Show HN: Lume 0.2 – Build and Run macOS VMs with unattended setup

140 points by frabonacci a month ago on hackernews | 38 comments

whinvik | a month ago

Sorry for the naive question but specifically for running Claude on a sandbox, why do people decide to use lume as opposed to running it on Docker?

[OP] frabonacci | a month ago

Docker on Mac runs Linux containers inside a Linux VM - you can't run macOS in Docker. So if you need Claude / Codex / OpenCode to interact with:

- macOS GUI apps (Xcode, Numbers, Safari, etc.) - macOS desktop automation (screenshots, mouse/keyboard input, accessibility APIs) - macOS CI/CD (building iOS/macOS apps, running XCTest)

...you need an actual macOS VM, which is what Lume provides.

fishtacos | a month ago

I wonder what the additional layer of virtualization changes with respect to this in a project like this one: https://github.com/dockur/macos

The unattended setup is a large improvement, which also begs the question: Mac OS doesn't have an unattended.xml alternative for its installer?

happyopossum | a month ago

macOS has unattended setup options via MDM or Apple Configurator…

easton | a month ago

Can you do zero touch without having an Apple Business account (so, a DUNS number) and a MDM?

I thought this was a silly way to do it too, but upon reflection I don’t know if you can zero touch setup a Mac without registering a device in DEP.

[OP] frabonacci | a month ago

re: unattended setup.

You're both right - Apple's official zero-touch setup requires MDM + DEP, which needs Apple Business Manager (and yes, a DUNS number).

But for VMs specifically, DEP doesn't work anyway - VMs don't have real serial numbers that can be enrolled in Device Enrollment Program.

VNC-based setup automation is the only practical option - it's what the ecosystem has converged on for macOS VMs. Lume connects to the VM's VNC server and programmatically tabs, clicks, types through Setup Assistant.

arianvanp | a month ago

I wish the virtualization framework would allow you to simulate your own MDM stuff. Would be very useful for integration testing MDM implementations themselves...

[OP] frabonacci | a month ago

re: https://github.com/dockur/macos

A closer comparison here is Lumier, which provides a "Docker-like" interface to spin up VMs with a noVNC server: https://cua.ai/docs/lume/guide/advanced/lumier/docker

The key difference: dockur/macos uses QEMU+KVM, which only works on Linux hosts. It can't run on macOS hardware since Apple doesn't expose KVM. See: https://github.com/dockur/macos/issues/256

cmckn | a month ago

I tried to set up a macOS VM recently so I could run an old version of iTunes to manage my iPods. I found it nearly impossible to even download an installer for older versions of the OS, and could never get it working. Where can one acquire an IPSW for, say, macOS Mojave? My understanding is this is not the same thing as the “Install macOS.app”?

samtheprogram | a month ago

For a version of macOS that old, you’d probably want a dmg, which you can create with createinstallmedia if you have the Install macOS.app. Not sure if it’s supported with Lume as it’s the first time I’ve heard of it.

LoganDark | a month ago

Mojave never was an IPSW, because it never ran on Apple Silicon. I imagine this tool might just not support that at all.

[OP] frabonacci | a month ago

LoganDark is right. I've personally never tried, and don't think it'd be easy for any macOS predating Apple Virtualization Framework. For that you'd need something like UTM since they're relying on QEMU - these configs might help: https://github.com/adespoton/utmconfigs

cmckn | a month ago

Ahh I see. UTM was what I was trying, so I’ll give those a look! Thanks

illithid0 | a month ago

I was trying to do something similar last year and gave up because it felt futile. That said, it was the push I needed to try Rockbox, and I haven't looked back. Managing things via the file system is really nice.

cmckn | a month ago

I started on my Linux box and despite many apps claiming to support iPods, none would actually work. I ended up getting an old Mac mini running again and I’m using that for now. I’ve never given Rockbox a good look, I should check it out.

CharlesW | a month ago

I like to use MIST (macOS Installer Super Tool) to grab old macOS versions: https://github.com/ninxsoft/Mist

Apple also provides instructions for downloading many older macOS versions via your terminal: https://support.apple.com/en-us/102662#terminal

[OP] frabonacci | a month ago

Nice, thanks for sharing! It'd be interesting to integrate MIST into lume's ipsw command - right now Apple's native features in Apple Vz only provides download links for the latest supported version of the host, so grabbing older versions requires workarounds like this.

ahmadyan | a month ago

I believe this is using Virtualization.framework and not Containerization API from Tahoe, right?

Is there a limit on number of instances you can have per physical mac? i recall there was a hard limit of 2 because of EULA, unless Apple has changed it. (Cupertino really likes to sell you their Macs)

[OP] frabonacci | a month ago

Correct, Containerization APIs are Linux VMs specific.

There's a kernel-level check in the Hypervisor framework that enforces the 2 VM limit, and bypassing it violates Apple's EULA.

Nice technical deep-dive on the how here: https://khronokernel.com/macos/2023/08/08/AS-VM.html

eptcyka | a month ago

How is the networking? Tart broke networking in Tahoe. Would love to see this work, setting up base images has always been a massive pain.

