Maybe someone more familiar with operating systems kernels can answer this: Is Darwin really all the exiting? It is different from both the BSD kernels and Linux, but less so than Windows. Other than the ability to run macOS applications (assuming you can clone the libraries and APIs from macOS) is there some benefit of Darwin that I'm not seeing?
I honestly think the kernel interface is by far the easiest part of building a MacOS compat layer. The userland is gigantic, super complex, and totally closed source. That's the hard part.
AFAIK all macos software only talks to the kernel via userland APIs - so there's no particular benefit to basing ravynOS on XNU anyway. (Just the opinion of a layman.)
Most kernels are kind of the same really. Some have slightly fancier inter-process communication. Leading to my all-time favorite YouTube video, an explainer on Android IPC cut like a spy thriller. I'm not even joking: https://www.youtube.com/watch?v=Fb4UoqXPEtI
from the faq:
> Is this... legally sketchy?
No. Consider projects like ReactOS, a from-scratch effort to create an OS compatible with Microsoft Windows, GNUstep, which provides an open implementation of Cocoa APIs and other things, or Darling, a compatibility layer for running Darwin (macOS) binaries on Linux. ravynOS is similar and stands on the shoulders of many such projects.
as far as i understand it, most companies don’t bother sending cease and desists to projects you’ve never heard of. the fact that the aforementioned projects have avoided the banhammer of Apple should not be an indication that a successful MacOS clone would receive the same treatment.
but on the other hand, maybe that’s a champagne problem. if you can make a macos clone good enough to get the attention of Apple, you’ve already done something incredible.
I think the better example is actually GNU, which endured several challenges as a clean room implementation of unix. I think this is legally sound, but IANAL.
Everyone gets to name their projects for their own reasons. If the pitch is basically an “alternate apple” macOS, I would have chosen one of the other other (alternate) apple varieties as the root of my OS. Missed opportunity I guess.
Real apple-people would'nt consider this anyways. Open source geeks is were they can get traction. Seems like there is plenty of us that would like fbsd quality and vertical integration to the desktop level. There is effort but no breakthroughs.
Why using Discord for comms? Is there anyone who hasn't hit the max 100 "servers" years ago? I've been [lightly] using Discord since 2015 - I'm at the point where I just simply won't even consider trying to narrow down which "server" I can leave so as to join a new one, unless it's something pretty important to make it worth that time sink.
I'm sort of surprised that development is still on X86 instead of moving over to ARM, it looks like the only builds for ARM are for raspberry pi - I know about Asahi but I would have thought that these darwin-based projects would have a leg up on booting even the latest hardware, is Apple not updating darwin anymore?
ARM is great. Love it. There are tons of chips that all do things differently, much more so than x86. Plus the booting mechanisms are a PITA to figure out, debugging is tricky, etc - and that's a single target. x86 isn't particularly elegant given its years of cruft and questionable design decisions but at least it's quasi-consistent (yes, lots of "well actually" possible; I'm speaking broadly).
The ISA on ARM is better, IMO, than x86 but the surrounding ecosystem is hellishly fragmented. Just my $0.02. makes it difficult for OSdevers to find an 'in' to a wider ARM audience. rpi is a great entry point.
You're using open-source Apple code (Darwin) and aiming for Cocoa API compatibility. How are you handling the legal side? Apple's APIs and frameworks are proprietary. Are you reimplementing them from scratch, or using something like GNUstep?
> Developers can port existing Cocoa applications with minimal changes.
I wonder how big the actual gap between close to Cocoa App compatibility and full app compatibility is? Being able to run MacOS apps natively would unlock a huge barrier to adoption here.
Imagine the world where open-source is collaborating instead of fragmenting. Single Linux distribution, single compartibility layer for other OSes, single graphics API, single package manager...
I get where you're coming from ivenjermakov, but the root cause of why we have a Linux, why Unix even existed, why Woz & Jobs created Apple, and so forth, is because creative, smart people want to break the hold of "common stuff".
Not to diss you, but these kind of questions ("Why another distro?", "Why another language?", "Why another ssh server/client/framework"? and so forth) have been asked zillions of times already, and the answer is always the same: the current offerings were not enough, for whatever definition of "enough" was at the time, and those offerings were tied down by whatever social structure or framework that did not work for these creative folks. I love that we have the freedom to explore with technology in the way we do.
