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:
transpose((transpose(step(step((((((step(transpose(step((((step(X,12) +transpose((X|X) ,4) ) +transpose(transpose(X,4) ,7) ) +transpose((transpose(X,-5) +X) ,4) ) ,12) ,4) ,12) |transpose((transpose((arpeggio(((X+X) |(X+X) ) ) +transpose((transpose(X,4) +transpose(transpose(echo(X,4,6) ,4) ,12) ) ,-5) ) ,4) +transpose((transpose(transpose(X,-5) ,-5) +transpose(transpose(transpose((X+X) ,-5) ,4) ,12) ) ,4) ) ,-7) ) +transpose(transpose(step(shuffle(((((transpose(transpose(transpose(X,-5) ,4) ,-5) +transpose(X,7) ) +transpose(transpose((X|X) ,-5) ,4) ) +transpose(arpeggio(arpeggio(arpeggio((X|X) ) ) ) ,4) ) +transpose(arpeggio(transpose(shuffle(X) ,-5) ) ,7) ) ) ,12) ,-7) ,4) ) +transpose((shuffle(arpeggio((transpose(echo(shuffle(transpose(X,-5) ) ,4,6) ,-7) +transpose(transpose((echo((X|X) ,4,6) +transpose((transpose(step(shuffle(X) ,12) ,4) +transpose(echo(transpose((shuffle(X) +X) ,4) ,4,6) ,7) ) ,12) ) ,-7) ,7) ) ) ) +transpose((((arpeggio(shuffle(step(arpeggio((X|X) ) ,12) ) ) |transpose(arpeggio(transpose((X+shuffle(X) ) ,4) ) ,-5) ) +transpose(transpose(transpose(step(step(shuffle(X) ,12) ,12) ,-7) ,-5) ,4) ) +transpose((transpose(shuffle(transpose(X,-7) ) ,-5) +transpose(transpose((shuffle(X) |X) ,-7) ,12) ) ,7) ) ,7) ) ,7) ) +transpose(transpose(transpose(arpeggio(transpose((transpose((step(X,12) +transpose(X,12) ) ,-5) +(X+(((shuffle(X) |X) +transpose((shuffle(X) |X) ,4) ) +transpose((X+X) ,7) ) ) ) ,-5) ) ,-7) ,4) ,12) ) |(echo(transpose(((transpose(((((transpose(echo(transpose(X,-5) ,4,6) ,-7) +transpose(echo((X+X) ,4,6) ,4) ) +transpose(echo((X|X) ,4,6) ,7) ) +transpose(transpose(step(X,12) ,4) ,12) ) |(shuffle(X) +((X|transpose(X,-5) ) +transpose((transpose(X,-5) +step(X,12) ) ,7) ) ) ) ,-5) +transpose(((echo(shuffle(((X+transpose(X,12) ) +transpose(X,-7) ) ) ,4,6) |transpose(arpeggio(transpose(X,4) ) ,4) ) +transpose((X|(transpose(X,-7) |X) ) ,-5) ) ,7) ) +transpose(((shuffle((transpose(((transpose(transpose(transpose(X,-7) ,-5) ,-7) |(X+transpose(X,12) ) ) +transpose(arpeggio(transpose(X,-7) ) ,7) ) ,-7) |((arpeggio(echo(X,4,6) ) |transpose(transpose(X,-7) ,-5) ) |transpose(transpose((X+((X|X) |X) ) ,-5) ,-7) ) ) ) +transpose((transpose((((X+X) +transpose(((transpose(X,-7) +transpose(transpose(X,4) ,4) ) +transpose(((X|X) +X) ,7) ) ,-5) ) +step(X,12) ) ,-5) +transpose(step((transpose((X|X) ,-5) |transpose(transpose(transpose(X,4) ,4) ,4) ) ,12) ,7) ) ,4) ) +transpose(transpose((step(transpose(X,4) ,12) |(((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose((transpose(X,-7) |transpose(X,-5) ) ,-5) ,7) ) ) ,-5) ,7) ) ,7) ) ,-5) ,4,6) +transpose((transpose(transpose(step(((transpose((X+X) ,-5) +transpose(transpose((transpose((X+X) ,4) +transpose(X,4) ) ,4) ,12) ) +transpose(((echo(((X+transpose(X,12) ) +transpose((echo(X,4,6) +((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ) ,4,6) +transpose(X,4) ) +transpose(((X|X) +transpose(transpose(shuffle(X) ,4) ,7) ) ,7) ) ,12) ) ,12) ,-7) ,-7) +transpose((arpeggio((transpose(transpose(transpose(arpeggio(X) ,-7) ,-5) ,4) +transpose((X+transpose(transpose(transpose(X,4) ,-7) ,7) ) ,7) ) ) +transpose(((((((X+transpose(shuffle(X) ,12) ) +transpose(transpose(echo(X,4,6) ,4) ,4) ) +transpose((((shuffle(transpose(X,-7) ) +transpose((X|X) ,4) ) +transpose(transpose(X,4) ,7) ) |transpose(echo(X,4,6) ,-7) ) ,7) ) +transpose((transpose(transpose(((X+transpose((X+transpose(X,7) ) ,4) ) +transpose(transpose(X,4) ,7) ) ,4) ,4) |((((X+transpose(X,12) ) +transpose(X,12) ) +transpose(transpose(X,4) ,7) ) +transpose(transpose(X,-7) ,12) ) ) ,4) ) +transpose(((X+X) +transpose(transpose(((transpose(X,-5) +transpose(X,4) ) +transpose(((X+transpose(X,7) ) +transpose(transpose(X,-5) ,12) ) ,7) ) ,-5) ,12) ) ,7) ) +echo((step(transpose(X,4) ,12) +transpose(((arpeggio(X) +transpose(step((X+X) ,12) ,4) ) +transpose((X|X) ,7) ) ,12) ) ,4,6) ) ,7) ) ,7) ) ,-5) ) ) ,12) ,12) ,4) +transpose((((step(echo(echo(transpose((arpeggio(transpose(((((((X+transpose(X,4) ) +transpose(X,7) ) |(X|X) ) +shuffle(X) ) +transpose(((X|(X+X) ) |transpose(X,4) ) ,12) ) +transpose((transpose(transpose(transpose(X,-5) ,-5) ,-7) +transpose((X+echo(X,4,6) ) ,12) ) ,7) ) ,4) ) +transpose(transpose(((shuffle(transpose(arpeggio(X) ,4) ) +transpose((transpose(echo(transpose(X,4) ,4,6) ,4) +echo(X,4,6) ) ,7) ) +(((X+(X+transpose(X,12) ) ) +transpose(((X+transpose(((X+X) +transpose(X,12) ) ,4) ) +transpose(X,7) ) ,4) ) +transpose(((((X+transpose(arpeggio(X) ,7) ) +transpose(X,4) ) +transpose(echo((X+transpose(X,7) ) ,4,6) ,7) ) |echo(X,4,6) ) ,7) ) ) ,4) ,-5) ) ,-7) ,4,6) ,4,6) ,12) |transpose(transpose(((step((transpose(X,-5) +echo((shuffle(((X|X) |(X|(X|X) ) ) ) |transpose(transpose(X,-5) ,-5) ) ,4,6) ) ,12) |shuffle(transpose(echo(transpose(arpeggio(transpose(X,-5) ) ,-7) ,4,6) ,-7) ) ) +transpose(((transpose((arpeggio(((((arpeggio(transpose(X,-7) ) +transpose((X+transpose((X+X) ,7) ) ,12) ) +(step(transpose(X,4) ,12) +transpose((((X+X) +transpose(arpeggio(X) ,4) ) +transpose(transpose(X,-7) ,7) ) ,12) ) ) +transpose((transpose(transpose(X,-7) ,-5) |echo(X,4,6) ) ,4) ) +transpose((((X+transpose(X,7) ) +transpose((((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) +transpose(step(X,12) ,7) ) +transpose(((transpose(X,4) |echo(X,4,6) ) +transpose(transpose(X,-7) ,12) ) ,4) ) +transpose(step(X,12) ,7) ) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose((shuffle(X) |X) ,-5) ,7) ) ,7) ) ,7) ) ) +arpeggio(transpose(transpose((X+transpose((X+transpose(X,7) ) ,12) ) ,-7) ,-5) ) ) ,-5) |transpose((transpose(((((transpose(X,-7) +transpose((transpose(X,4) |((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ) |(((X+X) +transpose(transpose(X,-7) ,4) ) +transpose(X,7) ) ) +transpose(shuffle((transpose(X,4) |(transpose(X,-7) +transpose(transpose(X,-7) ,12) ) ) ) ,4) ) +transpose(transpose((X+transpose(X,-7) ) ,4) ,7) ) ,4) +transpose(transpose((arpeggio((transpose(((X|X) +transpose((X|X) ,12) ) ,-7) |(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) +X) ) ) |((X+transpose(X,12) ) +transpose(X,4) ) ) ,4) ,12) ) ,4) ) +transpose(transpose(step(shuffle(((transpose((X|X) ,4) +transpose(transpose(transpose((X|(X+transpose(X,12) ) ) ,4) ,-7) ,7) ) +echo((((X+X) +transpose(X,12) ) +transpose((X+X) ,12) ) ,4,6) ) ) ,12) ,4) ,7) ) ,12) ) ,-5) ,-7) ) +transpose(((step(((transpose(((transpose(((X+X) +transpose(transpose(X,-5) ,12) ) ,-7) |transpose(transpose(X,-7) ,-5) ) +transpose(transpose((transpose(X,-7) |X) ,4) ,12) ) ,-7) +transpose((((X+transpose(X,12) ) +transpose((X+transpose((X|X) ,12) ) ,4) ) +transpose(echo(transpose(X,-7) ,4,6) ,7) ) ,12) ) +transpose(transpose(X,4) ,7) ) ,12) +((echo(((transpose(arpeggio(transpose(step(arpeggio(X) ,12) ,-5) ) ,-7) +transpose(arpeggio((X|((arpeggio(X) +transpose(transpose(X,-5) ,4) ) +transpose(shuffle(X) ,7) ) ) ) ,4) ) +transpose(transpose((X|X) ,-5) ,7) ) ,4,6) +transpose(transpose(((((arpeggio(X) |X) +transpose(X,7) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +(X+X) ) ,4) ) +transpose((X+transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,12) ) ,7) ) ,-7) ,7) ) |transpose((transpose(((step(transpose(X,-7) ,12) +transpose(transpose((echo(X,4,6) +transpose(transpose(X,4) ,12) ) ,-7) ,4) ) +transpose(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ,7) ) ,4) +transpose(transpose((transpose(transpose(transpose((X+X) ,-5) ,-5) ,-5) +transpose(transpose(transpose(arpeggio(X) ,-5) ,-5) ,7) ) ,4) ,12) ) ,-5) ) ) |((((((shuffle(transpose(step(X,12) ,-7) ) +transpose(arpeggio((shuffle(transpose((transpose(X,-5) |(X+X) ) ,4) ) +echo(arpeggio((((((X+transpose(X,12) ) +transpose((X|X) ,4) ) +transpose(transpose(X,4) ,7) ) +transpose(transpose(X,4) ,12) ) |step(arpeggio(X) ,12) ) ) ,4,6) ) ) ,12) ) +transpose((((transpose(transpose((X+transpose(X,12) ) ,-5) ,-7) +transpose(step(transpose(X,-5) ,12) ,4) ) +transpose(shuffle((X|X) ) ,7) ) +transpose((transpose(((transpose(arpeggio(X) ,4) +transpose