I invented the first node editor for chords, procedural. Instead of writing chords one by one, you connect nodes: choose a key, add specific chords, and combine them with boolean operations (union, subtraction, intersection). You can filter (keep only the minor ones, add their secondary dominants), shuffle randomly while keeping dominants in place, transpose, insert 2-5-1s or inversions, and even click notes on a piano to generate all possible chords. Everything recalculates in real time. It's not a finished song — it's a playground to inspire you. Free for readers of my books.
Link to the node editor: https://briancallimusic.com/apps/bcm-nodes