I mean, yes, that might get more folks working on a single project - which _might_ lead to shipping more quickly (might - more devs doesn't always equal speed). But I think what we'd end up with is Gnome; something that works fairly well, yet the committee won't allow simple things that the community wants. So we have the whole, "fine, I'll fork this project and add it myself" followed by, "why don't you spend your time HELPING the project instead of creating your own". It sounds a bit like a doom-loop.
I'm kinda on the opposite end of the spectrum. I love this world where 45 people try to race toward the same goal. Sometimes the best ideas win. Sometimes the fastest to the first goal wins. Sometimes everyone gives up. Sometimes we have competing standards we have to sift through. It's a mess, but it's a beautiful mess.
Most people aren't interested in cooperating. The neat thing about collaboration is that work can be shared without cooperation. Free software is inherently anarchist. Sure, there are several successful cooperative organizations, but they all benefit primarily from the collaboration they do with everyone else, and vice versa.
That world is terrible. Thank deity no one has the power to actually inflict and enforce their particular bankrupt oppressive idea of the one true world on everyone else.
Variety and change is basically the definition of life itself. Uniformity and stasis are pretty good definitions of death.
Kooky offshoots and dead-ends are not waste, they are the very definition of life.
Imagine a world without life? Sure, absoulutely do imagine that, so that you can understand how and why you would never want that and should never suggest it, and know exactly how to respond to anyone who comes along and tries to float this genius idea of efficiency.
So many people in these comments talking about this project like it's pitching itself as a ready to go replacement for MacOS... why are you expecting screenshots, this is a tiny project of ambitious scale that is only 5 years old. What they have achieved is brilliant.
Perhaps the biggest reason is that the existing FOSS OS world has little to offer for people who like a Mac-style desktop. It's possible to customize DEs to have a very shallow visual resemblance but the details are all wrong, with Windows, legacy Linux desktops, and even mobile operating systems (in e.g. the case of GNOME) exerting the greater bulk of design influence.
The question might then, "why not make this a DE instead?" to which the answer is that Mac users also like how the underpinnings of the OS work (or have worked in older releases) and would like to continue to use their favorite Mac apps, which isn't going to happen as long as any traditional Linux distribution is involved. Mac apps also have a design ethos that's rare among current native Linux apps, which drives demand for alternatives.
To do this properly it really needs to be a whole-OS endeavor.
That's what this is. Darwin isn't installable today. Apple just dumps a bunch of source code. Previous attempts at making Darwin bootable didn't go far and had no GUI.
why do anything? why Linux? why FreeBSD? why Mac at all? Why build your own wind turbine when corporations make large ones? Why build a cyclekart when you own a car? Why workout when everyone's going to die?
With that mindset, everything is useless and nothing has a point. Have I made my point?
Maybe someone more familiar with operating systems kernels can answer this: Is Darwin really all the exiting? It is different from both the BSD kernels and Linux, but less so than Windows. Other than the ability to run macOS applications (assuming you can clone the libraries and APIs from macOS) is there some benefit of Darwin that I'm not seeing?
XNU has some interesting features.
It’s Mach based, so it has Mach ports, which are an IPC system that is fairly heavily used by macOS.
It has DriverKit, which is a C++ framework for drivers that’s got morecsuppirt than the usual Unix driver model.
Mach-O does more than ELF, and enables the two-layer namespacing that makes macOS able to manage dynamic linking dependencies better than ELF.
Nothing really earth-shattering but interesting enough. And far easier to build a macOS environment on than FreeBSD.
I honestly think the kernel interface is by far the easiest part of building a MacOS compat layer. The userland is gigantic, super complex, and totally closed source. That's the hard part.
AFAIK all macos software only talks to the kernel via userland APIs - so there's no particular benefit to basing ravynOS on XNU anyway. (Just the opinion of a layman.)
Most kernels are kind of the same really. Some have slightly fancier inter-process communication. Leading to my all-time favorite YouTube video, an explainer on Android IPC cut like a spy thriller. I'm not even joking: https://www.youtube.com/watch?v=Fb4UoqXPEtI
I don't think it's all that exciting. The hybrid BSD/mach personalities is somewhat interesting, as are some of the available mach machineries.
It's been a stable foundation for several of the most successful operating systems in history though
Related. Others?
New OS aims to provide (some) compatibility with macOS - https://news.ycombinator.com/item?id=45997212 - Nov 2025 (165 comments)
RavynOS Finesse of macOS. Freedom of FreeBSD - https://news.ycombinator.com/item?id=38485596 - Dec 2023 (176 comments)
RavynOS – Finesse of macOS, freedom of FreeBSD - https://news.ycombinator.com/item?id=32492514 - Aug 2022 (366 comments)
I think any desktop operating systems has to present itself with at least a single screenshot. Why not one in the entire page?
