devalang 0.1.4

Write music like code. Devalang is a domain-specific language (DSL) for sound designers and music hackers. Compose, automate, and control sound — in plain text.
Documentation

Rust TypeScript Node.js

Project Status Version License: MIT

Linux macOS Windows

npm crates

🦊 Devalang — Write music with code

Devalang is a compact domain-specific language (DSL) for music makers, sound designers, and creative coders. Compose loops, control samples, synthesize audio, and render your ideas — all in clean, readable text.

Whether you're prototyping a beat, building generative music, or performing live, Devalang gives you rhythmic precision with the elegance of code.

From studio sketches to live sets, Devalang puts musical ideas into motion.

🚀 v0.1.0+ - Complete Rewriting

NEW: Devalang Playground V2.0 is now available — Try it in your browser!

📚 Quick Access

Websites & Resources

Important files

Common projects and tools

Downloads

⚡ Quick Start

Try in Your Browser

Launch the Playground to try Devalang without installing anything.

Download the Installers (Recommended)

Visit the Download page to get the latest releases for Windows, macOS, and Linux.

Install via npm (Node.js)

npm install -g @devaloop/devalang

Install via Cargo (Rust)

cargo install devalang

Create Your First Project

# Initialize a new project

devalang init my-project


# Navigate to the project

cd my-project


# Check syntax

devalang check --entry examples/index.deva


# Build audio files

devalang build --path examples/index.deva --formats wav mid


# Play audio (live mode)

devalang play --live --input examples/index.deva

📦 (optional) Install addons

Devalang supports addons to extend functionalities. This allows you to easily add sound banks, effects, or other features.

To create your own addon, please refer to the Devapack documentation.

# List available addons

devalang addon list


# Install an addon (format: <author>.<addon-name>)

devalang addon install devaloop.808

This will install the devaloop.808 sound bank in your current working directory inside .deva folder.

You can then use it in your Devalang scripts !

🎵 Your First Devalang File

Create a file hello.deva or index.deva (if you do not specify --input argument, it defaults to index.deva).

Nomenclature for .deva files

  • Devalang files use the .deva extension.
  • Devalang engine is indentation-sensitive for blocks, similar to Python.
  • Files are plain text and can be edited with any text editor (VSCode recommended).
  • Ensure your text editor supports UTF-8 encoding.
  • Devalang is case-sensitive, so be consistent with capitalization.
  • Devalang reads files from top to bottom, so order matters.
  • Devalang files typically start with global settings (e.g., bpm, bank), followed by definitions (synth, pattern, group), and finally execution commands (spawn, play).
  • Devalang files can include comments using # or // for single-line comments.
  • You can name your files anything, but index.deva is a common convention for the main entry file.
  • You can organize your project with subfolders as needed. (use module system like @import { var } from '<module_path>' and @export { var }).

Refer to the documentation for a complete syntax reference.

# Set the tempo
bpm 120

# Load a bank of sounds (make sure you have the bank installed)
bank devaloop.808 as drums

# Create a simple kick pattern
pattern kickPattern with drums.kick = "x--- x--- x--- x---"

# Define a synth and a melody
let mySynth = synth saw

# Define a melody using a group to organize notes
group myMelody:

  mySynth -> note(C5)
      -> duration(500)           # 500ms

  mySynth -> note(E5)
      -> duration(1/4)           # Quarter note

  mySynth -> note(G5)
      -> duration(1/16)           # Sixteenth note
      -> velocity(0.8)            # Velocity (0.0 to 1.0) or 0-127
      -> lpf(800)                 # Lowpass filter at 800Hz
      -> reverb({ size: 0.3 })    # Reverb effect

# Play the melody (in parallel)
spawn myMelody

# Play the kick pattern (in parallel too)
spawn kickPattern

(optional) Configure project settings

You can create a devalang.json (recommended) or devalang.toml or even .devalang (legacy) file to customize check/build/play settings.

This typically evitate to re-type common arguments like --path, --formats, etc.

Comments are not supported in config files, please use devalang init to generate a default config.

