Home : Tune Toys : Expresso 
  Expresso takes a simple musical expression (literally "X") and mutates it. In each generation, transformations are applied to components of the expression. This is a fractal technique known as an L-system. The more generations there are, the larger and more complex the expression gets (and the longer it can take to compute). The output varies wildly, from boring to fascinating. Press "Mutate" a few times till you get something that looks interesting, then click on the image to play it. See Composer's Quarry for examples of output.

Transformations:
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Phrase for X:
# of Tracks:
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After 20 generations the expression "X" became this:
shuffle(transpose((transpose(shuffle((((transpose((((((step(X,12) +transpose((((X|X) +transpose((X|X) ,4) ) +transpose(X,7) ) ,4) ) +transpose(shuffle(X) ,7) ) +transpose(echo(transpose(X,-5) ,4,6) ,4) ) +transpose(transpose(X,4) ,4) ) |transpose(transpose(transpose(transpose(X,-5) ,-5) ,-5) ,-7) ) ,-7) |((echo(transpose(shuffle(((X+transpose(X,7) ) +transpose(transpose(X,-7) ,7) ) ) ,-5) ,4,6) |transpose(X,4) ) +transpose(shuffle(transpose(transpose((X|X) ,-5) ,-7) ) ,7) ) ) +transpose(step(transpose(((((((((X+transpose(X,12) ) +transpose(X,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) |(X+X) ) +transpose(echo((X|X) ,4,6) ,12) ) +((step(X,12) +transpose(X,7) ) +transpose(X,4) ) ) +echo((X+transpose((step(X,12) |arpeggio(X) ) ,7) ) ,4,6) ) |((echo(((shuffle(X) |X) +((X+X) |transpose(X,-5) ) ) ,4,6) +transpose(arpeggio((((X+transpose((X+transpose(X,7) ) ,7) ) +transpose(arpeggio(X) ,4) ) +transpose(step(X,12) ,7) ) ) ,7) ) +transpose(transpose(step(((((X+X) +transpose(X,4) ) +transpose(X,7) ) +(X+X) ) ,12) ,-7) ,4) ) ) ,-7) ,12) ,7) ) +transpose((((transpose(transpose(X,4) ,-7) +transpose((transpose(X,-5) +transpose(X,-7) ) ,7) ) +transpose(transpose(transpose(arpeggio(X) ,4) ,-5) ,4) ) +transpose(transpose((transpose(transpose(X,-7) ,-5) |transpose((echo(X,4,6) +transpose(X,12) ) ,-7) ) ,4) ,7) ) ,-5) ) ) ,4) +transpose((transpose((((transpose(shuffle(((((X|shuffle(X) ) +transpose((X+transpose(X,12) ) ,4) ) +transpose((X+transpose(X,-7) ) ,7) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ) ) ,4) |(((transpose(X,4) +X) +transpose((X+transpose(transpose(X,4) ,7) ) ,7) ) +transpose(transpose((transpose(X,-5) +transpose(((X+transpose(X,7) ) +transpose(echo(X,4,6) ,12) ) ,12) ) ,-5) ,7) ) ) +arpeggio((((step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) +transpose(step(X,12) ,7) ) +transpose((step((X+transpose((X|X) ,7) ) ,12) +(arpeggio(X) |X) ) ,7) ) +step(echo(shuffle(transpose(X,-5) ) ,4,6) ,12) ) ) ) +transpose(step(echo(transpose(((echo(transpose(transpose(X,-7) ,-7) ,4,6) |(echo(step(X,12) ,4,6) |transpose(X,4) ) ) +(((arpeggio(transpose(X,4) ) +transpose(X,