Cinder

A fullscreen macOS terminal music visualizer in Go using Bubble Tea + Lip Gloss.

It polls Apple Music and Spotify via osascript every second, detects track + artist + playback state, and renders a live nebula-style particle field with song-derived colors. If nowplaying-cli is installed, Cinder uses it first for more reliable now-playing detection and falls back to AppleScript automatically. For true audio-reactive motion, Cinder can also analyze a live AVFoundation audio input via ffmpeg.

Features

• Fullscreen terminal rendering with Bubble Tea AltScreen
• Cursor hidden for an immersive display
• Polling now-playing metadata from Apple Music and Spotify
• 260-particle physics system with:
  • velocity + damping
  • lifespan/decay
  • orbital drift and turbulence
  • dense glowing core
• Song-change explosion from center
• Optional live audio-reactive input with onset, bass/treble energy, and rolling BPM estimation
• Per-song motion profiles that change pace, trail length, orbit count, and pulse sharpness
• Tempo-shaped synthetic rhythm layers: fast tracks feel tighter and faster, slower tracks drift and breathe more
• Cleaner trippy ribbon fields with stronger section shifts and less muddy overlap
• Pause handling: particles gradually decelerate and freeze
• Resume handling: particles reignite and expand again
• Per-song color palettes hashed from title
• No chrome UI; only particles + dim now-playing text in bottom-left

Project Structure

• nowplaying/ — AppleScript polling and metadata parsing
• visualizer/ — particle simulation and frame rendering
• ui/ — Bubble Tea model, update loop, and terminal composition
• config/ — palette generation and color utilities

Install

brew tap moKshagna-p/cinder
brew install cinder-tui

Then just run:

cinder

If BlackHole is installed and available, cinder will automatically use it for the audio-reactive version. If you want the original non-audio-reactive view, run:

cinder --normal

Homebrew installs a prebuilt macOS binary from the tap, so end users do not need Go installed.

If you prefer a single command without tapping first:

brew install moKshagna-p/cinder/cinder-tui

Optional enhancements after install:

# One-time audio-reactive setup
cinder --setup-audio
cinder --doctor
cinder

# Richer now-playing metadata
brew install nowplaying-cli
cinder

ffmpeg is installed automatically with cinder-tui. For full system-audio reactivity, users only need to install and configure BlackHole 2ch once. After that, plain cinder will automatically launch the BlackHole-driven version when it is available.

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Requirements (manual build)

• macOS
• Go 1.22+
• Apple Music and/or Spotify installed (optional but required for metadata)
• nowplaying-cli (optional, recommended for better media session detection)
• ffmpeg (required for live audio-reactive input, installed automatically by Homebrew)
• A loopback input such as BlackHole (optional, recommended if you want system-output reactivity instead of microphone reactivity)

Run

make tidy
make run

After BlackHole is configured once, plain cinder will launch the audio-reactive version automatically:

go run .

Force the original non-audio-reactive view:

go run . --normal

Use a specific AVFoundation audio input device explicitly:

go run . --audio-device "BlackHole 2ch"

List available audio devices:

go run . --list-audio-devices

Check whether ffmpeg, loopback inputs, and metadata helpers are available:

go run . --doctor

If nowplaying-cli is installed but not compatible with your macOS version, force AppleScript backend:

CINDER_NOWPLAYING_BACKEND=applescript make run

If you want the visuals to follow the actual music output, route your player audio into a loopback input. When Cinder sees a preferred loopback device such as BlackHole 2ch, it will automatically choose the audio-reactive version on startup.

Controls:

• q, esc, or ctrl+c to quit
• m to cycle animation modes (Nebula → Waveform → Spectrum → Vortex → Pulse)

Build

make build
./bin/cinder