((step((X+transpose(X,7) ) ,12) +transpose(transpose(transpose(X,-7) ,4) ,12) ) ,4) ) +transpose((echo(X,4,6) |shuffle(X) ) ,7) ) ,4) +transpose(step(transpose(transpose((X+X) ,4) ,4) ,12) ,7) ) ,7) ) ,12) ) +transpose((((transpose(((((X+(X+X) ) +transpose(((X|X) |transpose(X,4) ) ,4) ) +transpose(transpose((X|X) ,4) ,7) ) |transpose(transpose((X+X) ,-7) ,-7) ) ,-5) |transpose((X+(X+(X+X) ) ) ,-7) ) +transpose((((step(arpeggio(X) ,12) +X) +transpose(transpose((echo(X,4,6) |X) ,4) ,12) ) +shuffle(((transpose(transpose((X+transpose(X,7) ) ,-7) ,4) |(X+((X+transpose(X,4) ) +transpose(X,7) ) ) ) +transpose((((X+transpose(X,12) ) +X) +transpose(X,7) ) ,12) ) ) ) ,4) ) +transpose(step(transpose(echo(transpose(X,4) ,4,6) ,4) ,12) ,7) ) ,-7) ) +transpose(((transpose(transpose((transpose(((step(transpose(X,4) ,12) +transpose((X+transpose(transpose(shuffle(X) ,-7) ,7) ) ,4) ) +transpose((((X+X) +transpose(X,12) ) +(X+X) ) ,7) ) ,-5) +arpeggio((transpose(transpose(X,4) ,-7) |transpose((X+transpose(X,7) ) ,4) ) ) ) ,-7) ,-7) +(transpose(transpose((step(shuffle(X) ,12) +transpose(transpose(transpose(X,-7) ,-5) ,7) ) ,-7) ,4) |transpose((transpose(((X|transpose(X,4) ) +transpose(((arpeggio((X+X) ) +transpose(X,4) ) +transpose(transpose(X,-5) ,7) ) ,12) ) ,4) +transpose(echo((echo(X,4,6) +transpose((X|X) ,12) ) ,4,6) ,-7) ) ,4) ) ) +transpose(((transpose(transpose(transpose(transpose(X,-7) ,4) ,4) ,-7) +arpeggio(transpose((shuffle(X) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,7) ) ,-7) ) ) +transpose((((((X+X) +transpose((transpose(shuffle(echo(X,4,6) ) ,-5) +transpose(transpose(X,-5) ,7) ) ,12) ) +(((arpeggio(transpose(X,-7) ) |echo(transpose(X,4) ,4,6) ) |(echo(transpose(X,4) ,4,6) +transpose(X,12) ) ) +(((X+transpose(X,12) ) +(shuffle((X+transpose(X,12) ) ) |((X|X) +transpose(step(X,12) ,12) ) ) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ) ) +transpose(arpeggio((((X+transpose((X|shuffle(X) ) ,4) ) +transpose(step(transpose(X,-7) ,12) ,7) ) |(((X+transpose((((X|X) +transpose((X+transpose(X,12) ) ,4) ) +transpose(X,7) ) ,4) ) +transpose(transpose(X,-5) ,7) ) |step((X+(X+transpose(X,12) ) ) ,12) ) ) ) ,7) ) +(transpose((transpose((X+X) ,-5) +transpose(shuffle(((transpose(transpose(X,4) ,-5) +transpose(X,4) ) +transpose(transpose((X+transpose(X,7) ) ,-5) ,7) ) ) ,12) ) ,-7) |arpeggio(((transpose((transpose((X|X) ,-5) +(X+X) ) ,-5) |(((X+transpose(X,12) ) |transpose(X,-5) ) +(shuffle(X) +transpose((X|X) ,7) ) ) ) +transpose(transpose(transpose((step(X,12) +transpose(X,12) ) ,-7) ,-7) ,12) ) ) ) ) ,12) ) ,12) ) ,12) ) +transpose((arpeggio(step(echo(transpose((X|X) ,-5) ,4,6) ,12) ) +transpose((transpose(