18 / LaboratorySheet 00 · Index · Rev A

osu! tooling, engineered and measured.

We build the daemon that reads the game, the tools that put its live data to work, and the overlay manager that draws inside it. Native Rust, Linux first-class, and every performance claim published with its method.

01Get vosu→ 02Get vosulay→ 03Get tools→
FIG.01 Mark · construction Ø 464 ref · 3° graduations
Cursor
X 0000 · Y 0000
Local
--:--:--
Builds
vosu 1.2.0 · vosulay 1.5.0
Targets
osu!stable · osu!lazer
Status
Nominal
Sheet 01Route18-LAB / IDX / 001

Live data,
put to work.

vosu reads osu! as you play and hands that live state to everything around it: overlays on stream, vosulay in game, and tools that work with the map you have selected. Preview it live with your skin, see its pp on other servers, make practice maps at new rates, rate mania charts section by section, render replays. Select a stage to open its dossier.

Sheet 02Measurevosu 1.2.0 · 1.1.0 / tosu 4.26.2

Measured,
not claimed.

Less of your PC goes to reading the game and more to playing it. On live osu! clients, vosu used about a third of tosu’s memory on Windows, under a sixth on Linux, and less CPU in every run. The narrowest margin is listed alongside the widest.

FIG.02 Reading one game update · µs · lower is better tosu 4.26.2vosu

Source: vosu benchmark guide, released tosu comparison. Windows stable: vosu 1.2.0, 2026-10-25. Linux: vosu 1.1.0, 2026-10-17, retained for 1.2.0. One 25-minute map in Autoplay, matched settings; memory and CPU with both programs running. Windows lazer was not measured for 1.2.0. Conditions and full tables.

Sheet 03CapabilityWhat you can do

Your overlays,
and then some.

Switching from tosu keeps the overlays you already use. Here is what else vosu does with your game.

  1. C-01

    Your overlays, unchanged

    Overlays made for tosu, gosumemory or StreamCompanion keep working at the same address, and the dashboard installs more from the tosu community catalog.

    Compatibility

  2. C-02

    stable and lazer

    Reads osu!stable and osu!lazer on Windows, and osu!lazer natively on Linux. osu!stable through Wine is supported experimentally.

    WindowsLinux

  3. C-03

    In game, on Linux too

    vosulay draws your overlays inside osu! on Windows and Linux: Vulkan or OpenGL, Wayland or X11, and osu!stable under Wine. Move, resize and rotate them, and let layouts switch with the ruleset.

    vosulayWindowsLinux

  4. C-04

    Tools on the live game

    One click each from the dashboard: practice maps at new rates, a live map preview with your skin, server pp for the selected map, mania ratings, replay rendering, a skin studio, a beatmap downloader and your lazer library.

    vosu-tools

  5. C-05

    Settings profiles

    Keep different settings for the same overlay, one for stream and one for practice, and pin a browser source to the profile it needs.

    Overlays

  6. C-06

    Short overlay URLs

    Give an overlay a nickname and a short URL such as /acc/ to paste into OBS.

    Overlays

  7. C-07

    Across your network

    Share overlays with another PC on your LAN or Tailscale while settings stay on this one. vosulay can serve view-only layouts to browsers and streaming clients on your network.

    LANTailscale

  8. C-08

    Updates itself, safely

    Installs new releases at startup, checks each download against its published SHA-256, and can roll back a failed update. Linux packages update by installing the newer package.

    Updates

Sheet 04Comparevosu 1.2.0 / tosu 4.26.3

Side by side,
limits included.

tosu is the project vosu stays compatible with. Every tosu entry is checked against tosu’s own repository at v4.26.3; the memory figures come from 18-LAB’s measured comparison against tosu 4.26.2. Where vosu falls short, it says so.

Capabilityvosutosu
In-game overlay Linux and Windows, with vosulay Windows only1
Linux osu!lazer natively; osu!stable through Wine, experimental Linux build; stable tested with osu-winello, lazer with AppImage and Flatpak23
osu!stable and osu!lazer Both Both2
Existing overlays tosu, gosumemory and StreamCompanion overlays gosumemory and StreamCompanion compatible, plus its own API2
Tools Installs and runs them: practice, map preview, server pp and more Not among its listed features2
Memory while playing 48 MiB Windows stable · 30 MB Linux lazer 143 MiB · 266 MBM
Automatic updates Yes, SHA-256-checked with rollback Yes4
Signed Windows downloads No: SmartScreen may warn Yes, through SignPath2
macOS No No macOS build3
  1. 1tosu v4.26.3 · in-game overlay: “only available on the Windows platform”
  2. 2tosu v4.26.3 · README: features, Linux notice, code signing
  3. 3tosu v4.26.3 · release downloads: Linux and Windows
  4. 4tosu v4.26.3 · ENABLE_AUTOUPDATE setting
  5. Mvosu benchmark guide · daemon memory against tosu 4.26.2, both running

Where vosu stops

  • L-01Windows downloads are not code-signed yet, so SmartScreen may warn before the first launch.
  • L-02Live osu!lazer on Windows was not tested for 1.2.0: lazer would not start on the test machine. Its support passed tests against recorded game memory; reading a running lazer, lazer skins, the tools’ lazer features and vosulay in lazer were verified on Linux only.
  • L-03osu!stable on Linux runs through Wine and is experimental, not release-verified.
  • L-04Tools are not sandboxed: they run with your account’s permissions. Official tools are trusted; others wait for your approval on the dashboard.
  • L-05In-game overlays come from vosulay, installed as a tool or on its own; vosu itself draws nothing in game.
Sheet 05StartLinux · Windows · open source

Running in
three steps.

Free and open source. Your existing overlays come along.

  1. S-01

    Install vosu

    A portable ZIP for Windows or Linux, or a .deb, .rpm or Arch package. It opens its dashboard when it starts.

    Get vosu→ Releases→

  2. S-02

    Add tools

    Open Tools in the dashboard and install the ones you want, one click each.

    Browse vosu-tools→ Tools guide→

  3. S-03

    Put it in game

    Install vosulay from the same Tools page, or download it as a standalone app.

    Get vosulay→

Building overlays or tools? Developer docs · Overlay tutorial · Create a tool