An experimental evolutionary music generator that uses symbolic recombination instead of traditional randomness.
Each generation produces 48 unique MIDI sequences based on perfect shuffle crossover, and you — the listener — guide the evolution.

Originally written in PHP (2017). Now fully rebuilt in Node.js with a lightweight web interface.

• ✅ Simple browser-based interface for interactive selection
• 🎵 Generates 48 MIDI sequences per generation
• 🧬 Select your 16 favorite tracks and click Evolve to produce the next generation
• 🔁 Uses perfect shuffle crossover to blend melodies
• 🎲 Adds random "newbie" sequences to keep diversity alive
• 🎼 Based on a symbolic scale (default: natural minor)
• 🎚️ Tunable shift parameter subtly alters recombination rhythm
• 🧠 Zero machine learning — pure symbolic evolution

This project explores how structured crossover operations — like perfect shuffles — can produce meaningful musical patterns. Instead of noise or chaos, it uses symbolic determinism:
parent1 + parent2 → interleaved → offset → new generation.

It's like gene-splicing musical DNA — but with math and groove.

git clone https://github.com/xcontcom/perfect-shuffle-music-composer.git
cd perfect-shuffle-music-composer
npm install
node miditest.js

This project depends on:

midi-writer-js
express

Install via:

npm install midi-writer-js express

Then open your browser and go to:

http://localhost:3000

1. Visit the web interface.
2. Click to preview any of the 48 generated MIDI sequences.
3. Select exactly 16 that you like by checking the boxes.
4. Hit Evolve — a new generation will be created using perfect shuffle crossover.
5. Or click Recreate to generate a fresh random population.

Each new generation is built from:

• 16 survivors (top 16 selected by the user)
• 16 fresh individuals (randomly generated using a fixed scale)
• These parameters can be customized

Pairs of survivors are combined via perfect shuffle crossover:

for (let j = 0; j < notescount; j++) {
    tarray[j * 2] = parent1[j];
    tarray[j * 2 + 1] = parent2[j];
}

Then two children are formed by slicing this interleaved array with an optional offset (shift), like so:

child1[j] = tarray[j];
child2[j] = tarray[(j + shift) % tarray.length];

Changing shift tweaks the musical phrasing across generations.

Listen to Sample 1

Listen to Sample 2

Listen to Sample 2

Listen to Sample 2

legacy/                 # PHP
miditest.js             # Main Node.js app
public/
  └── midi/             # Output MIDI files
population.json         # Saved population data (auto-generated)
test.js                 # Different mixing method

Made by Serhii Herasymov, based on chaotic late-night discoveries in 2017 and reborn with clarity in 2025.

MIT License. See LICENSE for details.