((transpose(X,-5) +transpose(transpose(transpose(X,4) ,-5) ,7) ) |((transpose(transpose(X,-7) ,-7) +transpose(transpose((X|X) ,-7) ,4) ) +transpose((step(X,12) +transpose(X,12) ) ,7) ) ) ,-7) |((transpose(transpose((transpose(step((X|((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ,-5) |((arpeggio(X) +transpose(transpose(X,-7) ,7) ) +transpose(X,12) ) ) ,-5) ,-7) +transpose(((transpose(X,-7) +transpose(X,12) ) +transpose(step(step((X+transpose(X,12) ) ,12) ,12) ,-7) ) ,4) ) +transpose(echo((echo(echo(X,4,6) ,4,6) |echo(transpose((X|X) ,-5) ,4,6) ) ,4,6) ,7) ) ) ,12) ) ,4) ) +transpose((transpose((shuffle(transpose((((X+(X+transpose((X+X) ,7) ) ) |echo(step(X,12) ,4,6) ) +transpose((transpose(X,-7) |arpeggio((X+transpose(X,12) ) ) ) ,12) ) ,4) ) +echo((transpose((arpeggio((X+X) ) +(((X+transpose((X+transpose(X,12) ) ,7) ) +transpose(echo(X,4,6) ,7) ) |transpose(X,4) ) ) ,4) +(arpeggio(((arpeggio(X) +transpose(X,4) ) +transpose((X|X) ,7) ) ) +transpose(((X+transpose((X+X) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,12) ) ) ,4,6) ) ,-7) +transpose((step(shuffle(transpose(((X+X) +X) ,-7) ) ,12) +transpose(((transpose(transpose(X,-5) ,4) +transpose(X,7) ) |transpose(arpeggio(transpose(shuffle(X) ,4) ) ,-5) ) ,7) ) ,12) ) ,7) ) ) ,4) ) +transpose(((transpose(transpose((((echo(((((((transpose(X,4) +transpose(transpose(X,4) ,7) ) |transpose(((((X+X) |X) +transpose(arpeggio(X) ,4) ) |transpose((X|(X|X) ) ,-5) ) ,-7) ) +transpose(((((transpose(transpose(X,-5) ,-5) +transpose(((shuffle(X) +transpose(shuffle(X) ,4) ) +transpose(transpose(X,4) ,7) ) ,12) ) +transpose((X+(X+transpose((X+X) ,12) ) ) ,4) ) +transpose(((X+X) |(X|X) ) ,7) ) +((((step(X,12) +transpose(X,12) ) +transpose(transpose(X,4) ,7) ) |((X+transpose(X,7) ) +(X|X) ) ) +transpose(X,7) ) ) ,4) ) +transpose(echo(step(echo((X+X) ,4,6) ,12) ,4,6) ,7) ) +transpose((echo(shuffle(transpose(X,4) ) ,4,6) +echo(step(transpose(((X+transpose(X,7) ) +transpose(X,12) ) ,-7) ,12) ,4,6) ) ,7) ) +transpose(transpose(transpose((transpose(echo(step(X,12) ,4,6) ,-7) +(((X|X) +transpose(((X+X) +transpose(X,-7) ) ,4) ) +transpose(X,7) ) ) ,-7) ,4) ,7) ) ,4,6) +transpose(transpose(arpeggio(((arpeggio((echo(X,4,6) |(X|X) ) ) +((arpeggio(X) |transpose(X,-7) ) +arpeggio(arpeggio(transpose(X,4) ) ) ) ) |(step(transpose(shuffle(X) ,-5) ,12) +(transpose(X,-7) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ,12) ) ) ) ) ,-7) ,12) ) +transpose(step(transpose(transpose(((transpose((transpose((X+transpose(X,12) ) ,-5) +transpose(X,-5) ) ,-7) +transpose(X,-7) ) +transpose(echo(transpose(X,-5) ,4,6) ,7) ) ,-7) ,4) ,12) ,4) ) +transpose(((((transpose((transpose(shuffle(