strudel-cli

A Node.js CLI for rendering Strudel patterns to chiptune audio. Play live or export to WAV.

Uses the real Strudel pattern engine (@strudel/core, @strudel/mini, @strudel/transpiler, @strudel/tonal) with a custom audio renderer built on node-web-audio-api (Rust-backed).

Install

git clone https://github.com/ryanfoxeth/strudel-cli.git
cd strudel-cli
npm install
npm link

Usage

# Play live
strudel-cli 'note("c4 e4 g4 c5")' --play
# Render to WAV
strudel-cli 'note("c4 e4 g4 c5")' -o output.wav
# Both
strudel-cli 'note("c4 e4 g4 c5")' --play -o output.wav

Options

Flag	Description	Default
-p, --play	Play in real time	off
-o, --output <file>	Output WAV file path	output.wav
-b, --bpm <n>	Beats per minute	120
-c, --cycles <n>	Number of cycles to render	4
-w, --wave <type>	Default waveform: square, triangle, sawtooth, sine	square
-s, --sample-rate <n>	Sample rate	44100

Per-voice waveforms

Use .s() to set waveform per voice:

strudel-cli 'stack( note("c2 g2 ab2 bb2").s("sawtooth").gain(0.2), note("c4 eb4 g4 c5").gain(0.25), note("g5 eb5 g5 c5").fast(2).s("triangle").gain(0.1))' --play -b 140

Strudel pattern language

Full Strudel pattern language is supported: note(), stack(), cat(), fast(), slow(), mini notation, euclidean rhythms, and more. See Strudel docs.

Architecture

Strudel (upstream) strudel-cli (this repo)
┌─────────────────┐ ┌──────────────────────┐
│ Pattern engine │ ──→ │ Oscillator synth │
│ Mini notation │ │ ADSR envelopes │
│ Transpiler │ │ WAV encoder │
│ Music theory │ │ Real-time playback │
└─────────────────┘ └──────────────────────┘

The synth is intentionally simple — square, triangle, sawtooth, and sine oscillators with ADSR envelopes. Perfect for chiptune and video game music.

Requirements

• Node.js 18+

License

AGPL-3.0-or-later (same as Strudel)