4) ) +transpose(transpose(transpose(X,-5) ,4) ,7) ) |step(transpose(echo(X,4,6) ,4) ,12) ) ) ,4) ,4,6) ,12) ,12) ) ,-7) +transpose((((((((shuffle((((echo(transpose(X,-7) ,4,6) +transpose((X+transpose(step(X,12) ,7) ) ,7) ) +transpose(arpeggio(transpose(X,-5) ) ,4) ) +transpose(transpose(X,-5) ,7) ) ) |shuffle(transpose(((shuffle(X) +transpose(transpose(transpose(transpose(X,-5) ,4) ,-5) ,7) ) +transpose(transpose((X+transpose(X,12) ) ,-5) ,-7) ) ,-7) ) ) +transpose((((transpose((step((transpose(X,4) +X) ,12) |transpose(X,-5) ) ,4) +transpose(((step(arpeggio(transpose((X|X) ,4) ) ,12) +transpose(step(((transpose(transpose(X,-5) ,-7) |transpose(X,4) ) +transpose(transpose(transpose(X,-5) ,-5) ,12) ) ,12) ,4) ) +transpose(transpose(((X+X) |arpeggio(shuffle(X) ) ) ,4) ,7) ) ,7) ) +transpose(shuffle((echo(transpose(transpose(X,-7) ,-5) ,4,6) +transpose((((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose(X,4) ,7) ) +transpose(arpeggio(transpose(X,-5) ) ,7) ) +transpose(((((arpeggio(X) +transpose((X+transpose(X,12) ) ,4) ) +transpose((X+X) ,7) ) +(X|X) ) +transpose(transpose(transpose(X,4) ,-7) ,7) ) ,7) ) ,7) ) ) ,4) ) +transpose(((transpose(transpose(step(((X+X) |X) ,12) ,-5) ,-7) +transpose((((((echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) +transpose((X|X) ,4) ) +transpose(((step(X,12) |X) +(X+transpose(X,4) ) ) ,7) ) +transpose(((X+transpose((X|X) ,7) ) |transpose((X+transpose(X,12) ) ,-5) ) ,12) ) +transpose((((transpose(echo(X,4,6) ,-5) +transpose((transpose(X,-5) +transpose(transpose(X,-5) ,7) ) ,4) ) +transpose(X,7) ) +transpose(((transpose(X,4) |step(X,12) ) +transpose(((X+transpose(X,4) ) +transpose(step(X,12) ,7) ) ,7) ) ,7) ) ,4) ) +transpose(((X+X) +transpose(X,-5) ) ,7) ) ,12) ) |(((transpose(X,4) +transpose((X|X) ,4) ) +transpose((X|X) ,7) ) +transpose(((transpose((X+transpose(X,12) ) ,4) +(((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose(X,-7) ,7) ) ) |(transpose(X,-7) +transpose((((X|X) |X) +transpose((transpose(X,-7) |X) ,7) ) ,12) ) ) ,12) ) ) ,7) ) ,7) ) |transpose(transpose(((transpose((transpose((echo(transpose(transpose(X,-7) ,4) ,4,6) +transpose((arpeggio(X) +transpose(shuffle(X) ,7) ) ,-7) ) ,4) +transpose((transpose(X,-7) |transpose(((transpose(X,-5) +transpose(X,12) ) +(X+transpose((X|X) ,12) ) ) ,4) ) ,12) ) ,-7) +transpose(transpose(transpose((transpose(shuffle(step(X,12) ) ,-5) |shuffle((step((X+X) ,12) +X) ) ) ,-7) ,-7) ,4) ) +transpose(((shuffle(((transpose(X,-7) |(X+(X|X) ) ) +transpose(transpose((shuffle(X) +(X+X) ) ,-7) ,12) ) ) +(transpose(transpose((X+transpose(X,12) ) ,4) ,-7) +(echo(echo(transpose(X,4) ,4,6) ,4,6) |((X+transpose(X,7) ) +(X+transpose(X,12) ) ) ) ) ) +(transpose(transpose(((X+transpose((X+transpose(X,7) ) ,4) ) +transpose((shuffle(X) |X) ,7) ) ,-7) ,-5) |shuffle((X+X) ) ) ) ,7) ) ,-7) ,-7) ) |transpose(transpose(arpeggio(shuffle((transpose(arpeggio(transpose(transpose((transpose(X,4) +step(X,12) ) ,-5) ,4) ) ,-7) +((shuffle(X) |transpose((X+X) ,4) ) |transpose((transpose((X+transpose(X,12) ) ,4) +echo(X,4,6) ) ,4) ) ) ) ) ,4) ,-5) ) +transpose(transpose(((transpose((transpose(echo((echo(transpose(X,4) ,4,6) |transpose(X,-5) ) ,4,6) ,4) |((transpose((step(X,12) +echo(X,4,6) ) ,-7) +transpose(transpose(echo(transpose((X+transpose(X,12) ) ,-7) ,4,6) ,-5) ,4) ) +transpose(arpeggio(step((echo(transpose((X+X) ,4) ,4,6) +transpose((transpose(X,-7) +transpose(transpose((X+transpose(X,7) ) ,-7) ,7) ) ,7) ) ,12) ) ,7) ) ) ,-7) +arpeggio(step(transpose(echo((arpeggio(X) +shuffle(X) ) ,4,6) ,-5) ,12) ) ) +(((((((((((X+transpose(X,4) ) +transpose(X,7) ) |(X+X) ) +shuffle(transpose(X,-7) ) ) +transpose((arpeggio(transpose(step(X,12) ,-7) ) +transpose(step((X+X) ,12) ,12) ) ,7) ) +transpose(X,4) ) +transpose((echo((((transpose((X+X) ,-7) +transpose(X,7) ) +transpose(shuffle(arpeggio(X) ) ,4) ) +transpose(((X+X) +transpose(step((X+X) ,12) ,7) ) ,7) ) ,4,6) |(X+transpose((transpose((transpose(X,4) +X) ,4) |shuffle((X+X) ) ) ,7) ) ) ,12) ) +transpose(step(((step(X,12) +transpose(((X+transpose(echo(X,4,6) ,7) ) +transpose((transpose(X,-5) |X) ,4) ) ,4) ) +transpose(arpeggio((shuffle(transpose(X,4) ) |step((X|X) ,12) ) ) ,7) ) ,12) ,7) ) |step(shuffle((transpose(transpose(X,4) ,-5) +transpose(transpose((X+transpose(X,7) ) ,4) ,12) ) ) ,12) ) |transpose(arpeggio(echo(echo(transpose(X,-7) ,4,6) ,4,6) ) ,-7) ) +transpose(shuffle((shuffle(((X+transpose(X,7) ) +transpose(transpose(X,4) ,7) ) ) +(X+transpose(transpose(((X+X) |echo(X,4,6) ) ,4) ,12) ) ) ) ,-5) ) ) ,4) ,4) ) +transpose((((transpose(transpose(((((((arpeggio(X) +transpose(echo(((X|X) |X) ,4,6) ,7) ) +transpose(transpose((X+transpose(arpeggio(X) ,12) ) ,-5) ,4) ) +transpose(transpose(X,4) ,7) ) +transpose(transpose(((transpose(transpose(echo(X,4,6) ,-5) ,-5) +transpose(step(X,12) ,4) ) +transpose(transpose(transpose((X|X) ,-7) ,4) ,7) ) ,-5) ,12) ) +transpose(((shuffle((arpeggio(X) +transpose(X,12) ) ) +transpose(((X+(X|X) ) |(arpeggio(X) +transpose(X,12) ) ) ,4) ) +transpose((arpeggio((X+X) ) |transpose(X,-5) ) ,7) ) ,7) ) +(transpose(shuffle((X+X) ) ,-7) +((arpeggio(((X|X) +X) ) +transpose((transpose(transpose(X,-7) ,4) +transpose((transpose(X,-5) +transpose(X,7) ) ,7) ) ,4) ) +transpose(transpose(transpose(arpeggio((X|X) ) ,-7) ,4) ,7) ) ) ) ,4) ,4) +transpose(transpose(transpose(((transpose(echo(X,4,6) ,4) |transpose(arpeggio(transpose(X,4) ) ,-5) ) +transpose(transpose(transpose(transpose(echo(X,4,6) ,-5) ,-7) ,-5) ,7) ) ,-7) ,-7) ,7) ) |((((transpose(((transpose(((X|X) +transpose((transpose(X,-7) |X) ,12) ) ,-5) +transpose((transpose(transpose(((X+X) +transpose((X+transpose(X,7) ) ,12) ) ,-5) ,-5) +transpose(((transpose(((X+transpose(X,12) ) +transpose(X,12) ) ,4) +transpose(step(X,12) ,4) ) +transpose((transpose(X,4) +((X+X) +transpose(transpose(X,-7) ,7