X) ,-5) +transpose(shuffle(arpeggio(X) ) ,7) ) ,-7) |transpose((((transpose((X+transpose(X,-5) ) ,4) +(X+transpose((X+transpose(transpose(X,-7) ,12) ) ,7) ) ) +transpose((transpose(X,-5) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ,-7) ) ,4) ) +transpose((((arpeggio(X) |arpeggio(X) ) +transpose((step(X,12) |(X+(X+X) ) ) ,4) ) +transpose(transpose((X+X) ,4) ,7) ) ,7) ) ,-5) ) +transpose(((transpose((echo(((X|((X+transpose(X,4) ) +transpose(X,7) ) ) +X) ,4,6) +arpeggio(transpose(X,-7) ) ) ,-5) +((step((X+transpose(transpose(X,-5) ,7) ) ,12) +transpose((arpeggio(arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) ) +(((X+transpose(X,12) ) +transpose(transpose(X,-7) ,7) ) |transpose(transpose(X,4) ,-5) ) ) ,4) ) +transpose((((arpeggio((X+transpose(X,12) ) ) +transpose(echo(X,4,6) ,4) ) +transpose(arpeggio(transpose(X,-5) ) ,7) ) +transpose((transpose((X|X) ,4) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ,7) ) ,7) ) ,7) ) ) +(transpose(transpose((X+transpose(X,12) ) ,-7) ,-7) +(((X+transpose(X,4) ) +transpose((X+transpose(X,7) ) ,7) ) +(step(X,12) +(X+transpose(transpose(X,4) ,12) ) ) ) ) ) ,4) ) +transpose(((((((((X|(transpose(X,-7) +transpose(X,-5) ) ) +transpose((((X|(X+transpose(X,7) ) ) +transpose(arpeggio(shuffle(X) ) ,4) ) +transpose((((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) +transpose(step(transpose(X,-5) ,12) ,4) ) +transpose(transpose((X+transpose(X,7) ) ,-5) ,7) ) ,7) ) ,7) ) +transpose(((transpose(transpose(X,4) ,4) +transpose(X,-5) ) +transpose(((arpeggio(X) +X) |((X+transpose(X,12) ) |(X+X) ) ) ,7) ) ,4) ) +transpose(transpose((transpose(arpeggio(X) ,-5) +(X|X) ) ,-5) ,7) ) +step(transpose(X,-5) ,12) ) +step(transpose(transpose(X,-5) ,4) ,12) ) +transpose(transpose(transpose((transpose(X,4) +transpose((X+transpose(X,7) ) ,12) ) ,-7) ,-7) ,4) ) +transpose((arpeggio(transpose((((transpose((X+transpose(X,7) ) ,-5) +transpose(X,-7) ) |(X+transpose(X,12) ) ) +transpose(transpose((((X|X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(X,7) ) ,4) ,7) ) ,4) ) +transpose((((echo(X,4,6) +transpose(X,4) ) +transpose(step(X,12) ,7) ) +transpose(((transpose(X,4) |transpose(X,-7) ) +(X+transpose(transpose(X,-7) ,12) ) ) ,7) ) ,-5) ) ,7) ) ,7) ) +transpose((transpose(step(arpeggio(transpose(step((X+((transpose(X,-5) +transpose(transpose(X,4) ,4) ) +transpose(arpeggio(X) ,7) ) ) ,12) ,-7) ) ,12) ,-5) +transpose(arpeggio(transpose((echo(echo(((shuffle(X) +transpose(arpeggio(X) ,7) ) |(transpose(X,4) +transpose(((X+X) |X) ,7) ) ) ,4,6) ,4,6) +transpose((transpose(X,-5) +transpose(((transpose(X,-7) |step(X,12) ) +transpose(arpeggio(X) ,4) ) ,12) ) ,12) ) ,4) ) ,12) ) ,12) ) ,7