and not open source.
         | This also builds on the Linux ecosystem, so even if it comes
         | from Microsoft, I imagine engineering culture is different from
         | that on Windows and especially their online platforms (that's
         | even worse than Windows if you ask me!).
        
         | dooglius wrote:
         | MSR is a somewhat independent org; you should be making
         | predictions based on other MSR projects
        
         | BrouteMinou wrote:
         | Microsoft US a massive corporation with so many people,
         | business units, departments.
         | 
         | A comment like yours is just like saying: "I know a buggy open-
         | source software, why would I trust that other open-source
         | project? The open-source community burned all possible
         | goodwill".
        
         | b00ty4breakfast wrote:
         | I'm not defending MS in any capacity, but this library is open
         | for viewing if you were so inclined.
        
       | sscarduzio wrote:
       | Can it replace Wine to run Windows apps on Linux?
        
         | marklar423 wrote:
         | IIUC, if you have the source you can recompile said Windows app
         | with LiteBox to statically link in the Windows OS kernel
         | dependencies, so it'll run on any compatible processor
         | regardless of OS (since it won't be making syscalls anymore).
         | It's a unikernel basically.
         | 
         | That's the theory, but I don't know how far LiteBox is along to
         | supporting that workflow.
        
         | johannes1234321 wrote:
         | They say
         | 
         | > It focuses on easy interop of various "North" shims and
         | "South" platforms.
         | 
         | For replacing wine on Linux the "North" would be kernel32 API
         | or similar, the "South" would be Linux sys all API.
         | 
         | However this is meant as a library, thus require linking the
         | Windows program to it and eine is more than the system
         | interface, it has all the GUI parts etc of win32 API
        
       | cbondurant wrote:
       | at first I thought library OS might have meant an OS meant for
       | use at a library.
       | 
       | Honestly far less interesting to know I was wrong.
        
         | KPGv2 wrote:
         | yeah, same here, I was like "wow what an interesting side to
         | their business, a whole operating system intended to serve
         | public and academic libraries!"
        
         | rendaw wrote:
         | Is it not? You link the "library os" and you no longer need an
         | os (when running in a supervisor) IIUC.
        
           | stackghost wrote:
           | I think parent poster was referring to an actual library,
           | i.e. where you would borrow books.
           | 
           | That's also what I thought this was, and came to the comments
           | expecting to see something neat about why libraries might
           | need bespoke operating systems.
        
         | noumenon1111 wrote:
         | Me too. Honestly I was vibing on nostalgia for this:
         | https://en.wikipedia.org/wiki/Dynix_(software)
        
       | loufe wrote:
       | The lack of integrated sandboxing in windows compared to
       | android/iphone is still frankly unacceptable. I've become
       | increasingly paranoid about running any application on Windows
       | (not that your average linux distro is even remotely better) and
       | yet Apple and Google seem to be far, far ahead in user
       | permissions (especially with GrapheneOS, god bless that team) and
       | isolation of processes.
       | 
       | Consumers and businesses deserve better. It's crazy to me that in
       | 2026 Notepad++ being compromised means as much potential damage
       | as it does, still.
        
         | digiown wrote:
         | The sandboxing on mobile platforms puts the OS vendor in a
         | special position to enforce a monopoly on apps and features.
         | Apple enforces it aggressively, while Google only reluctantly
         | so far. It also prevents the user from exerting full control of
         | the system. Apple does it by locking things down directly,
         | while Google punishes you for owning your devices with
         | attestation.
         | 
         | There has to be a better way. I think Linux's flatpak is a
         | reasonable approach here, although the execution might be
         | rather poor. I want a basic set of trusted tool that I can do
         | anything with, and run less trusted tools like GUI programs in
         | sandboxes with limited filesystem access.
        
           | wat10000 wrote:
           | Those are policy decisions not really connected to the
           | sandboxing technology. They control what sort of signing the
           | system will accept and make it so that it only runs things
           | they approve, and they only approve things that are sandboxed
           | a certain way. The exact same sandboxing could be used with a
           | system where an admin user can decide what gets to run and
           | what kind of sandboxing is required for each thing.
        
         | pjmlp wrote:
         | UWP, and MSIX on Win32 via Appstore.
         | 
         | There is also sandboxing configuration via Intune for
         | enterprises.
        
         | malkia wrote:
         | There are containers, and one of their users is the Windows
         | Sandbox - https://learn.microsoft.com/en-
         | us/windows/security/applicati...
        
         | newsoftheday wrote:
         | > I've become increasingly paranoid about running any
         | application on Windows (not that your average linux distro is
         | even remotely better)
         | 
         | Linux excels over Windows in the area of security by a wide
         | margin, I have no qualms about running an app on Linux versus
         | Windows, any day of the week.
        