) ) ) ,7) ) ,7) ) ,4) ) +transpose(echo(transpose(transpose(transpose(X,4) ,4) ,4) ,4,6) ,7) ) ,4) +transpose((((((((X+X) +transpose((X+X) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +X) ,7) ) |step(X,12) ) +transpose(echo(transpose(echo(X,4,6) ,4) ,4,6) ,4) ) +transpose(arpeggio(arpeggio(transpose(X,-7) ) ) ,7) ) +transpose((transpose((arpeggio(X) +transpose((X+X) ,7) ) ,-5) +transpose(transpose(X,-7) ,12) ) ,12) ) ,4) ) +transpose(transpose(((transpose((transpose(X,-5) +X) ,-7) +transpose(X,-7) ) +transpose((step(((X+transpose(X,7) ) |X) ,12) |(shuffle(X) |transpose((X|X) ,-5) ) ) ,7) ) ,-7) ,7) ) +transpose((((shuffle((step((X+transpose(X,7) ) ,12) |((X+X) |transpose(X,4) ) ) ) +transpose(step(transpose((transpose(transpose(X,-5) ,-7) +transpose(X,12) ) ,-5) ,12) ,12) ) +transpose((transpose((((X+transpose(X,4) ) +transpose(X,7) ) |transpose((X|X) ,4) ) ,-7) +arpeggio(((X+X) +transpose(((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(transpose(X,-5) ,7) ) ,7) ) ) ) ,12) ) +(shuffle(shuffle(X) ) +transpose(transpose((X+X) ,-5) ,12) ) ) ,7) ) +transpose(transpose(((transpose(arpeggio(X) ,-5) +arpeggio(shuffle(transpose(X,-7) ) ) ) +transpose(transpose(transpose(echo(echo(transpose(X,-5) ,4,6) ,4,6) ,4) ,-5) ,12) ) ,4) ,12) ) ) +(transpose((echo(((((X+transpose(transpose(transpose((X+transpose(X,7) ) ,-5) ,-7) ,4) ) +transpose(transpose(transpose(arpeggio(X) ,-5) ,4) ,7) ) |transpose(transpose(X,-7) ,-5) ) +transpose(step(((transpose(((X+transpose(X,7) ) +transpose(X,7) ) ,-5) +transpose(arpeggio(X) ,4) ) +transpose((shuffle(X) +(X+transpose(X,7) ) ) ,7) ) ,12) ,7) ) ,4,6) +(transpose((transpose(X,-7) +transpose(step(transpose(arpeggio(echo(X,4,6) ) ,4) ,12) ,7) ) ,-7) +transpose(((transpose(arpeggio(X) ,-7) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) +((arpeggio(X) +transpose((transpose(X,4) |transpose(X,-7) ) ,7) ) |(((transpose(X,-7) +X) +transpose((X+transpose(step(X,12) ,12) ) ,4) ) +transpose(((X+transpose(X,7) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,7) ) ) ) ,7) ) ) ,-5) +transpose(((transpose((X|X) ,-7) +transpose(echo(transpose(((X+X) |step(X,12) ) ,4) ,4,6) ,12) ) +(((transpose((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) |transpose(transpose(X,4) ,-5) ) ,-5) +transpose((X+step(arpeggio(X) ,12) ) ,4) ) +transpose(transpose(transpose(shuffle((step(X,12) +transpose(transpose(X,-7) ,7) ) ) ,-7) ,4) ,7) ) +transpose(((((transpose(X,4) +transpose(shuffle((shuffle(X) |shuffle(X) ) ) ,4) ) +transpose(X,7) ) +transpose((((X+transpose(X,12) ) +transpose(arpeggio((X+X) ) ,7) ) |((X|X) +transpose(transpose(X,4) ,7) ) ) ,4) ) +transpose(transpose(X,-5) ,7) ) ,7) ) ) ,-7) ) ) ,7) ) +transpose(step(step(transpose((transpose((transpose((((transpose(echo((X+X) ,4,6) ,-5) |((step(X,12) +transpose(arpeggio(X) ,4) ) +transpose(((X+transpose(transpose(X,-5) ,4) ) +transpose(X,7) ) ,7) ) ) +transpose(arpeggio(transpose((X+X) ,4) ) ,4) ) +transpose(((echo((X+transpose(X,12) ) ,4,6) +X) +((echo(X,4,6) +transpose(((X+transpose((X+transpose(X,7) ) ,4) ) +transpose(step(X,12) ,7) ) ,4) ) +transpose(((X|X) +arpeggio(X) ) ,7) ) ) ,7) ) ,-7) +echo(transpose(X,4) ,4,6) ) ,-7) |(transpose(shuffle(echo((transpose(X,4) +transpose((step(X,12) +X) ,12) ) ,4,6) ) ,-5) +transpose((((transpose(echo(X,4,6) ,-5) +transpose(X,7) ) +shuffle(transpose(X,-5) ) ) +(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+X) ,7) ) |transpose(transpose(X,4) ,-5) ) |X) ) ,12) ) ) ,4) ,12) ,12) ,7) ) ,7) ) ,12) ) ,4) )
random seed used was 3442951 EXPR = (echo((arpeggio((transpose(transpose((transpose(X,-7) +((echo(X,4,6) +transpose(X,7) ) +transpose(X,4) ) ) ,-5) ,-7) +(echo((transpose(X,4) +transpose(X,12) ) ,4,6) +step((((X+transpose(X,12) ) +transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) ,12) ) ) ) |echo(transpose((((transpose(echo(X,4,6) ,-7) +transpose(shuffle((((X|X) +transpose(transpose(X,-7) ,7) ) |step((X|X) ,12) ) ) ,4) ) +transpose(step(transpose((X+X) ,-5) ,12) ,7) ) |((arpeggio((X+transpose(transpose(X,-7) ,7) ) ) |((X+transpose(shuffle(X) ,4) ) +transpose(transpose(X,-5) ,7) ) ) +(arpeggio(((X|X) +(X|X) ) ) +transpose(transpose(transpose(echo(X,4,6) ,4) ,-7) ,7) ) ) ) ,-7) ,4,6) ) ,4,6) +transpose(step(((((step((echo(transpose(transpose((transpose(X,-5) |transpose((((X+transpose(X,12) ) +transpose((X+X) ,4) ) +transpose(X,7) ) ,4) ) ,-7) ,-7) ,4,6) +transpose(transpose(transpose(step(echo(transpose(X,-5) ,4,6) ,12) ,-5) ,4) ,12) ) ,12) +transpose((((((transpose(transpose(((arpeggio(X) +transpose(transpose(X,-7) ,7) ) +transpose(arpeggio((X+X) ) ,12) ) ,-5) ,4) +transpose(echo(((((X+X) +transpose(((X|X) +transpose(X,12) ) ,4) ) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ,7) ) +transpose(((shuffle(X) |step(X,12) ) +transpose(arpeggio(X) ,12) ) ,7) ) ,4,6) ,12) ) +transpose(((transpose(echo((((X+transpose(X,12) ) +transpose(X,4) ) +transpose(arpeggio(transpose(X,-5) ) ,7) ) ,4,6) ,-5) +(((((transpose(X,4) +transpose(transpose(X,-5) ,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose(transpose(echo(transpose(X,4) ,4,6) ,-5) ,4) ) +transpose(((shuffle(X) +transpose((X+X) ,4) ) +transpose((X+X) ,7) ) ,7) ) ) +transpose(transpose((echo(X,4,6) +transpose(arpeggio(arpeggio(X) ) ,12) ) ,4) ,7) ) ,7) ) +transpose(transpose(transpose(transpose((X+transpose((echo((X+X) ,4,6) |transpose(transpose(X,-7) ,-5) ) ,12) ) ,-5) ,-7) ,-5) ,4) ) +transpose((((echo(echo(X,4,6) ,4,6) +transpose((arpeggio(transpose(X,-5) ) +transpose(transpose(step(X,12) ,-5) ,4) ) ,12) ) |(((((X+X) +(X+transpose(X,12) ) ) +transpose((X|X) ,7) ) +transpose(shuffle(transpose((X+transpose(X,12) ) ,4) ) ,4) ) +transpose(transpose(X,4) ,7) ) ) |shuffle((arpeggio(transpose(((X+X) +(X+X) ) ,4) ) +transpose(shuffle((transpose(X,4) |X) ) ,4) ) ) ) ,7) ) +transpose((((echo(((