Cagire: Live Coding in Forth

Nice. When I saw some javascript live music arrangement experiments, I thought that forth is syntactically better for that task because of postfix notation - no need to select and execute parts, keywords could be self-adding/playing.

Cool, and I love the retro font. I had a Vic-20 (early 80s) and Commodore PET 2001 (1977) I am learning Odin, and I was going to try creating live coding environment with scripting in Forth and with the gui and rest in Odin, but for audio and graphics. I was inspired long ago by Paul Batchelor's Sporth and Tidal (now tidal cycles?). Forth is a great language. You can make an compiler/interpreter in a few days. John Earnest's ok.js is also cool. I like stack and array languages, so when I am not playing in J, I use Uiua. Uiua has the capability to do audio and graphics/animations and scratches my array/stack itch.

for FORTH like synthesis environment you will want to check out SAPF! (by James McCartney author of SuperCollider) https://github.com/lfnoise/sapf

This is a neat project and I don't think I'm aware of any sequencers that allow for arbitrary execution per-step (not that I am that deep into the space). The font choice for the website is really... interesting. I don't think I can recall ever feeling this dyslexic trying to read the copy here.

This is super cool. I've been thinking about doing something like this for awhile as a retirement project.

Very cool. Are you near Aspet ? I often hike with a friend who lives there. The Cagire is one of my favorite peaks of the Pyrénées.

Oh it seems like forth is a pretty good candidate for this. Like most of these things are a post processing steps

Neato... I'm glad stuff like this exists in the world. I'm gonna steal some ideas for my own project (Skred). Thanks!

Toffoli and Margolis's CAM-6 cellular automata machine board for the IBM-PC was programmed in FORTH. I made a simulator, and this video shows some of the original FORTH code that I saved, as well as my own compatible FORTH CA rule computer that le me run the rules from the book, which produced lookup table for the hardware, which the simulator is compatible with. I've since rewritten it in JavaScript. It's not live coding, but it has a live performance user interface (quite weird and hard to figure out, especially if you haven't read the book, but I demonstrate it in the video).

CAM6 Demo

https://www.youtube.com/watch?v=LyLMHxRNuck

Original FORTH code that drove the actual CAM-6 board:

tomt-cam-forth-scr.txt: https://donhopkins.com/home/code/tomt-cam-forth-scr.txt

tomt-users-forth-scr.txt: https://donhopkins.com/home/code/tomt-users-forth-scr.txt

My compatible CA compiler and glue to the simulator written in C:

cam.f.txt: https://donhopkins.com/home/code/cam.f.txt

compile.f.txt: https://donhopkins.com/home/code/compile.f.txt

An old version of the simulator written C, before I rewrote it in JavaScript:

https://github.com/SimHacker/micropolis/tree/master/Micropol...

The JavaScript CAM6 simulator:

CAM6.js: https://github.com/SimHacker/CAM6/blob/master/javascript/CAM...

Very cool. Are you near Aspet ? I often hike with a friend who lives there. The Cagire is one of my favorite peaks of the Pyrénées.

Neato... I'm glad stuff like this exists in the world. I'm gonna steal some ideas for my own project (Skred). Thanks!

CAM6 Demo

https://www.youtube.com/watch?v=LyLMHxRNuck

Original FORTH code that drove the actual CAM-6 board:

tomt-cam-forth-scr.txt: https://donhopkins.com/home/code/tomt-cam-forth-scr.txt

tomt-users-forth-scr.txt: https://donhopkins.com/home/code/tomt-users-forth-scr.txt

My compatible CA compiler and glue to the simulator written in C:

cam.f.txt: https://donhopkins.com/home/code/cam.f.txt

compile.f.txt: https://donhopkins.com/home/code/compile.f.txt

An old version of the simulator written C, before I rewrote it in JavaScript:

https://github.com/SimHacker/micropolis/tree/master/Micropol...

The JavaScript CAM6 simulator:

CAM6.js: https://github.com/SimHacker/CAM6/blob/master/javascript/CAM...

for FORTH like synthesis environment you will want to check out SAPF! (by James McCartney author of SuperCollider) https://github.com/lfnoise/sapf

Wow, I never saw this! I like APL/J/Uiua, so this is perfect. Uiua is both stack and array based. Thanks!

concatenative code is sort of a natural fit for audio in terms of representing signal flow...

Wow, I never saw this! I like APL/J/Uiua, so this is perfect. Uiua is both stack and array based. Thanks!

concatenative code is sort of a natural fit for audio in terms of representing signal flow...

This is super cool. I've been thinking about doing something like this for awhile as a retirement project.

Oh it seems like forth is a pretty good candidate for this. Like most of these things are a post processing steps

Cagire

AGPL-3.0 · Raphaël Maurice Forment · 2026 · v0.1.9

Download

Platform	Terminal	Desktop
macOS (Universal)	zip	zip · dmg · app
Linux (x86_64)	zip · AppImage	zip · AppImage
Linux (ARM)	zip · AppImage	zip · AppImage
Windows (x86_64)	zip	zip

Source code and issue tracker on Gitea. You can also compile the software yourself from source!

About

Cagire is a step sequencer where each step contains a Forth script instead of typical note data. When the sequencer reaches a step, it runs the associated script. Scripts can produce sound, trigger samples, apply effects, or do nothing at all. You are free to define what your scripts will do. Cagire includes a built-in audio engine called Doux. No external software is needed to make sound. It comes with oscillators, sample players, filters, reverb, delay, distortion, and more.

Support

Cagire is free and open source, built by one person in my spare time. Donations keep the servers running, fund the hours I put into building it, and let me keep releasing it under a free license for everyone. If Cagire brings you joy, please consider chipping in.

♥ Support Cagire on Ko-fi

Documentation

Cagire ships with built-in interactive documentation. Browse it right inside the app, where every example is runnable on the spot. The manual is a full book, both a tutorial and a reference. It covers the interface, the two Forth-like languages and the sound engine. A printable edition of the same manual also exists.

The language

Cagire scripts are written in Forth, a concatenative language you read one word at a time, from right to left. One step can do many things, here is an example:

saw snd
< c4 eb3 g3 > note
[ .5 .8 ] choose gain
( 8 crush ) sometimes
0.5 decay
.

A second language, Arf, lives between curly braces and allows you to write your own DSP when the basics are not enough:

{
    110 saw 800 lpf
    out
} synth .

Features (click to learn more!)

Gallery

Sequencer view with a scope and spectrum visualizer, level meters and the 32-step grid

Main view with the sample browser open, showing a folder tree and a waveform preview

Step script editor defining a synth voice with an effects chain of reverb, flanger and delay

Patterns view with a bank grid, track lanes and a pattern properties panel

Dictionary view with a category tree beside Forth word entries and stack effects

Help view showing the engine manual page on spread and detune, with prose and Forth examples

Engine view showing OSC output configuration alongside level meters and an oscilloscope

Sampler view with a recorded waveform and a trim selection in edit mode

Black and white theme showing a step script editor with a stack visualizer

Live Coding

Live coding is a technique where a programmer writes code in real-time in front of an audience. It is a way to experiment with code, to share openly, to express yourself through code. It can be technical, poetical, weird, preferably all at once. Live coding can be used to create music, visual art, and other forms of media. Live coding is an autotelic activity: doing it is its own reward. There are no errors, only fun. Learn more at TOPLAP or livecoding.fr.

BuboBubo · Audio engine: Doux · Gitea · ♥ Ko-fi · AGPL-3.0

Hacker Times