And now that I have walked over the whole website: Why not a single screenshot anywhere?
from the faq: > Is this... legally sketchy? No. Consider projects like ReactOS, a from-scratch effort to create an OS compatible with Microsoft Windows, GNUstep, which provides an open implementation of Cocoa APIs and other things, or Darling, a compatibility layer for running Darwin (macOS) binaries on Linux. ravynOS is similar and stands on the shoulders of many such projects.
as far as i understand it, most companies don’t bother sending cease and desists to projects you’ve never heard of. the fact that the aforementioned projects have avoided the banhammer of Apple should not be an indication that a successful MacOS clone would receive the same treatment.
but on the other hand, maybe that’s a champagne problem. if you can make a macos clone good enough to get the attention of Apple, you’ve already done something incredible.
Wine and Proton are more popular than all of these examples combined and even have corporate sponsors, yet Microsoft hasn’t tried to stop them.
I think the core of this is google vs oracle case. I think they'll be in the clear unless they hit some specific (design?) patents.
I think the better example is actually GNU, which endured several challenges as a clean room implementation of unix. I think this is legally sound, but IANAL.
Microsoft definitely know about ReactOS.
Everyone gets to name their projects for their own reasons. If the pitch is basically an “alternate apple” macOS, I would have chosen one of the other other (alternate) apple varieties as the root of my OS. Missed opportunity I guess.
Real apple-people would'nt consider this anyways. Open source geeks is were they can get traction. Seems like there is plenty of us that would like fbsd quality and vertical integration to the desktop level. There is effort but no breakthroughs.
Why using Discord for comms? Is there anyone who hasn't hit the max 100 "servers" years ago? I've been [lightly] using Discord since 2015 - I'm at the point where I just simply won't even consider trying to narrow down which "server" I can leave so as to join a new one, unless it's something pretty important to make it worth that time sink.
Seems at least one of the same developers works on both PureDarwin and ravynOS: https://www.puredarwin.org/news/The-Road-to-20-5-0.html (This is the first time I've heard of the latter.)
I'm sort of surprised that development is still on X86 instead of moving over to ARM, it looks like the only builds for ARM are for raspberry pi - I know about Asahi but I would have thought that these darwin-based projects would have a leg up on booting even the latest hardware, is Apple not updating darwin anymore?
Kernel dev here (my own project):
ARM is great. Love it. There are tons of chips that all do things differently, much more so than x86. Plus the booting mechanisms are a PITA to figure out, debugging is tricky, etc - and that's a single target. x86 isn't particularly elegant given its years of cruft and questionable design decisions but at least it's quasi-consistent (yes, lots of "well actually" possible; I'm speaking broadly).
The ISA on ARM is better, IMO, than x86 but the surrounding ecosystem is hellishly fragmented. Just my $0.02. makes it difficult for OSdevers to find an 'in' to a wider ARM audience. rpi is a great entry point.
Here's macOS 26.5's XNU: https://github.com/apple-oss-distributions/xnu/tree/ac9718fb... Could just be what the devs have available, if they're really already going to the trouble to target RPi?
You're using open-source Apple code (Darwin) and aiming for Cocoa API compatibility. How are you handling the legal side? Apple's APIs and frameworks are proprietary. Are you reimplementing them from scratch, or using something like GNUstep?
Good luck! There are many attempts at doing something similar. We can't really see anything to judge it by, yet.
> Developers can port existing Cocoa applications with minimal changes.
I wonder how big the actual gap between close to Cocoa App compatibility and full app compatibility is? Being able to run MacOS apps natively would unlock a huge barrier to adoption here.
>but we're not a fan of the ever-closing hardware and ecosystem
What has changed about Apple's ecosystem vis a vis openness, hardware, or the 'ecosystem'?
The macOS ecosystem is pretty much the same as it has been since 1997
The Tn chip.
Prior to that, modern Macs were just PCs. Then Apple started to introduce, and then depend upon, their unique hardware.
Then the ARM migration using proprietary CPUs and GPUs really kicked it up a level. The OS relies on the hardware, which is unique to Apple now.
a lot of the kernel extensions are closed source proprietary. The core is still open but a lot of what makes modern Mac, Mac, are those kexts.
Would be nice to have a screenshot in the overview page
Imagine the world where open-source is collaborating instead of fragmenting. Single Linux distribution, single compartibility layer for other OSes, single graphics API, single package manager...