arpeggio((X+X) ) +transpose(transpose(X,-5) ,4) ) +transpose(X,7) ) ,4,6) +(X+transpose(X,7) ) ) +transpose(transpose(step(transpose(echo(transpose(X,4) ,4,6) ,-7) ,12) ,-5) ,12) ) +transpose(((transpose(X,4) +transpose(((X+transpose(step(X,12) ,4) ) +transpose(shuffle(X) ,7) ) ,12) ) +transpose(arpeggio(step(echo(X,4,6) ,12) ) ,7) ) ,7) ) ,-5) ) ,12) ) +transpose(((transpose(((transpose((X+X) ,-5) +transpose(arpeggio((transpose(echo(arpeggio(X) ,4,6) ,-7) +transpose(arpeggio((transpose(X,4) +transpose(X,7) ) ) ,7) ) ) ,7) ) +arpeggio((transpose(transpose(X,-5) ,4) +transpose(transpose(X,-7) ,12) ) ) ) ,4) +transpose(transpose((((transpose((((X+X) +(X|X) ) +transpose((transpose(X,-5) +(X|X) ) ,7) ) ,-5) |transpose(X,-7) ) +transpose(step(((transpose(transpose(((X+transpose(X,12) ) +transpose(X,12) ) ,4) ,-5) +transpose((((transpose(X,4) +transpose(X,4) ) +transpose(transpose(X,4) ,7) ) |(transpose(X,-7) +(X+transpose(X,12) ) ) ) ,7) ) |transpose(transpose(echo(X,4,6) ,-5) ,-5) ) ,12) ,4) ) +transpose(step((((step(transpose(X,4) ,12) |X) +transpose(transpose(((transpose(X,-5) +transpose((X+X) ,4) ) +transpose(X,7) ) ,-7) ,4) ) +transpose(transpose(echo(X,4,6) ,4) ,7) ) ,12) ,7) ) ,-7) ,7) ) +transpose(transpose(echo((((transpose(transpose(transpose(transpose((transpose(X,4) +transpose((X+transpose(X,12) ) ,12) ) ,-5) ,4) ,-5) ,-5) |transpose((arpeggio(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) |(((transpose(X,-7) +transpose((shuffle(X) +transpose(X,-5) ) ,4) ) +transpose(((transpose(X,4) +transpose(X,4) ) +transpose((X+X) ,7) ) ,7) ) +transpose((((transpose((X|X) ,-7) +transpose(X,7) ) +transpose(step(X,12) ,4) ) +transpose(transpose(((X+transpose(X,7) ) +(X+X) ) ,-5) ,7) ) ,12) ) ) ,-5) ) +transpose(transpose((((transpose((X+transpose(X,7) ) ,4) +transpose(X,-5) ) +((transpose(X,-5) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ) +(transpose(transpose(echo(step(X,12) ,4,6) ,4) ,4) +transpose((transpose(transpose(X,-7) ,-5) +transpose(transpose(X,-5) ,7) ) ,7) ) ) ,4) ,4) ) +transpose(step(transpose((transpose(transpose(transpose(((X+transpose(X,12) ) +transpose((X+X) ,12) ) ,4) ,-5) ,4) |(((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(echo(X,4,6) ,7) ) ,12) ) ) ,4) ,12) ,7) ) ,4,6) ,-7) ,12) ) ,4) ) +transpose(((((step((shuffle((arpeggio(transpose(transpose(X,4) ,-7) ) +((X+transpose(X,4) ) +transpose((X+(X+transpose(X,12) ) ) ,7) ) ) ) +transpose((transpose(((X+transpose(X,12) ) +(X|X) ) ,-5) +transpose(transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(echo(X,4,6) ,-7) ) ,-7) ,-5) ) ,12) ) ,12) |(((X|transpose(X,4) ) +transpose((shuffle((((X+X) +transpose(X,-7) ) +(transpose(X,-5) +transpose(X,7) ) ) ) +transpose(echo(echo(X,4,6) ,4,6) ,12) ) ,4) ) +transpose(shuffle(step(((transpose(X,-7) +transpose(X,12) ) |transpose(X,4) ) ,12) ) ,7) ) ) +arpeggio(echo((step(transpose(X,-5) ,12) |transpose(((X+transpose(shuffle(X) ,4) ) +transpose(X,7) ) ,-5) ) ,4,6) ) ) |transpose(transpose(transpose((transpose((X+transpose(X,7) ) ,-5) +(X+X) ) ,4) ,-7) ,-7) ) +transpose(transpose(((((transpose((transpose(X,-5) +(X+X) ) ,4) +transpose(arpeggio(((X+transpose(X,12) ) +transpose(((transpose(X,-7) +transpose(X,4) ) +transpose(step(X,12) ,7) ) ,12) ) ) ,4) ) +transpose(((X+transpose(transpose(X,-5) ,4) ) +transpose((X+X) ,7) ) ,7) ) +transpose(transpose(((transpose(transpose(X,4) ,-7) +transpose((X+transpose(X,7) ) ,4) ) +transpose((X+X) ,7) ) ,-7) ,12) ) +shuffle(step(transpose(X,4) ,12) ) ) ,4) ,12) ) ,7) ) +(transpose((transpose((transpose((transpose(X,-7) |X) ,4) +transpose((((X+(X|X) ) +transpose(echo(((X+X) +transpose((X+transpose(X,12) ) ,12) ) ,4,6) ,7) ) |(((echo(X,4,6) +transpose((X+X) ,12) ) +transpose(transpose((X+transpose(step(X,12) ,12) ) ,-7) ,4) ) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ,7) ) ) ,7) ) ,-5) +transpose(((transpose(shuffle((transpose(((X+transpose(X,7) ) +echo(X,4,6) ) ,-5) |transpose(((X+transpose(transpose(X,-7) ,7) ) +transpose(X,12) ) ,-7) ) ) ,4) +((shuffle(X) +transpose((((X|X) +transpose((X+transpose(X,12) ) ,4) ) +transpose(X,7) ) ,12) ) +transpose(((transpose(transpose((X|X) ,-5) ,-5) +transpose((X|transpose(X,4) ) ,-5) ) |echo(transpose(X,-7) ,4,6) ) ,-7) ) ) |(transpose(((((X+transpose(X,4) ) +transpose(transpose(X,-5) ,7) ) +transpose((transpose(X,-5) +transpose(shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) ,7) ) ,4) ) +transpose(step(transpose(arpeggio(X) ,-5) ,12) ,7) ) ,4) +transpose(((shuffle(transpose(transpose(X,-5) ,4) ) |transpose(transpose(transpose(X,-7) ,-5) ,-5) ) |transpose((X|transpose(X,4) ) ,4) ) ,7) ) ) ,-7) ) ,-7) +echo(transpose(transpose(transpose(transpose(transpose(X,4) ,-5) ,4) ,-7) ,4) ,4,6) ) ) ,12) ,7) )
random seed used was 0 EXPR = shuffle(arpeggio(transpose((transpose(((transpose(transpose((((transpose((X+transpose(X,12) ) ,-7) |((X+step(X,12) ) |(X+transpose(transpose(X,-7) ,7) ) ) ) +step(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ,12) ) |((transpose((transpose(X,4) +X) ,4) +transpose(((X+transpose(X,7) ) |(((X+transpose(X,7) ) +transpose(X,4) ) +transpose(shuffle(X) ,7) ) ) ,4) ) +transpose(((transpose(X,-5) |(transpose(X,4) +(X+X) ) ) +transpose(transpose(((X+X) +transpose(transpose(X,-7) ,12) ) ,4) ,12) ) ,12) ) ) ,-5) ,-5) +(transpose((transpose((X|X) ,4) +shuffle(arpeggio(X) ) ) ,-7) +((((arpeggio(transpose(shuffle((X+transpose(X,12) ) ) ,-5) ) +transpose(transpose(X,-5) ,4) ) +transpose(((X+transpose(transpose(X,-5) ,12) ) +(X+transpose(X,12) ) ) ,7) ) +transpose(transpose((X+transpose(transpose(X,-5) ,-5) ) ,-7) ,7) ) +transpose(transpose(((transpose(X,4) +transpose((X|X) ,4) ) +transpose(((X+transpose(step(X,12) ,4) ) +transpose((X|X) ,7) ) ,7) ) ,4) ,7) ) ) ) +transpose(arpeggio(transpose(transpose(transpose(transpose(X,-7) ,4) ,-5) ,4) ) ,12