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:
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After 20 generations the expression "X" became this:
(shuffle((transpose(transpose(transpose((((shuffle(arpeggio(transpose(transpose(X,-5) ,-7) ) ) +transpose(((((shuffle(transpose(X,-5) ) +transpose((X+transpose(X,7) ) ,12) ) |(X+X) ) +transpose(echo(arpeggio(X) ,4,6) ,4) ) |transpose(transpose((((X+transpose(X,12) ) +transpose(X,4) ) +transpose(shuffle(X) ,7) ) ,4) ,4) ) ,12) ) +transpose(((transpose(arpeggio((X|transpose(step(X,12) ,4) ) ) ,-5) |((transpose(arpeggio(transpose(step(X,12) ,-5) ) ,4) +transpose(transpose((transpose(transpose(X,-7) ,-5) +transpose(transpose(((X|X) +arpeggio(X) ) ,4) ,12) ) ,-7) ,4) ) +transpose((((((shuffle(X) +transpose((X+transpose(X,12) ) ,4) ) +transpose(X,7) ) |echo(transpose(X,-7) ,4,6) ) +transpose(step(arpeggio(step(X,12) ) ,12) ,7) ) +echo((X|(((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose(X,4) ,12) ) ) ,4,6) ) ,7) ) ) +transpose((transpose((X+transpose((X+X) ,7) ) ,-7) +echo((transpose(X,4) +transpose(X,-7) ) ,4,6) ) ,12) ) ,7) ) +transpose(step((step((transpose(X,-5) +transpose(echo(X,4,6) ,7) ) ,12) |shuffle(((((X+transpose(X,7) ) +transpose(step(X,12) ,12) ) +transpose(echo(X,4,6) ,4) ) +transpose(transpose(step(X,12) ,4) ,7) ) ) ) ,12) ,-7) ) ,-7) ,4) ,-5) |arpeggio(transpose((((((transpose((X+echo((X+transpose(X,7) ) ,4,6) ) ,-5) +transpose(transpose(transpose(echo(shuffle((X|X) ) ,4,6) ,-5) ,4) ,7) ) +transpose(echo(transpose((echo((X+transpose(X,7) ) ,4,6) +transpose(echo(X,4,6) ,7) ) ,-7) ,4,6) ,4) ) +transpose((step(transpose((X|X) ,-5) ,12) +transpose((transpose((X|X) ,4) +transpose((step((X+transpose(X,12) ) ,12) +transpose((X+transpose(X,7) ) ,4) ) ,7) ) ,-5) ) ,7) ) |transpose(transpose((transpose(transpose(step(transpose((X|X) ,-5) ,12) ,-7) ,-5) +transpose((transpose(transpose(X,-5) ,-7) +transpose(transpose(transpose(arpeggio(X) ,-5) ,-7) ,12) ) ,12) ) ,4) ,-7) ) +transpose((transpose(transpose(((X+shuffle(X) ) +transpose(X,-7) ) ,-7) ,4) |(step(transpose(step(X,12) ,4) ,12) +transpose(echo((((X+transpose(X,4) ) +transpose(X,7) ) +(X+transpose(X,7) ) ) ,4,6) ,7) ) ) ,4) ) ,-5) ) ) ) |(((transpose(((transpose(transpose((shuffle(echo(transpose((echo((X|(X+transpose(X,7) ) ) ,4,6) +transpose((X+transpose(((X|X) +transpose(X,4) ) ,7) ) ,12) ) ,4) ,4,6) ) +transpose(transpose(((X+transpose(X,12) ) +((X|X) +transpose((((X+X) +echo(X,4,6) ) +transpose(transpose(transpose(X,-5) ,4) ,12) ) ,7) ) ) ,-5) ,12) ) ,4) ,4) |((((((X+(X+(X+transpose(X,12) ) ) ) +transpose(X,4) ) +transpose((X+transpose(X,12) ) ,-7) ) +transpose(transpose(((echo(X,4,6) +transpose((X+transpose(X,12) ) ,12) ) +transpose(X,12) ) ,4) ,12) ) +(transpose(((arpeggio(((X+