A collection of projects based around a WASM port of the Composer's Desktop Project - using the latest web and agentic-control technologies to bring a new lease of life to 40 year old software - (hopefully) making it more easily accessible and fun to use.

The main motivation is that offline audio processing tools like CDP are very interesting to control via natural language with LLMs. With a thin javascript orchestration layer and a virtual file system, the CDP can be very powerful for agentic sound design.

You can use cdp-wasm on the command line via node or compatible JavaScript runtime see the npm package on npm.js.

// install cdp-wasm globally
npm i -g cdp-wasm

// use the cdp modify program - speed mode 2 to transpose in.wav down 12 semitones
cdp modify speed 2 in.wav out.wav -12

This is much like using the original CDP (where you must cross-reference the docs to get the command correct)

Remembering all those arguments is challenging, and when multiple programs are involved CDP can be very laborious to use like this. Many people use a UI frontend instead.

In cdp-wasm the javascript layer adds a curated catalog on top of the CDP programs that surfaces subprograms of CDP as ready-to-use effects and generators — each with curated parameters, ranges and defaults — and hides the multi-step plumbing (pvoc round-trips, mixfile chains, channel conforming).

import { CDP, EFFECTS, applyEffect } from 'cdp-wasm';

const cdp = new CDP();
const effect = EFFECTS.find((e) => e.id === 'modify.speed');
const out = await applyEffect(cdp, effect, { semitones: -12 }, await readFile('in.wav'));
await writeFile('out.wav', out);

Agentic tools can also help here. You can use the agent-skills to control it from claude, codex etc.

If you prefer a UI, cdp-web is a web based frontend, which you can use in the browser. It's a Progressive Web App so you can also install it to your desktop or your home screen on mobile. The agent-skills should also be able to create cdp-web patches.

The same UI frontend is used in the audio plugin, and the DAW Extension.

This laborious work has largely been automated using agentic AI - so YMMV - there will be mistakes, bugs and sloppy bits. It's still WIP, being de-sloppified. Please submit issues if you find any.

For more info visit the main website.

Enjoy!

Oli Larkin, Berlin, 2026.