) ) ,-5) |shuffle(((((transpose((((echo(transpose(transpose(X,-5) ,-7) ,4,6) +transpose(X,4) ) |((shuffle(X) +transpose(transpose(arpeggio((X+X) ) ,-5) ,7) ) +transpose(transpose(shuffle(transpose(step(X,12) ,-5) ) ,-5) ,12) ) ) |echo(step((shuffle(((shuffle(X) +transpose(X,7) ) |transpose(transpose((X+transpose(X,12) ) ,-7) ,-7) ) ) +(transpose(step(X,12) ,4) |(((X+transpose(transpose(X,-7) ,4) ) +transpose(transpose(X,-7) ,7) ) |transpose(X,4) ) ) ) ,12) ,4,6) ) ,-5) +transpose((step((transpose(transpose((X|X) ,-7) ,4) +transpose(X,12) ) ,12) +transpose((transpose((((step(shuffle(X) ,12) |shuffle(transpose(X,4) ) ) +(arpeggio(X) +transpose(transpose(X,4) ,12) ) ) |transpose(X,-5) ) ,-5) |transpose(transpose((transpose(X,4) +transpose((((echo(transpose(X,-5) ,4,6) +(X|transpose(X,-7) ) ) +transpose((X|X) ,4) ) +transpose(shuffle(transpose(X,4) ) ,7) ) ,12) ) ,-5) ,4) ) ,7) ) ,4) ) +transpose((transpose(transpose(arpeggio(transpose(((transpose(transpose(X,-5) ,-7) +step(X,12) ) +(((X+transpose(X,4) ) +transpose(shuffle(X) ,7) ) +X) ) ,-5) ) ,-7) ,-7) +arpeggio(((transpose(step((transpose(X,-7) |transpose(((transpose((X|X) ,-5) +transpose((X+X) ,4) ) +transpose((X+X) ,7) ) ,-5) ) ,12) ,-5) +transpose((echo(transpose(echo(X,4,6) ,-7) ,4,6) |((echo(X,4,6) |X) +transpose(shuffle((transpose(X,4) +transpose(X,-5) ) ) ,7) ) ) ,7) ) +transpose(echo((echo(transpose(X,-5) ,4,6) |(transpose(transpose((X+transpose(X,7) ) ,-5) ,4) +transpose(echo((X|X) ,4,6) ,12) ) ) ,4,6) ,12) ) ) ) ,4) ) +transpose(step(echo(echo(((transpose((arpeggio(X) +X) ,-7) |arpeggio((X|X) ) ) |transpose(transpose((arpeggio(X) |(X+transpose(X,12) ) ) ,-5) ,-5) ) ,4,6) ,4,6) ,12) ,7) ) +(transpose(((transpose(transpose(transpose(((X+X) +transpose((X+transpose(X,7) ) ,12) ) ,-5) ,-5) ,4) +transpose((step(transpose(arpeggio(X) ,4) ,12) +(((X+transpose(X,12) ) |(X+transpose(X,7) ) ) +X) ) ,7) ) +transpose(((shuffle(X) +transpose(X,12) ) +transpose(shuffle(X) ,12) ) ,-7) ) ,-5) +transpose(transpose(((transpose((step(transpose((X|(((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+X) ,7) ) ) ,-5) ,12) +transpose(((transpose(X,-7) +transpose(echo(X,4,6) ,7) ) +transpose((shuffle(transpose((X+transpose(X,7) ) ,4) ) +transpose((X+X) ,4) ) ,12) ) ,7) ) ,4) +transpose(transpose(((transpose(X,-5) +X) |transpose(X,4) ) ,-7) ,4) ) +transpose((step((echo((((transpose(X,-7) +transpose(X,4) ) +transpose((X|X) ,7) ) +(step(X,12) |echo(X,4,6) ) ) ,4,6) +transpose(arpeggio(transpose(echo((((X+transpose(X,12) ) +transpose(transpose(X,4) ,4) ) +transpose(transpose(X,-7) ,7) ) ,4,6) ,-7) ) ,12) ) ,12) +transpose(shuffle(transpose(((echo(X,4,6) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,-7) ) ,4) ) +transpose(((X+transpose(X,12) ) +X) ,7) ) ,4) ) ,12) ) ,12) ) ,-5) ,12) ) ) ) ) ,-7) ) )
random seed used was 0

The algorithm for Expresso is written in KeyKit, and here's the source code.