A computer that isn’t tied to a device.
Runs on a server
Your programs, files and sign-ins live on a small Linux machine in the cloud. It stays on when you close the lid.
Drawn on your laptop
Every frame is drawn by your own GPU instead of arriving as video. The paint on this box is being drawn by yours right now.
Spacebox is a Linux computer that runs on a server and opens on your laptop as a window. It is early: today it runs in our lab, on one MacBook and one server.
It sends what to draw, not a video of it.
Most remote desktops draw the screen on the server and send you pictures of it. Spacebox splits the computer’s virtual GPU in two. The half on the server collects the drawing commands your programs make. The half on your laptop carries them out on a real GPU, so the server needs no GPU at all.
- server → laptop Drawing commands About 2 MB a second while a page scrolls, before compression.
- server → laptop Video, still compressed The server never decodes it. Your laptop’s hardware decoder does, from about 3 MB a second at 1080p60.
- server → laptop Sound Played by your laptop.
- laptop → server Keys, pointer and scroll The only things your laptop sends back.
Measured in our trial
| What you do | What reaches your screen | What it costs the server |
|---|---|---|
| Scroll a web page | 119 new frames a second on a 120 Hz display | 28% of one CPU core |
| Play 1080p60 video | 58 frames a second | 24% of one CPU core |
| Type | Each character in its own frame, at 10 characters a second | 11% of one CPU core |
Measured on 6 October 2026. The computer was Debian 13 with GNOME and Chromium, given one virtual CPU and 4 GB of memory on an AWS server in Seoul that has no GPU. The laptop was a MacBook Pro (M1 Max, 120 Hz display) on 2.4 GHz Wi-Fi, with a 5 ms round trip to the server. Frames were counted as they were handed to the Mac’s window.
These are light workloads. Pages that keep the one CPU fully busy still stutter, and that is what we are working on now.
Where it is today
Spacebox is early. It runs in our lab, and there is nothing to install yet.
Works in the trial
- A Linux desktop in a window on the Mac, sharp at 2x scale
- Scrolling at the display’s full 120 Hz
- 1080p60 video, decoded by the Mac’s own hardware (VP9 and H.264)
- Carrying on after the network drops, without a restart
Still ahead
- Moving a running computer between your laptop and the server
- Staying signed in to your sites wherever it runs
- Heavy pages on a small share of a server
- A build you can install
Built on QEMU
Spacebox is built on QEMU and virglrenderer. Our changes to QEMU are public, kept as commits on top of QEMU’s own history.