           | madspindel wrote:
           | > Linux excels over Windows in the area of security by a wide
           | margin
           | 
           | No, this is wrong but might be true if you are talking about
           | Linux package manager vs. Random Windows .exe on internet.
           | But if you are talking about Secure Boot, encrypted disk,
           | sudo etc. Windows is more secure but it looks like
           | https://amutable.com/ will make Linux more secure like
           | Windows.
           | 
           | Edit: Some insecure things on Linux: Dbus (kwallet etc.),
           | sudo, fprint, "secure boot".
        
       | gdevenyi wrote:
       | What is a 'library OS'?
        
         | zamadatix wrote:
         | https://en.wikipedia.org/wiki/Operating_system#Library
        
         | charles_f wrote:
         | I think that's an OS in the form of a library, like Wine for
         | example. From what I get from the description it allows you to
         | run programs on your real OS and make it see a cut down API to
         | your actual system to reduce the attack surface.
        
         | bri3d wrote:
         | It's a library that is linked to in place of an operating
         | system - so whatever interface the OS provided
         | (syscalls+ioctls, SMC methods, etc.) ends up linked / compiled
         | into the application directly, and the "external interface" of
         | the application becomes something different.
         | 
         | This is how most unikernels work; the "OS" is linked directly
         | into the application's address space and the "external
         | interface" becomes either hardware access or hypercalls.
         | 
         | Wine is also arguably a form of "library OS," for example
         | (although it goes deeper than the most strict definition by
         | also re-implementing a lot of the userland libraries).
         | 
         | So for example with this project, you could take a Linux
         | application's codebase, recompile it linked to LiteBox, and run
         | it on SEV-SNP. Or take an OP-TEE TA, link it to LiteBox, and
         | run it on Linux.
         | 
         | The notable thing here is that it tries to cut the interface in
         | the middle down to an intermediate representation that's
         | supposed to be sandbox-able - ie, instead of auditing and
         | limiting hundreds of POSIX syscalls like you might with a
         | traditional kernel capabilities system, you're supposed to be
         | able to control access to just a few primitives that they're
         | condensed down to in the middle.
        
           | kccqzy wrote:
           | > So for example with this project, you could take a Linux
           | application's codebase, recompile it linked to LiteBox
           | 
           | If you have to recompile, you might as well choose to
           | recompile to WASM+WASI. The sandboxing story here is
           | excellent due to its web origins. I thought the point of
           | LiteBox is that recompilation isn't needed.
        
             | bri3d wrote:
             | Looking more closely, it looks like there are some "North"
             | sides (platforms) with ABI shims (currently Linux and OP-
             | TEE), but others (Windows, for example), would still
             | require recompilation.
             | 
             | > If you have to recompile, you might as well choose to
             | recompile to WASM+WASI.
             | 
             | I disagree here; this ignores the entire swath of
             | functionality that an OS or runtime provides? Like, as just
             | as an example, I can't "just recompile" my OP-TEE TA into
             | WASM when it uses the KDF function from the OP-TEE runtime?
        
               | kccqzy wrote:
               | I had previous experience with WASM on TEE. Just use the
               | foreign function interface. Remember WASM isn't native
               | code so you still need other native code to run WASM
               | (such as wasmtime), and you can import other native
               | functions into WASM through the runtime.
        
       | tombert wrote:
       | I'm not sure I understand what a library OS is; can someone here
       | elaborate?
        
         | greatgib wrote:
         | My understanding of this is that it is a sandbox. Providing a
         | common interface like if it was an OS for the program to run
         | inside, but avoiding the program to use the OS directly.
         | 
         | What is unclear is if it uses its own common ABI or if you use
         | the one of the host os. I don't know why but from the project
         | description I have a little bit of feeling that this is another
         | vibe coded project.
        
         | wrs wrote:
         | A library OS is an OS that is linked directly to your program
         | instead of being a separate program accessed through a syscall
         | to kernel mode. About the same as a "unikernel", but a more
         | recent term.
         | 
         | Basically it lets your program run directly on a hypervisor VM,
         | though this one will also run as a Linux/Windows/BSD process.
        
       | hypfer wrote:
       | "We did not find any viable commercial use for it, but maybe you
       | will."
        
       | burnermore wrote:
       | Baaah! Microsoft, security-focused in a single sentence!
        
       | bendover690 wrote:
       | Cool
        
       | throwoutway wrote:
       | No mention of starting with a design specification & then tied to
       | formal verification the whole way?
       | 
       | It sounds interesting and a step forward (never heard of library
       | Os itll now), but why won't this run into hundreds of the same
       | security bugs that plague Windows if it's not spec'd and
       | verified?
        
         | anon291 wrote:
         | People seem to believe writing things in rust means it's
         | correct.
        
       | R_Spaghetti wrote:
       | I'm not sure whether Microsoft, the makers of Windows 95 (after
       | which I stopped taking them seriously), are the sharpest tool in
       | the box when it comes to security.
        
       | ementally wrote:
       | Copilot
       | 
       | https://github.com/microsoft/litebox/blob/main/.github/copil...
        