) ) ,4) ,-5) +transpose(transpose(echo(((echo(shuffle(transpose(((transpose(transpose(arpeggio(X) ,-7) ,-7) +transpose(shuffle(X) ,12) ) +transpose(((step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) +transpose(shuffle(X) ,4) ) +transpose((transpose(X,4) +transpose(X,12) ) ,7) ) ,7) ) ,-7) ) ,4,6) +transpose(echo(((echo(transpose(transpose(((X|(X+X) ) |shuffle(echo(X,4,6) ) ) ,4) ,-5) ,4,6) +transpose(transpose(transpose(echo((transpose((X|X) ,-5) |(step(X,12) +transpose((X|X) ,12) ) ) ,4,6) ,4) ,-5) ,7) ) +transpose(transpose((((((transpose(step((X+transpose((X+transpose(X,7) ) ,7) ) ,12) ,-7) +transpose(arpeggio(((transpose(X,-5) +transpose((X+X) ,4) ) +transpose(transpose(X,-5) ,7) ) ) ,4) ) +transpose(((transpose(X,-7) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) |(X+transpose(echo(X,4,6) ,12) ) ) ,7) ) +transpose(((((X+transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) |(step(X,12) |X) ) +transpose(transpose((X+transpose(X,7) ) ,4) ,7) ) ,4) ) +transpose((((X|X) |(step(shuffle(X) ,12) +transpose((X|X) ,12) ) ) +transpose((X+transpose(X,7) ) ,7) ) ,7) ) +transpose(transpose(X,-5) ,7) ) ,-5) ,7) ) ,4,6) ,4) ) +transpose(((((((((X+transpose((X+transpose(X,7) ) ,4) ) +transpose((X|X) ,7) ) +(X+X) ) +transpose(transpose(transpose(X,4) ,4) ,4) ) +transpose(step(echo(transpose(transpose(X,4) ,-5) ,4,6) ,12) ,7) ) +transpose(echo((transpose(((((X+X) +transpose(transpose(X,-7) ,4) ) +transpose(transpose(X,-5) ,7) ) +transpose(echo(X,4,6) ,-5) ) ,-7) |transpose(transpose((transpose(X,-5) +((X+transpose(X,4) ) +transpose(X,7) ) ) ,-5) ,-7) ) ,4,6) ,4) ) +transpose(((transpose((transpose(X,4) |((transpose(step(X,12) ,-5) +transpose(arpeggio(X) ,4) ) +transpose((X+transpose((X|X) ,7) ) ,7) ) ) ,4) +transpose(transpose(transpose((((X+X) +transpose(arpeggio(X) ,4) ) +transpose(transpose(X,-5) ,7) ) ,-5) ,-7) ,7) ) |((((X+transpose(X,12) ) +transpose(step(transpose(transpose(transpose(transpose(X,4) ,-5) ,-7) ,4) ,12) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) |arpeggio(transpose(X,4) ) ) ,7) ) +step(transpose(transpose(echo((arpeggio(X) +transpose(transpose(X,4) ,7) ) ,4,6) ,-7) ,4) ,12) ) ) ,7) ) |transpose(((((shuffle(transpose(X,-7) ) +(((X+X) +arpeggio(X) ) +transpose((X+X) ,-5) ) ) |((((X+transpose((X+transpose((echo(X,4,6) |(X+transpose(X,7) ) ) ,12) ) ,12) ) +transpose(((step(X,12) +transpose((transpose(X,-7) |transpose(X,4) ) ,4) ) +transpose(transpose(X,-7) ,7) ) ,4) ) +transpose(arpeggio(transpose((transpose(X,-5) +transpose(shuffle(X) ,7) ) ,-5) ) ,7) ) +transpose((arpeggio(transpose(X,4) ) +transpose(transpose(X,-7) ,4) ) ,12) ) ) +transpose(echo(transpose(((transpose