transpose(X,12) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ) +transpose(step(transpose(X,-5) ,12) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) |transpose(X,4) ) ,7) ) ,-5) +transpose(shuffle(transpose(((X+transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,-7) ) ,12) ) ) +transpose((transpose((((X+transpose((X|X) ,4) ) +transpose(echo(X,4,6) ,7) ) |(((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,12) ) ) ,-7) +transpose(((transpose(arpeggio(transpose(X,-7) ) ,-7) +transpose((transpose(X,-7) |((transpose((X|X) ,-7) +transpose(X,4) ) +transpose(arpeggio((X|X) ) ,7) ) ) ,12) ) +transpose((step(transpose(step(step(X,12) ,12) ,-5) ,12) |((transpose(X,-5) +transpose(X,4) ) +transpose((shuffle(X) +(X+transpose(X,7) ) ) ,7) ) ) ,7) ) ,12) ) ,-5) ) ) +(step(echo(arpeggio(((transpose(shuffle(X) ,-5) +transpose(X,-7) ) +((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X|X) ,7) ) +X) ) ) ,4,6) ,12) |(((transpose((transpose((X+transpose(X,7) ) ,4) +transpose(echo(X,4,6) ,7) ) ,4) |echo(transpose(X,4) ,4,6) ) +transpose(shuffle((echo(((transpose(X,-5) +transpose(echo(X,4,6) ,4) ) +transpose(transpose(X,4) ,7) ) ,4,6) |(X+X) ) ) ,4) ) +transpose(transpose(transpose(transpose(X,-5) ,4) ,-7) ,7) ) ) ) ,-7) +transpose(arpeggio((echo(shuffle((step((X|transpose(transpose(X,-7) ,-7) ) ,12) +(((transpose((step(transpose(transpose(X,-5) ,4) ,12) +transpose(transpose(((X+transpose(X,12) ) |X) ,-5) ,7) ) ,-5) +(echo(transpose(transpose(step(X,12) ,-7) ,-7) ,4,6) +transpose(X,-7) ) ) +(step(((shuffle(X) +transpose(X,12) ) +(X+transpose(arpeggio(X) ,12) ) ) ,12) +transpose((transpose(((transpose((X+X) ,4) +transpose((((X+transpose(X,12) ) +transpose(echo(X,4,6) ,4) ) +transpose(arpeggio(X) ,7) ) ,4) ) +transpose((X|X) ,7) ) ,4) +transpose((echo(((step(X,12) +transpose((X+X) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,4,6) +transpose((transpose(echo((X|X) ,4,6) ,4) +X) ,7) ) ,7) ) ,7) ) ) +transpose(step((((((arpeggio(shuffle(X) ) +(X+X) ) +transpose((((shuffle(X) +(X+transpose(X,12) ) ) +transpose((X+transpose(X,7) ) ,4) ) +transpose((X+X) ,7) ) ,12) ) +transpose(transpose(arpeggio(step((X+transpose(X,7) ) ,12) ) ,-7) ,4) ) +transpose(transpose(transpose(transpose(transpose(X,4) ,-7) ,-5) ,-7) ,7) ) +transpose(X,-7) ) ,12) ,12) ) ) ) ,4,6) |echo(((transpose(transpose((shuffle(((X+transpose(transpose(X,4) ,-5) ) +(((step(X,12) +transpose((echo(X,4,6) +transpose(X,7) ) ,4) ) +transpose(transpose(X,4) ,7) ) +transpose(step(X,12) ,4) ) ) ) |transpose((echo(X,4,6) +transpose(transpose(X,-5) ,12) ) ,4) ) ,-7) ,4) +transpose(echo(shuffle(transpose((((((X+transpose(X,4) ) +transpose(X,7) ) |X) +(X+transpose(X,4) ) ) +transpose((X|X) ,7) ) ,4) ) ,4,6) ,4) ) +transpose(shuffle((transpose(arpeggio((X+X) ) ,-7) |echo((transpose((X+transpose((X|X) ,12) ) ,-5) +echo(transpose(transpose(X,-7) ,4) ,4,6) ) ,4,6) ) ) ,7) ) ,4,6) ) ) ,7) ) +transpose((shuffle(transpose(shuffle(((((((shuffle((transpose(X,-7) |X) ) +transpose(X,-5) ) +transpose((transpose((X|X) ,-7) |transpose((transpose(X,-5) +transpose(echo(X,4,6) ,7) ) ,4) ) ,12) ) +(((X+X) +transpose(transpose(X,4) ,7) ) +(X+X) ) ) |(((((((step(X,12) +shuffle((X+X) ) ) +transpose((((X+X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(X,7) ) ,4) ) +transpose(((X+transpose((X+transpose(X,7) ) ,7) ) |(step(X,12) +(X+X) ) ) ,7) ) +transpose((transpose((transpose(X,4) +transpose(X,7) ) ,4) +((arpeggio(X) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ) ,4) ) +transpose(transpose((X+transpose(X,12) ) ,-7) ,7) ) +((transpose(transpose((echo(X,4,6) +echo(X,4,6) ) ,-7) ,-7) +transpose(((((X+transpose(X,7) ) +transpose(step(transpose(X,-5) ,12) ,7) ) +transpose(transpose((transpose(X,4) |(X+transpose(X,12) ) ) ,-5) ,4) ) +transpose((((X+transpose(X,12) ) +transpose((X|X) ,4) ) +transpose(X,7) ) ,7) ) ,4) ) +transpose(transpose(step(X,12) ,-7) ,7) ) ) |((X|(X+X) ) +transpose(transpose(X,-5) ,12) ) ) ) +transpose((transpose(transpose((transpose(transpose(((arpeggio(X) +transpose(transpose(X,-5) ,4) ) +transpose(X,7) ) ,-5) ,4) +transpose(step((transpose(transpose(X,-5) ,4) +transpose(transpose(X,-7) ,7) ) ,12) ,12) ) ,-7) ,4) +transpose((((shuffle(X) |step(X,12) ) +transpose(transpose(transpose(step((X+X) ,12) ,-7) ,-5) ,12) ) |step(step((((X+transpose(X,4) ) +transpose(X,7) ) |step(transpose(X,4) ,12) ) ,12) ,12) ) ,7) ) ,4) ) +transpose(transpose(transpose(((transpose(echo(X,4,6) ,4) +(X+(X|X) ) ) |((X+transpose(((transpose(X,-7) +transpose((X+transpose(X,12) ) ,4) ) +transpose(X,7) ) ,12) ) +transpose(step(transpose((X+transpose(X,12) ) ,-7) ,12) ,12) ) ) ,-7) ,4) ,7) ) ) ,-7) ) +transpose((((echo((transpose(((shuffle(((transpose(arpeggio(transpose(transpose(step(X,12) ,-7) ,-7) ) ,-7) +transpose(((((transpose(X,4) +transpose(step((X+transpose((X|X) ,12) ) ,12) ,12) ) +transpose(transpose(((X+transpose(X,7) ) +transpose(((X+X) +transpose(transpose(X,4) ,7) ) ,12) ) ,4) ,4) ) +transpose(step((X+X) ,12) ,7) ) +(((transpose(X,-5) +transpose(X,4) ) |X) +transpose((((X+transpose((((X+X) +transpose((X+transpose(X,7) ) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,12) ) |(transpose(X,-7) +transpose(X,-7) ) ) +(transpose((X+transpose(X,7) ) ,-5) |transpose((transpose(X,-7) +transpose(transpose(X,4) ,12) ) ,-7) ) ) ,12) ) ) ,4) ) +transpose((transpose(((step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) +transpose(((X+X) +transpose(X,7) ) ,4) ) +transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,7) ) ,4) |(transpose(arpeggio(arpeggio(X) ) ,-7) |((shuffle(((X+X) |arpeggio(X) ) ) +transpose(((X+transpose(X,12) ) +transpose(transpose(X,-5) ,12) ) ,12) ) |(step(echo(X,4,6) ,12) +transpose(X,-5) ) ) ) ) ,7) ) ) +transpose((transpose((X|((transpose(X,-5) +transpose(X,-7) ) |(X+transpose(X,12) ) ) ) ,-7) |arpeggio(transpose(transpose(X,4) ,4) ) ) ,-5) ) +((arpeggio(shuffle((X+(X|X) ) ) ) +transpose(echo(transpose(X,4) ,4,6) ,7) ) |((((transpose(((X+transpose((arpeggio(X) +X) ,4) ) +transpose(transpose((X|X) ,4) ,7) ) ,-7) |shuffle((transpose(echo(X,4,6) ,4) +X) ) ) |shuffle((((X+((X+transpose(X,4) ) +transpose(X,7) ) ) |((X+transpose(X,12) ) |(X+transpose(X,4) ) ) ) +(transpose(X,4) +transpose(arpeggio(X) ,7) ) ) ) ) +transpose((echo(((X+transpose(X,12) ) +transpose((X|X) ,7) ) ,4,6) +transpose(X,12) ) ,4) ) +transpose((((arpeggio((X+transpose(X,12) ) ) |(((X+transpose(X,12) ) +transpose(transpose(X,4) ,12) ) |((((X+X) +transpose(arpeggio(X) ,4) ) +transpose(transpose(X,4) ,7) ) +echo(X,4,6) ) ) ) |echo(transpose((X+transpose(X,7) ) ,4) ,4,6) ) +transpose(arpeggio(((((X+transpose(X,7) ) +transpose(X,7) ) |(transpose(X,-7) |(X+X) ) ) +(transpose(step((X+transpose(X,12) ) ,12) ,-5) |echo(transpose(X,-7) ,4,6) ) ) ) ,7) ) ,7) ) ) ) ,-7) +step(transpose(((arpeggio(echo(transpose(X,-5) ,4,6) ) +transpose(transpose(((transpose((X+X) ,-5) +transpose(transpose(X,4) ,12) ) +transpose(((step(X,12) +transpose((X+transpose(X,7) ) ,7) ) +echo(transpose(X,4) ,4,6) ) ,7) ) ,4) ,7) ) +((transpose(step(shuffle(X) ,12) ,-7) +transpose(((((step(X,12) +transpose(shuffle(X) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) |echo(X,4,6) ) +transpose(shuffle(transpose(X,4) ) ,7) ) ,4) ) +transpose((((((X+transpose(X,7) ) +transpose(arpeggio(X) ,4) ) +transpose(X,7) ) |X) +(X+transpose(shuffle(X) ,7) ) ) ,7) ) ) ,-5) ,12) ) ,4,6) +transpose(arpeggio(transpose(((transpose(transpose((arpeggio(transpose(arpeggio(X) ,4) ) +(transpose(arpeggio(X) ,-5) |(transpose(X,-5) +transpose(X,-5) ) ) ) ,4) ,-7) +transpose((shuffle(echo(transpose(((X+transpose((X+X) ,4) ) +transpose(X,7) ) ,-7) ,4,6) ) +transpose((step(arpeggio(X) ,12) +transpose((((X|X) +transpose((step(X,12) +(X+X) ) ,4) ) +transpose(step(X,12) ,7) ) ,12) ) ,-5) ) ,4) ) +transpose(transpose(transpose(shuffle(step((X|(X+X) ) ,12) ) ,-5) ,4) ,7) ) ,-7) ) ,12) ) +((transpose(transpose((arpeggio((transpose((X|(arpeggio((X|X) ) +transpose(X,12) ) ) ,4) +(transpose(transpose((X|X) ,-5) ,-7) +((arpeggio(echo(X,4,6) ) +X) +transpose((X|X) ,-7) ) ) ) ) +transpose(transpose(shuffle(step(transpose(transpose(step(X,12) ,-5) ,-7) ,12) ) ,-7) ,12) ) ,-5) ,-5) +transpose(step(transpose(shuffle(echo(step((((transpose(X,-7) +X) +transpose(transpose(X,4) ,12) ) +transpose(transpose((arpeggio(X) +transpose(transpose(X,-7) ,12) ) ,-5) ,12) ) ,12) ,4,6) ) ,4) ,12) ,12) ) +transpose(arpeggio(((transpose(echo((((transpose(echo((X|X) ,4,6) ,4) |X) +transpose(transpose(X,4) ,4) ) +transpose(transpose(((X+X) |X) ,4) ,7) ) ,4,6) ,-5) +((((((X|X) +transpose(transpose((X+transpose(X,12) ) ,-5) ,4) ) +transpose((transpose(X,-7) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,7) ) +transpose(transpose((X+X) ,-5) ,12) ) +transpose(echo(transpose((X+X) ,-7) ,4,6) ,12) ) +transpose(transpose((((X+transpose(X,12) ) +transpose(echo(X,4,6) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,-5) ,12) ) ) +(arpeggio(arpeggio(shuffle((shuffle(X) +transpose(X,7) ) ) ) ) +transpose(echo((((shuffle(X) +transpose(transpose((X+transpose(X,7) ) ,-5) ,4) ) +transpose(X,7) ) +transpose(shuffle((X|X) ) ,12) ) ,4,6) ,4) ) ) ) ,7) ) ) |arpeggio(transpose(echo(echo((((transpose(transpose(arpeggio((transpose(X,4) +transpose((X+transpose(X,7) ) ,7) ) ) ,4) ,-5) +transpose(((arpeggio((((((shuffle(transpose(X,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(step(X,12) ,12) ) ,7) ) |transpose((transpose(echo(X,4,6) ,-7) +transpose(transpose(transpose(X,4) ,-7) ,7) ) ,4) ) +transpose(echo((X|X) ,4,6) ,4) ) +transpose((((X+transpose((X+X) ,12) ) |(transpose(X,4) +transpose((X|X) ,7) ) ) |step(X,12) ) ,7) ) +arpeggio(echo(transpose((X+transpose(X,12) ) ,4) ,4,6) ) ) ) +transpose(transpose(transpose((step((X+X) ,12) +transpose(shuffle(X) ,12) ) ,-7) ,-5) ,4) ) +transpose((step(transpose((transpose(X,-7) +transpose(((transpose(step(X,12) ,-5) +transpose((((X+transpose(X,7) ) +transpose(X,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,4) ) +transpose(shuffle((X+X) ) ,7) ) ,7) ) ,-5) ,12) +transpose(transpose(((X+X) +X) ,4) ,7) ) ,7) ) ,4) ) +transpose((transpose(((arpeggio(transpose(transpose(transpose(X,4) ,-7) ,-7) ) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) |(X|X) ) +transpose(X,-5) ) ,4) ) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose((X|X) ,7) ) ,7) ) ,-7) +transpose(step(transpose(transpose((X+transpose(X,12) ) ,-7) ,-7) ,12) ,7) ) ,7) ) +((echo((echo((echo(((X|X) +(X+transpose(X,12) ) ) ,4,6) +transpose(echo((step(echo(X,4,6) ,12) |(X|(((X+transpose(X,7) ) +transpose(X,4) ) +transpose((X+transpose(X,12) ) ,7) ) ) ) ,4,6) ,12) ) ,4,6) +transpose(arpeggio(((transpose(X,-5) |arpeggio(transpose(X,-5) ) ) +transpose(((X|(transpose(X,4) +transpose((X+X) ,12) ) ) +transpose(step(X,12) ,12) ) ,12) ) ) ,7) ) ,4,6) +transpose((((transpose(transpose(X,-7) ,-5) |step(X,12) ) +transpose(echo(transpose(X,-7) ,4,6) ,12) ) |shuffle((transpose(transpose(transpose(X,-5) ,-5) ,4) |step(arpeggio(((X+(X+X) ) +X) ) ,12) ) ) ) ,4) ) +transpose(((transpose(transpose(transpose((X+X) ,-5) ,4) ,-7) |transpose(((transpose(X,-5) +transpose(transpose(X,4) ,4) ) +transpose((transpose(X,-5) +transpose(((X+transpose(X,7) ) +transpose(X,7) ) ,7) ) ,7) ) ,-5) ) +transpose((X|(((X+X) +transpose(step(X,12) ,7) ) +(X+transpose(X,12) ) ) ) ,7) ) ,7) ) ) ,4,6) ,4,6) ,4) ) ) ,12) ) ,4) ) +transpose(transpose(transpose(((transpose(transpose(transpose((transpose(X,-5) |shuffle(transpose(X,-5) ) ) ,-5) ,-5) ,4) +transpose((transpose(arpeggio((((transpose(((X|X) +transpose((X+X) ,12) ) ,-5) +transpose(transpose(((echo((X+X) ,4,6) +transpose(transpose(((X+transpose(transpose(X,-7) ,4) ) +transpose(X,7) ) ,-5) ,4) ) +transpose(transpose(X,-5) ,7) ) ,-5) ,12) ) +transpose(step(((shuffle(transpose(transpose(X,-5) ,4) ) +transpose((X+transpose(X,7) ) ,4) ) +transpose(shuffle((arpeggio(X) +((X+transpose(X,7) ) +(X+transpose(X,7) ) ) ) ) ,7) ) ,12) ,4) ) +transpose((((transpose(X,-7) |(step(X,12) |shuffle(X) ) ) +((arpeggio(transpose(X,4) ) +transpose((X+X) ,4) ) +transpose(shuffle(transpose(X,-7) ) ,7) ) ) +transpose((X+transpose(arpeggio((X|X) ) ,7) ) ,7) ) ,7) ) ) ,-5) |(transpose(((arpeggio(transpose((transpose((transpose(X,-5) |X) ,-5) +transpose(X,7) ) ,-5) ) +transpose(transpose(arpeggio(transpose(transpose(((X|X) +(X+transpose(X,7) ) ) ,4) ,-5) ) ,4) ,4) ) +transpose(transpose(echo(X,4,6) ,4) ,7) ) ,-7) +transpose(echo(transpose(((((X|transpose(X,-5) ) +transpose(transpose(X,-5) ,7) ) |(arpeggio((X+X) ) +transpose(echo((X+X) ,4,6) ,12) ) ) |transpose(((X|X) |X) ,-7) ) ,-5) ,4,6) ,12) ) ) ,7) ) +transpose((shuffle((((step((transpose(shuffle((X|((X+transpose(X,4) ) +transpose(X,7) ) ) ) ,-7) +shuffle(transpose((X|X) ,-7) ) ) ,12) +transpose(transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,-5) ) +transpose(transpose((shuffle(X) |(X|X) ) ,4) ,7) ) ,-5) ,4) ) +transpose(((transpose(X,4) |echo(((X+transpose((X|X) ,4) ) +transpose((X|X) ,7) ) ,4,6) ) +transpose((shuffle((X+X) ) +transpose(X,7) ) ,12) ) ,7) ) |arpeggio(transpose(arpeggio(shuffle(transpose(arpeggio(X) ,4) ) ) ,-5) ) ) ) +transpose((((transpose((((((X+transpose(transpose(X,-7) ,4) ) +transpose(X,7) ) +transpose(step(X,12) ,12) ) +transpose((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) +(X+transpose(X,7) ) ) ,12) ) +transpose(transpose(transpose((X+transpose(X,7) ) ,-5) ,-5) ,12) ) ,-7) +transpose(echo(((((X+X) +transpose(arpeggio(X) ,12) ) +((X+transpose(X,7) ) +transpose(X,12) ) ) +arpeggio((arpeggio(X) +transpose(transpose(X,-7) ,12) ) ) ) ,4,6) ,12) ) |transpose(((X+transpose(echo(X,4,6) ,7) ) +transpose((X+transpose(X,12) ) ,7) ) ,-7) ) +step(step((shuffle(transpose((X+X) ,-5) ) +transpose(arpeggio((transpose(X,-7) +((X+transpose(X,4) ) +transpose(X,7) ) ) ) ,4) ) ,12) ,12) ) ,7) ) ,7) ) ,4) ,-7) ,7) ) )
random seed used was 137030414

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