{
  "project": {
    "name": "My Awesome Project"        // Change this to adjust project name
  },
  "paths": {
    "entry": "audio/helloWorld.deva",   // Change this to adjust entry file path
    "output": "output"                  // Change this to adjust output directory
  },
  "audio": {
    "format": ["wav", "mid"],           // Change this to adjust output formats (options: wav, mid, mp3)
    "bit_depth": 16,                    // Change this to 24 or 32 for higher quality
    "channels": 2,                      // Change this to 1 for mono output
    "sample_rate": 44100,               // Change this to 48000 for higher quality
    "resample_quality": "sinc24",       // Change this to adjust resampling quality (options: sinc8, sinc16, sinc24, sinc32)
    "bpm": 120                           // Change this to adjust the project tempo (only if not set in code)
  },
  "live": {
    "crossfade_ms": 500                  // Change this to adjust crossfade duration when playing live
  }
}

Build the audio

# Build to WAV, MP3, and MIDI

devalang build --path hello.deva --formats wav,mp3,mid

Play the audio

# Play the audio file

devalang play --input hello.deva


# Play live (repeats and watch until stopped)

devalang play --live --input hello.deva


# Play live loop with very short crossfade

# With 50ms, transitions between loops are no more distinguishable

devalang play --live --crossfade-ms 50 --input hello.deva

🚀 Features

🎵 Core Language

  • ✅ Lexer & Parser — Complete tokenization and AST generation
  • ✅ Patterns — Rhythmic notation with swing, humanize, velocity
  • ✅ Synths — Built-in synthesizers with ADSR envelopes
  • ✅ Filters — Lowpass, highpass, bandpass audio filtering
  • ✅ Effects — Reverb, delay, distortion, drive, chorus
  • ✅ Variables — let, const, var with scoping
  • ✅ Groups & Spawn — Organize and parallelize execution
  • ✅ Loops & Conditions — for, if, else control flow
  • ✅ Triggers — Conditional audio triggering
  • ✅ Events — Event system with on and emit

🛠️ CLI Tools

  • ✅ devalang init — Scaffold new projects (3 templates)
  • ✅ devalang build — Compile to WAV/MIDI
  • ✅ devalang check — Validate syntax
  • ✅ devalang play — Audio playback
  • ✅ devalang addon — Manage addons (install, list, discover)
  • ✅ devalang login/logout — Authentication
  • ✅ devalang telemetry — Privacy controls

🌐 WASM API

  • ✅ render_audio() — Browser audio rendering
  • ✅ render_midi_array() — MIDI export
  • ✅ debug_render() — Debug information
  • ✅ parse() — Parse Devalang code
  • ✅ TypeScript types included

📦 Output Formats

  • ✅ WAV — 16/24/32-bit audio export
  • ✅ MIDI — Standard MIDI file export
  • ✅ MP3 — Lossy audio export (via LAME)

🎯 Performance

  • ⚡ Fast builds — 7-10ms for typical projects
  • ⚡ Low latency — Optimized audio engine
  • ⚡ Release builds — 5-6x faster than debug

📚 Learning Resources

  • ✅ Online Docs — Complete language reference
  • ✅ VSCode Extension — Syntax highlighting

💡 Why Devalang?

  • 🎹 Prototype audio ideas without opening a DAW
  • 💻 Integrate sound into code-based workflows
  • 🎛️ Control audio parameters with readable syntax
  • 🧪 Build musical logic with variables and conditions
  • 🔄 Create patterns with expressive notation
  • 🎨 Live code with fast iteration cycles
  • 📦 Version control your music with git

📖 Documentation

Visit docs.devalang.com for:

  • Complete syntax reference
  • API documentation
  • WASM integration guide
  • CLI command reference
  • Advanced tutorials
  • Best practices

🔧 Development

Build from Source

# Clone the repository

git clone https://github.com/devaloop-labs/devalang.git

cd devalang


# NPM (TypeScript) and Cargo (Rust) are required

npm install


# Build CLI (Rust)

cargo build


# Build WASM (Web & Node.js)

npm run rust:wasm:all


# Build TypeScript

npm run ts:build


# Run tests

cargo test --features cli

npm test

🤝 Contributing

We welcome contributions! See CONTRIBUTING.md for guidelines.

Ways to Contribute

  • 🐛 Report bugs via GitHub Issues
  • 💡 Suggest features in discussions
  • 📝 Improve docs with pull requests
  • 🎵 Share examples of your creations
  • 🧪 Write tests for new features

📜 License

MIT License — See LICENSE for details.

Copyright (c) 2025 Devaloop