Loading...
Open SourceMac App for Calm & SleepNigeria
Hush
Hush is our open-source macOS app for calm and sleep. It plays pure tones, binaural and isochronic beats, seven colours of noise and five nature sounds, all synthesized live on the audio thread, so nothing loops and it can play cleanly all night. It has no dependencies, needs no network connection and collects no data. We also ported its sound engine to Rust as hush-core, with a CLI and a WebAssembly demo.
SwiftSwiftUIAVAudioEngineRustOpen Source
Headline
Open source, plus a Rust port with a browser demo
01 The brief
What they needed.
Most sleep apps loop short recordings, which the ear learns to hear, and real-time audio can crackle, drop out or drift over a long night. Hush had to generate every sound live, stay glitch-free for hours, and never stop abruptly.
02 Our approach
How we built it.
Built with Swift, SwiftUI and AVAudioEngine. Nothing on the audio thread allocates or locks; the UI writes settings into atomics that the render callback only reads.
Every gain change ramps, isochronic pulses use raised-cosine edges, and output is soft-clipped instead of hard-clamped, so the sound never clicks.
Sleep journeys step the pulse rate down in stages, the timer fades over the final stretch, and the engine rebuilds seamlessly when headphones are plugged in.
The engine was ported to Rust as hush-core: a library, a terminal player for macOS, Linux and Windows, and a browser demo running in an AudioWorklet.
03 Outcomes
What shipped.
Concrete results, not promises. Each line is something that exists and works today.
Open source on GitHub, with a Rust port and live browser demo
No dependencies, no network connection, no data collected
Every sound synthesized live, so nothing loops
04 Stack
SwiftSwiftUIAVAudioEngineRustOpen Source
Like what you see?
We build every project
like it's our own.
Same process, same attention to detail, applied to your idea. Tell us what you need and we will show you what is possible.