ianseyler

Potentially! It really depends on building it to run on BareMetal.

Can you try it again? I see some valid logins via Google.

None yet - this is a beta so bandwidth pricing will come later.

I’m glad you remember it! I’ve been plugging away at it for quite some time now.

The kernel is mainly the same - just modifications for running under Firecracker.

It’s good to see this! I’m offering a cloud service to host unikernels based on my BareMetal kernel.

~$0.005 CAD/h for a small network-enabled VM with 4MiB of RAM and no disk.

https://baremetal.returninfinity.com

We built BareMetal OS - a minimal exokernel with sub-millisecond cold boot and hardware level microVM isolation. We think it's small (VMs can use as little as 4MiB of RAM) and fast enough to be genuinely interesting to build on. So we're running a 2-week challenge to find out what you can build. See link for contest details and rules. Complimentary cloud credits for every applicant to help you build on our servers. Grand prize winner announced Sep 24, 2026.

I’d be interested in attempting to run this in a network- enabled 32MiB RAM microVM.

BareMetal is an x86-64 exokernel written entirely in hand-coded Assembly. This repo adapts it to run natively inside Firecracker microVMs. No BIOS, no UEFI, no PCI bus - just virtio-net and virtio-block over MMIO.

~800µs cold start in Firecracker on an AMD Ryzen AI Max+ 395. ~600µs with only networking.

Each microVM can be provisioned with as little as 2MiB of RAM. The kernel binary itself is ~5.5KB - the rest of the kernel image is layout padding to place the monitor and application payloads at fixed memory addresses.

A simple web server with some static content to server.

Can we get smaller VM hosts? I’ve seen some minimums at 512MB for a host. I need 8MB at most sometimes.

Update: Fourplex (this host) uses a 1GB minimum.

Newlib has been ported: https://github.com/ReturnInfinity/BareMetal-newlib4

The plan is to get existing *nix programs ported over, yes. That will require some more work (ideally a compatibility layer/library).

Working on that now ;)

Correct. BareMetal (the kernel) doesn't have context switching or userland. Think of the kernel as just a hardware abstraction layer.

It’s always fun to see this get brought up on Hacker News! I’m the developer behind BareMetal OS.

Keep in mind that this is all geared toward raw compute and throughput. No ring-3, no multitasking (we do support multiple cores though), and no higher-level abstractions like TCP/IP or full-featured file systems.

While it’s all coded in X86-64 assembly, a rewrite to ARM/RISC-V would be interesting once that hardware is standardized.

Keyboard is supported. NVMe, AHCI, ATA, and VirtIO for storage. A few gigabit network adapters from Intel, Realtek, and also VirtIO. A 10gbit intel network driver is currently being developed. Send works on it currently.

Interesting to see it written in higher-level languages!

Good point! I've added some text about wozmon to the README.

Yes - it uses the BareMetal OS kernel. I also wrote that.

That was the primary reason - a fun weekend project converting 6502 Assembly to x86-64 line by line. The x86-64 version comes in at a 384-byte binary due to instructions being a bit longer.

Agreed. Not sure what the status of the company is either. Their GitHub repos have been quiet for years.

Kano - https://kano.tech/us/original

Looks like their website has changed around. They used to have a kit that came with a raspberry pi (that you had to assemble yourself) and their own Linux-based OS that taught you about computers and the command line

https://github.com/KanoComputing/kano-desktop https://www.tomshardware.com/reviews/kano-computer-kit-touch...