(shuffle(X) ,4) +transpose((X+X) ,4) ) +transpose(((X+X) +transpose(X,12) ) ,7) ) ,4) ,4,6) ,4) ) +transpose((transpose(shuffle(((X+X) +(X+X) ) ) ,4) +transpose(echo((((X+transpose(X,12) ) +transpose((X+X) ,4) ) +transpose(X,7) ) ,4,6) ,7) ) ,7) ) ,4) ) ,7) ) ,4,6) ,-7) ,4) ) +transpose(transpose((transpose(transpose((echo(transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +(((X+transpose(X,12) ) +transpose(X,-5) ) +transpose(X,7) ) ) +transpose((X|echo((transpose(X,-7) |X) ,4,6) ) ,12) ) ,-5) ,4,6) |transpose(((transpose(step(shuffle(X) ,12) ,-5) +transpose((((((X+transpose(transpose(X,-7) ,7) ) +transpose(echo((X+transpose(X,7) ) ,4,6) ,4) ) +transpose(X,7) ) |echo(shuffle(X) ,4,6) ) +shuffle(((((X+transpose(X,7) ) +transpose(transpose(X,-7) ,7) ) +transpose(arpeggio(((X|X) +step((X|X) ,12) ) ) ,4) ) +transpose(((shuffle(X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(transpose(X,-7) ,7) ) ,7) ) ) ) ,4) ) +transpose(((step((((transpose((X+X) ,-5) +transpose(X,7) ) +(X+echo(X,4,6) ) ) |transpose(transpose(transpose((X+transpose(X,12) ) ,4) ,4) ,4) ) ,12) +transpose(echo(transpose(step(transpose(X,4) ,12) ,4) ,4,6) ,4) ) +transpose(transpose(shuffle((((X+X) +transpose(transpose(X,-7) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ) ,-5) ,7) ) ,7) ) ,4) ) ,4) ,-7) +transpose(step(((step(((transpose(X,4) +transpose(arpeggio((step(transpose(X,-7) ,12) +transpose((echo(X,4,6) +transpose(X,7) ) ,7) ) ) ,4) ) +transpose((((step(transpose((X+X) ,-5) ,12) +transpose((((X|X) +transpose(step(X,12) ,7) ) |X) ,4) ) +transpose(echo(transpose(X,-5) ,4,6) ,7) ) +transpose((transpose(X,4) +(transpose(X,-7) +transpose(echo(X,4,6) ,12) ) ) ,12) ) ,7) ) ,12) +transpose((transpose(X,-7) |((transpose(transpose(shuffle(transpose(X,4) ) ,-5) ,4) +transpose(((transpose(X,-5) +transpose(shuffle(X) ,12) ) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,4) ) ,-5) ) +transpose(transpose(transpose(((((transpose(X,-5) +transpose(X,4) ) +transpose(X,7) ) +transpose(arpeggio(arpeggio(X) ) ,12) ) |transpose(transpose(X,4) ,4) ) ,-5) ,-5) ,12) ) ) ,7) ) |(echo(((echo((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) +transpose(X,12) ) ,4,6) +transpose((transpose(transpose(X,4) ,-7) +transpose(((X+X) +transpose(transpose((X|X) ,-5) ,12) ) ,7) ) ,12) ) +transpose(echo(transpose((transpose(X,-5) +transpose(X,12) ) ,-7) ,4,6) ,12) ) ,4,6) |transpose((transpose((transpose(X,4) +transpose(step(X,12) ,12) ) ,-7) +transpose(echo((step(shuffle(X) ,12) +step(shuffle(X) ,12) ) ,4,6) ,4) ) ,-7) ) ) ,12) ,7) ) ,-5) ,7) ) ,7) ) ,12) ) ,4)
random seed used was 231341508

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