Questions, answered.

An immutable, CachyOS-based operating system that turns a PC with an AMD GPU into a headless Steam streaming box. Steam runs on a virtual display on the PC, Sunshine streams it, and you play with Moonlight on a TV, phone, tablet or laptop. You install and manage it from a web page on your phone.

Not yet. VaporOS streams with AMD Radeon GPUs on the amdgpu driver. On other graphics it still installs and runs, but the control center's Home and the welcome screen say there's no supported graphics card, and it won't stream. Very old AMD cards that use the legacy radeon driver aren't supported either.

Not even to install, if the PC already boots from the USB stick in UEFI mode with Secure Boot off: with no monitor connected, the installer skips the setup code. A monitor or TV makes the firmware settings and the code easy.

After that you don't need one. VaporOS makes its own virtual display at the resolution, frame rate and HDR setting of the device you stream to, so you don't need a dummy plug either.

If a monitor is connected, it only ever shows the welcome screen: the address of the PC, a QR code, and a status line such as “Ready to stream”. It never shows a terminal or a desktop.

Yes, if the PC already boots from the USB stick in UEFI mode with Secure Boot off. With no monitor connected, the installer doesn't ask for the setup code: open http://vaporos-setup.local on your phone. Anyone on your network could open it while it waits, so do this on a network you trust.

If the PC's graphics card isn't recognised yet, the installer still asks for the code, which a monitor shows.

Drives formatted ext2, ext3, ext4, btrfs, XFS, F2FS or NTFS. exFAT and FAT drives can't be used for games. VaporOS mounts the drive, adds it to Steam's library list, and never changes the files on it; a drive without a library gets an empty SteamLibrary folder.

No. VaporOS installs to a whole drive and erases it. Other drives in the PC are left alone, and if they hold Steam libraries you can pick them during setup (or later, under System › Storage) and keep playing those games. Nothing on them is changed.

The VaporOS kernel isn't signed for Secure Boot, so firmware with Secure Boot on refuses to start it. Turn Secure Boot off and boot in UEFI mode. Legacy (CSM/BIOS) boot isn't supported.

After installing, open http://vapor.local on a phone or computer on the same network. If you picked another name during setup, it's that name plus .local. A connected monitor also shows the address, the PC's IP address and a QR code. With no monitor, your router's list of devices shows its IP address.

While you install from the USB stick, the address is http://vaporos-setup.local.

From this project's GitHub container registry, ghcr.io/jasperaelvoet/vaporos. By default VaporOS downloads new versions in the background and prepares them; they start on the next restart. You can turn that off and update by hand under System › Updates.

Every update has to carry a valid ed25519 signature from the release key, before VaporOS writes anything, and every file has to match its size and SHA-256 before the new version can start. The main channel is the stable one; other channels are test builds.

VaporOS keeps two copies of the system. An update goes to the one you aren't running, and the old one stays as it was. If the new version doesn't start cleanly, the PC goes back to the previous version by itself and won't install that version again.

You can also go back by hand: open System › Updates, choose Go back, and restart. VaporOS then holds back the version you left: it won't install it again by itself, only a newer one.

Every release comes with SHA256SUMS and a signed manifest.json. The download page shows how to check both. They prove different things: SHA256SUMS catches a damaged download, and the signature proves that manifest.json, the list of system image files, came from the release key. Neither signs the ISO file itself, because SHA256SUMS is not signed.

The installer on the ISO only installs a system image whose manifest carries a valid signature. Download from this site or the project's GitHub releases.

The web page only answers devices on private networks, such as your home network, and asks for your admin password. Sunshine's own admin page is never reachable from other devices. SSH is off unless you turn it on under System › Settings, and then only with keys you add.

Not with a package manager. The system is one read-only image, which is what makes updates and rollback reliable. Games come from Steam, as usual.

VaporOS has a few extensions it builds and checks itself: CachyOS Proton, which is always on, and CoolerControl, TruckersMP and the Star Citizen launcher, which you add under System › Extensions. Each one is a sealed, read-only package that updates and rolls back together with VaporOS.

It depends on the PC. When a wired network adapter can wake it from Moonlight (Wake-on-LAN), the installer turns on idle power-off: after 15 minutes of nobody playing it powers off, but never while it streams, runs a game, downloads or updates. Otherwise it stays on. You can change this, or keep it awake for 1 or 4 hours, under System › Power.

Yes, when the PC is on a network cable and Wake-on-LAN works. In Moonlight, pick the PC and choose Wake; this works for a PC Moonlight has paired with.

Any Wake-on-LAN app on the same network works too, with the MAC address and the broadcast address on the Wake it card under System › Power. Save them while the PC is on.

The VaporOS web page itself can't wake the PC: the PC serves that page, and a web page can't send the wake packet. If the PC goes to sleep while the page is open, the page says how to wake it and reconnects by itself once it's back.

The resolution, refresh rate and HDR are set when a game starts in Moonlight. Resuming it from another device keeps them. Quit the game in Moonlight first, then start it on the new device.

Not from the web page: the installer and the control center only set up a network cable, and Wake-on-LAN needs the cable.