[OP] frabonacci | a month ago

We haven't observed any networking degradation with Lume on Tahoe so far - things have been working smoothly in our testing. Give it a try and let us know if you run into any issues!

fkorotkov | a month ago

Can you elaborate on what got “broken” on Tahoe?

abrookewood | a month ago

"We built a VNC + OCR system that clicks through macOS Setup Assistant automatically" - that is both awesome and annoying. I guess I assumed that Apple supported some form of unattended setup.

[OP] frabonacci | a month ago

Yeah, Apple intentionally provides no unattended setup. Plus any process trying to control the UI programmatically needs explicit accessibility permissions, which defeats the purpose.

So we just click through like a human would via VNC. Version-specific but works with their security model rather than against it.

fartfeatures | a month ago

How does this compare to something like Tart and shapehq/tartelet

[OP] frabonacci | a month ago

Both use Apple's Virtualization Framework, so core VM performance is similar. Main differences are around agent-first design (HTTP API, MCP server), unattended setup via VNC + OCR, and registry support for VM images.

We've also built a broader ecosystem on top - the Cua computer and agent framework for building computer-use agents: https://cua.ai/docs

We went through the comparison with Tart, Lima etc here: https://github.com/trycua/cua/issues/10

fartfeatures | a month ago

Thanks for answering, makes sense.

Not seeing any reference to Tart at that link. Tart also has registry support for VM images it treats them very much like Docker images, is that what you are doing too?

Is it worth putting a comparison up somewhere other than a Github thread? Seems to be a frequently asked question at this point.

Also worth drawing attention to Tart being source available not open source.

[OP] frabonacci | a month ago

Thanks for the feedback! You're right that a proper comparison page beats hunting through GitHub issues.

We just put one together (with some help from Claude Code, naturally): https://cua.ai/docs/lume/guide/getting-started/comparison

fartfeatures | a month ago

Thanks much appreciated, the "Registry Support" section is weird though. Isn't GHCR an instance of an OCI registry? The when to choose Loom in the Tart section should also mention licensing, it is relevant at the choosing point.

[OP] frabonacci | a month ago

Good catches, thanks! Just updated the page:

Fixed the registry description—you're right, GHCR is an OCI registry. Both tools use OCI-compatible registries, we just default to GHCR/GCS.

Added licensing to the "when to choose" sections.

fartfeatures | a month ago

Good changes, like the new theme too, I'd still match the two boxes if it were me (both should read OCI registry and optionally include GHCR but they should be identical)

torarnv | a month ago

> Lume automates the macOS Setup Assistant via VNC and OCR, creating ready-to-use VMs without manual clicking. Tart relies on Packer plugins for automation.

This feels disingenuous. Tart has unattended setup support as well, and it's based on the same VNC + OCR technique as Lume. In fact Tart had it first, and your approach seems to be heavily inspired by it. In addition the boot command instructions you're using came from https://github.com/cirruslabs/macos-image-templates/

The only material difference is whether it's built-in or integrated via Packer.

JSR_FDED | a month ago

Looked at Lume before and it was already very impressive then. For this unattended use case this looks amazing.

Slight tangent - do the VMs have decent graphics performance? I live in fear of one day accidentally pressing the Update button and being forced into the GUI mess that is Tahoe. Knowing I could just use a VM with Sequioa as my primary desktop would dramatically lower my anxiety.

[OP] frabonacci | a month ago

Thanks! On graphics - currently it's paravirtualized via Apple's Virtualization Framework, so basic 2D acceleration but no GPU passthrough. Fine for desktop use, web browsing, coding, productivity apps. Wouldn't recommend it for anything GPU-intensive though.

Good news is there are hints of GPU passthrough coming (_VZPCIDeviceConfiguration symbol appeared in Tahoe's Virtualization framework), so that might land in a future macOS release. We're keeping an eye on it.

JimDabell | a month ago

> We built a VNC + OCR system that clicks through macOS Setup Assistant automatically.

You can automate at least some of this with `defaults write` commands or copying files to the right places. If you look at what some existing MDM platforms do you should be able to do this a lot more efficiently.

[OP] frabonacci | a month ago

MDM platforms can skip Setup Assistant, but they require the device to be pre-enrolled in Apple Business Manager before first boot - VMs can't be enrolled in ABM, so those hooks aren't available.

defaults write only works after you have shell access, which means Setup Assistant is already done.

There are tools that modify marker files like .AppleSetupDone via Recovery Mode, but that's mainly for bypassing MDM enrollment on physical Macs - you'd still need to create a valid user account with proper Directory Services entries, keychain, etc.

The VNC + OCR approach is less elegant but works reliably without needing to reverse-engineer macOS internals or rely on undocumented behaviors that might break between versions.

saagarjha | a month ago

Surely your VNC script is guaranteed to break between versions

pjmlp | a month ago

This at least feels more natural than writing Swift scripts.