I get where you're coming from ivenjermakov, but the root cause of why we have a Linux, why Unix even existed, why Woz & Jobs created Apple, and so forth, is because creative, smart people want to break the hold of "common stuff".
Not to diss you, but these kind of questions ("Why another distro?", "Why another language?", "Why another ssh server/client/framework"? and so forth) have been asked zillions of times already, and the answer is always the same: the current offerings were not enough, for whatever definition of "enough" was at the time, and those offerings were tied down by whatever social structure or framework that did not work for these creative folks. I love that we have the freedom to explore with technology in the way we do.
If we had that, many people would yearn for a cambrian explosion of diverse software running in unique niches trying out different ideas.
What a weird idea. It's not like there was a shortage of walled gardens to go bury yourself in.
I mean, yes, that might get more folks working on a single project - which _might_ lead to shipping more quickly (might - more devs doesn't always equal speed). But I think what we'd end up with is Gnome; something that works fairly well, yet the committee won't allow simple things that the community wants. So we have the whole, "fine, I'll fork this project and add it myself" followed by, "why don't you spend your time HELPING the project instead of creating your own". It sounds a bit like a doom-loop.
I'm kinda on the opposite end of the spectrum. I love this world where 45 people try to race toward the same goal. Sometimes the best ideas win. Sometimes the fastest to the first goal wins. Sometimes everyone gives up. Sometimes we have competing standards we have to sift through. It's a mess, but it's a beautiful mess.
Imagine a world where there's no innovation because everyone just accepts the current standard instead of trying something weird.
Why would a single Linux distribution be good?
You are confusing collaboration with cooperation.
Most people aren't interested in cooperating. The neat thing about collaboration is that work can be shared without cooperation. Free software is inherently anarchist. Sure, there are several successful cooperative organizations, but they all benefit primarily from the collaboration they do with everyone else, and vice versa.
That world is terrible. Thank deity no one has the power to actually inflict and enforce their particular bankrupt oppressive idea of the one true world on everyone else.
Variety and change is basically the definition of life itself. Uniformity and stasis are pretty good definitions of death.
Kooky offshoots and dead-ends are not waste, they are the very definition of life.
Imagine a world without life? Sure, absoulutely do imagine that, so that you can understand how and why you would never want that and should never suggest it, and know exactly how to respond to anyone who comes along and tries to float this genius idea of efficiency.
So many people in these comments talking about this project like it's pitching itself as a ready to go replacement for MacOS... why are you expecting screenshots, this is a tiny project of ambitious scale that is only 5 years old. What they have achieved is brilliant.
At the top of Project Goals is “Clean Design”. It would be nice to have screenshots.
The wiki is impossible to read on mobile, due to the sidebar.
It will be interesting to see how much further (or not) some open source projects like this can get using meaningful AI driven development.
Another one? What happened to the other one that was called ... (quick Google) ... Hello System?
[flagged]
Please don't fulminate on HN. The guidelines make it clear we're trying for something better here. https://news.ycombinator.com/newsguidelines.html
Perhaps the biggest reason is that the existing FOSS OS world has little to offer for people who like a Mac-style desktop. It's possible to customize DEs to have a very shallow visual resemblance but the details are all wrong, with Windows, legacy Linux desktops, and even mobile operating systems (in e.g. the case of GNOME) exerting the greater bulk of design influence.
The question might then, "why not make this a DE instead?" to which the answer is that Mac users also like how the underpinnings of the OS work (or have worked in older releases) and would like to continue to use their favorite Mac apps, which isn't going to happen as long as any traditional Linux distribution is involved. Mac apps also have a design ethos that's rare among current native Linux apps, which drives demand for alternatives.
To do this properly it really needs to be a whole-OS endeavor.
> when you could run Darwin
That's what this is. Darwin isn't installable today. Apple just dumps a bunch of source code. Previous attempts at making Darwin bootable didn't go far and had no GUI.
I dunno you could definitely do a "wine but for macos" kind of implementation, e.g., https://www.darlinghq.org/ without breaking IP laws
I've always been shocked by the lengths of time people will commit to proving wrong the folks who tell them "you can't do that."
why do anything? why Linux? why FreeBSD? why Mac at all? Why build your own wind turbine when corporations make large ones? Why build a cyclekart when you own a car? Why workout when everyone's going to die?
With that mindset, everything is useless and nothing has a point. Have I made my point?
... or flowers for the grave? :)