Living GPU art for your idle screen. 11 curated scenes · 13 color styles · macOS + Windows · free & open source
Flux Drift — thousands of luminous blades riding a real Navier–Stokes fluid simulation, live on your GPU.
Noctura is a native screensaver for macOS (.saver) and Windows (.scr), plus a desktop gallery app — the same scenes everywhere, rendered by Metal, Direct3D 11, and WebGL at full parity. No Electron in your lock screen, no runtime to install, a few hundred kilobytes of native code. It adapts its resolution to your GPU, throttles itself on battery, and updates in place.
Grab the latest build from the Releases page.
| Platform | File | Notes |
|---|---|---|
| Windows (x64 + ARM64) | NocturaSetup.exe |
Real install wizard — auto-detects your CPU, registers in Apps & features, upgrades replace old versions |
| macOS screensaver | Noctura-<ver>.pkg |
Native installer — installs for all users and cleans up old copies automatically |
| macOS app (Intel + Apple Silicon) | Noctura_<ver>_universal.dmg |
Styled drag-to-Applications DMG; the app self-updates from GitHub Releases |
| macOS app (Apple Silicon only) | Noctura_<ver>_aarch64.dmg |
Smaller download for M-series Macs |
| Windows (zip, advanced) | Noctura-Windows.zip |
Raw .scr + install/uninstall scripts, if you prefer no installer |
Builds are unsigned (ad-hoc signed, no paid Developer ID), so the OS warns on first launch — you can still open them:
- macOS: drag Noctura to Applications, double-click, click Done on the warning, then System Settings → Privacy & Security → scroll to "Noctura was blocked" → Open Anyway. Guaranteed alternative:
xattr -dr com.apple.quarantine /Applications/Noctura.app.- Windows: SmartScreen → More info → Run anyway.
- Upgrades are clean by design:
NocturaSetup.exeand the.pkgreplace any previous version (including removing orphaned copies), and the macOS app offers one-click self-updates from this repo's releases. - Uninstall on Windows: Settings → Apps → Noctura → Uninstall.
- Uninstall the macOS screensaver: delete
/Library/Screen Savers/Noctura.saver(or~/Library/Screen Savers/Noctura.saverfor zip-era installs). - Uninstall the macOS app: drag
Noctura.appfrom Applications to the Trash.
11 curated scenes — Flux Drift · Northern Lights · Deep Space · Particle Drift · Plasma Field · Fireflies · Black Hole · Caustics · Nebula Drift · Fractal Bloom · Particle Swarm
Flux Drift is the flagship scene: a faithful port of Flux (sandydoo's open-source tribute to the macOS Drift screensaver), rebuilt from its source. A real GPU Stable-Fluids simulation (Jos Stam Navier–Stokes, 128² grid) runs at true 60 Hz; thousands of line "blades" — one per 15 logical pixels of your display — chase the fluid with damped-spring physics, and even their colors have inertia, smoothed by a second spring from the local flow velocity. Lines accumulate in linear color space with a final sRGB encode, exactly like the reference's rendering pipeline.
Each scene below is shown in a different one of the 13 color Styles, to hint at the range — every scene works with every palette.
Each scene is tunable: Style (13 palettes — Aurora, Borealis, Deep Space, Ocean, Ember, Synthwave, Sunset, Nebula, Mint, Gold, Ice, Rose, Monochrome), Speed, Intensity, Density, Size, and a Performance mode (Auto / Full / Balanced / Power Saver) that scales render resolution to stay smooth on any GPU.
All three builds can overlay the time (or time + date) on top of the scene — choose a typeface (Light · Modern · Bold · Mono, mapped to each OS's best modern system font), a position (Center · Top · Bottom · Corner), and 12- or 24-hour format.
Lock on resume: require sign-in when the screensaver ends. On Windows this is a one-click toggle in the saver's settings. On macOS it's an OS-owned setting a screensaver can't change itself — enable System Settings → Lock Screen → "Require password after screen saver begins" → Immediately and macOS locks automatically the moment the screensaver starts; the saver's Options sheet points you there.
| Build | Tech | What it is |
|---|---|---|
| Desktop app | Tauri 2 · React · WebGL | The full gallery: browse scenes, tune them live, slideshow, favorites, clock overlay — and signed in-place self-updates. |
macOS .saver |
Swift · Metal | A true system screensaver in System Settings → Screen Saver. See native-saver/. |
Windows .scr |
Rust · Direct3D 11 | A true Windows screensaver (/s /p /c) in a single ~400 KB binary, no runtime to install. See windows-saver/. |
The macOS Metal shader and the Windows HLSL shader are faithful ports of the same canonical scene shader, sharing an identical uniform layout — so all three platforms render the same image. Flux Drift goes further: all three renderers run the same multi-pass architecture ported from the Flux source — a 128² Navier-Stokes solver stepped at a fixed 60 Hz, a per-line state pass carrying 12 floats of spring physics per blade (endpoint, velocity, color, color-velocity, width) in MRT float textures, an endpoint pass with Flux's blend-compensation trick, and linear-space accumulation with an sRGB encode — so the fluid look and motion match across web, macOS, and Windows (verified against the live reference with side-by-side captures and motion-decorrelation measurement).
bun install
bun run tauri build # → src-tauri/target/release/bundle/macOS Universal:
rustup target add x86_64-apple-darwin
bun run tauri build --target universal-apple-darwincd native-saver
./build.sh --install # builds + installs into ~/Library/Screen Savers/Native on Windows:
cd windows-saver
cargo build --release --target x86_64-pc-windows-msvcOr cross-compile from macOS/Linux (no Windows box needed):
cargo install --locked cargo-xwin
rustup target add x86_64-pc-windows-msvc aarch64-pc-windows-msvc
cd windows-saver && ./build-cross.sh # → dist/windows/src/ Web gallery (React + WebGL scenes)
src-tauri/ Tauri desktop app shell (Rust)
native-saver/ macOS .saver (Swift + Metal)
windows-saver/ Windows .scr (Rust + Direct3D 11)
screenshots/ Scene captures
MIT — see LICENSE. Created by Andre Hall.