         | pjmlp wrote:
         | To be expected, given how many organisations now require
         | employees to use AI if they want to meet their OKRs, especially
         | all that sell AI tools.
        
           | outofpaper wrote:
           | What's dumb, on top of everything, is needing to store non
           | special standard operating procedures in specific AI folders
           | and files when wanting to work with AI tooling.
        
             | WorldMaker wrote:
             | Copilot today supports the top-level AGENTS.md approach as
             | well, which seems to be the cross-tool "standard".
        
         | embedding-shape wrote:
         | > Extremely simple changes do not require explicit unit tests.
         | 
         | I haven't used Copilot much, because people keep saying how bad
         | it is, but generally if you add escape hatches like this
         | without hard requirements of when the LLM can take them, they
         | won't follow that rule in a intuitive way most of the time.
        
           | sandos wrote:
           | Yeah, I tried various very sane-looking instrucions file when
           | starting to use copilot 6 months ago. Turned out it was not
           | really useful. It mostly follows the rules anyway, but it
           | also often forgot to. So turns out, especially with the fast
           | turnaround with models today, it was better to just forego
           | these instructions files.
        
           | pjmlp wrote:
           | It is kind of alright, I use mostly on VS when coding C# or
           | C++, for code completions, error analysis, check code quality
           | and such.
           | 
           | As agent, or writing everything for me, not yet.
        
             | bwat49 wrote:
             | the $10 plan makes a great backup to claude or codex and
             | the inline completions are nice
        
       | ho_schi wrote:
       | Another layer (ouch) to abstract away Windows (ouch * ouch).
       | 
       | Use Linux or BSD and ignore that approach for _Vendor Lock-in*
       | into their "library OS"._
        
       | 5o1ecist wrote:
       | Hmmm. Another, admittedly interesting, step towards the complete
       | digital lockdown. Isolate and virtualize everything, now also
       | governed by AI!
       | 
       | I wonder if they, the industry as a whole, eventually will make
       | being able to freely use a PC a subscription, bastardizing
       | "freedom" completely.
        
       | runjake wrote:
       | For others as lost as I am and want the tl;dr:
       | 
       | A library OS is an operating system design where traditional OS
       | services are provided as application-linked libraries, rather
       | than a single, shared kernel serving all the programs.
        
       | cmrdporcupine wrote:
       | I know we're not supposed to complain about comment quality, but
       | -- I came here to look for interesting technical analysis but
       | instead it's Slashdot level snipes about Microsoft the company.
       | And yes, I also dislike Windows and Microsoft generally but this
       | looks like a very interesting project and I'm frankly frustrated
       | at the level of discussion here, it's juvenile. This has nothing
       | to do with Windows, and it looks like most people didn't even
       | read past the title.
       | 
       | I'll play with this later today after work and see how mature it
       | is and hopefully have something concrete and constructive to say.
       | Hopefully others will, too.
        
         | BrouteMinou wrote:
         | I am with you on that. HN is becoming a "14 years old edgy
         | mini-tech" Facebook.
         | 
         | "Microsoft bad, Linux good" kind of comments are all over the
         | place. There is no more in depth discussions about projects
         | anymore. Add the people linking their blogs only to sell you
         | thier services for an imaginary problem, and you get HN 2026.
         | 
         | It's maybe the time to find another tech media. If you know
         | one, I would be glad to know.
        
       | bg24 wrote:
       | Would be nice to see an OCI runtime and if it can give high-
       | performant I/O as opposed to other we have today (eg. Gvisor).
        
       | mlacks wrote:
       | Library Operating System (LibOS) is a type of operating system
       | that runs in the address space of applications, allowing for a
       | small, fixed set of abstractions to connect the library OS to the
       | host OS kernel. This approach offers the promise of better system
       | security and more rapid independent evolution of OS components.
       | LibOS can run significant applications, such as Microsoft Excel,
       | PowerPoint, and Internet Explorer, with significantly lower
       | overhead than a full VM. It can also address many of the current
       | uses of hardware virtual machines at a fraction of the overheads.
       | 1
       | 
       | LibOS is lightweight, with extremely short startup time, and can
       | be used to run Linux programs, making it a versatile option for
       | various applications. It is designed to provide compatibility and
       | sandboxing without the need for VMs, making it a lightweight
       | alternative to containers and VMs. 1
       | 
       | The Library Operating System for Linux was announced on the Linux
       | kernel mailing list, indicating its official recognition and
       | support within the Linux community.
        
         | HendrikHensen wrote:
         | Thanks, ChatGPT.
        
           | salvesefu wrote:
           | The GPT found this and thought it was relevant: "an
           | introduction of library operating system for Linux" -
           | https://lwn.net/Articles/637658/
        
         | sneak wrote:
         | It runs linux programs, not PowerPoint or Excel.
        
       | dzonga wrote:
       | Microsoft gonna release a windows flavored Linux Distro soon ;)
        
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