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(transpose((X+transpose(X,12) ) ,4) ,4) |(transpose(transpose(X,-5) ,4) +transpose(step(X,12) ,12) ) ) +transpose((transpose(transpose(X,4) ,4) |transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,-5) ) ,4) ) +transpose(echo(((arpeggio(arpeggio((X|X) ) ) +transpose((step(transpose(X,-5) ,12) +((X+transpose(X,12) ) +transpose(X,7) ) ) ,12) ) +transpose(transpose(transpose(transpose((X|X) ,-5) ,-7) ,4) ,12) ) ,4,6) ,7) ) +transpose((echo(shuffle((transpose(transpose(arpeggio(transpose(X,-5) ) ,-5) ,-7) +transpose(shuffle(transpose((transpose(X,-7) +transpose(X,7) ) ,-5) ) ,12) ) ) ,4,6) +echo((transpose(echo(transpose(transpose((transpose(transpose(X,4) ,-5) +transpose(echo(X,4,6) ,12) ) ,4) ,-7) ,4,6) ,-5) +transpose((transpose(transpose(shuffle(X) ,-5) ,-5) +transpose((((step(X,12) +(X+X) ) |(X+arpeggio(X) ) ) +transpose(step(shuffle(X) ,12) ,4) ) ,7) ) ,-7) ) ,4,6) ) ,7) ) +shuffle(((step((step((X+X) ,12) +transpose((((X+transpose(X,12) ) +step(X,12) ) |shuffle(transpose(X,-5) ) ) ,12) ) ,12) |transpose((((X+transpose(X,7) ) +transpose(transpose(X,-7) ,7) ) +transpose(step(X,12) ,12) ) ,-7) ) |(((((shuffle(X) |((transpose(X,4) +transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) ) |(transpose(transpose(X,-7) ,-7) +transpose(echo(X,4,6) ,-5) ) ) +(((transpose(transpose(X,-7) ,-7) |transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) +transpose(echo(((X+transpose(transpose(X,4) ,12) ) |X) ,4,6) ,7) ) ) +transpose(((step((X+transpose(X,12) ) ,12) +transpose(transpose(step(X,12) ,-7) ,12) ) +transpose((transpose(transpose((X+X) ,4) ,-5) +transpose(step(X,12) ,7) ) ,12) ) ,4) ) +transpose((echo(X,4,6) |transpose(X,-5) ) ,7) ) ) ) ) |((((transpose(transpose((((((X+transpose(X,4) ) +transpose((X+X) ,4) ) +transpose(transpose(X,-5) ,7) ) +transpose((X+X) ,7) ) +transpose(((((X+transpose(X,7) ) +transpose(X,4) ) +transpose((X|X) ,7) ) +transpose(transpose(X,-7) ,12) ) ,7) ) ,4) ,-5) |transpose(arpeggio((transpose((X+(X+transpose(echo(X,4,6) ,12) ) ) ,-5) +(((X+X) +transpose(transpose(shuffle(X) ,4) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) ) ) ,4) ) +((transpose(transpose(transpose((X+transpose(X,7) ) ,4) ,4) ,-7) +transpose(transpose((((X|X) +transpose(transpose(X,-7) ,4) ) +transpose((X+X) ,7) ) ,4) ,4) ) |(((X+transpose((X+transpose(transpose(X,4) ,12) ) ,12) ) +transpose(transpose(X,4) ,7) ) +transpose((arpeggio((echo(X,4,6) +(X+transpose(X,12) ) ) ) +echo(echo((X+transpose(X,7) ) ,4,6) ,4,6) ) ,7) ) ) ) +transpose(transpose(transpose(((((X+transpose(X,7) ) +transpose(X,7) ) +transpose(X,-5) ) +transpose(X,-5) ) ,4) ,-7) ,12) ) +transpose(transpose(((transpose(X,-7) +transpose(step(X,12) ,12) ) |((X+transpose(X,-7) ) +transpose((echo(X,4,6) +transpose(X,12) ) ,7) ) ) ,4) ,-7) ) ) |((((transpose((transpose(transpose(transpose((X+transpose(arpeggio(X) ,7) ) ,-5) ,4) ,-5) +transpose((arpeggio((transpose(X,-7) +shuffle(arpeggio(X) ) ) ) |(step(((X+transpose(step(X,12) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,12) +echo(transpose(transpose(X,-7) ,-5) ,4,6) ) ) ,12) ) ,-5) +transpose((((shuffle(X) +transpose(((shuffle(transpose(((X+transpose(echo(X,4,6) ,4) ) +transpose(echo(X,4,6) ,7) ) ,4) ) +transpose(((X+transpose(X,7) ) +transpose(((step(X,12) +transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) ,12) ) ,-7) ) |transpose(transpose(X,-5) ,-5) ) ,4) ) +transpose(arpeggio(((arpeggio(arpeggio(X) ) +(step(transpose((X+X) ,4) ,12) |(transpose(X,-7) +X) ) ) +transpose((arpeggio(X) |(X+X) ) ,7) ) ) ,7) ) +arpeggio(transpose((transpose(arpeggio((transpose(X,-5) +transpose(transpose(X,-5) ,7) ) ) ,-7) +transpose(transpose(step(X,12) ,4) ,-5) ) ,-5) ) ) ,4) ) +transpose(transpose((((transpose(transpose((((X+transpose(transpose(X,4) ,7) ) +transpose(transpose(X,-5) ,7) ) +transpose((X+X) ,7) ) ,-5) ,-5) |step(((transpose(transpose((X+transpose(X,7) ) ,-7) ,-5) +arpeggio(transpose(transpose(X,4) ,4) ) ) +arpeggio(transpose(((X|X) +transpose((X|X) ,7) ) ,-7) ) ) ,12) ) +transpose(arpeggio((arpeggio(transpose(transpose((X+X) ,-7) ,4) ) |transpose(((step((transpose(transpose(X,-7) ,4) +X) ,12) +transpose((step(transpose(X,-7) ,12) +transpose(echo(transpose(X,4) ,4,6) ,4) ) ,4) ) +transpose(step(arpeggio(arpeggio(X) ) ,12) ,7) ) ,-7) ) ) ,4) ) +transpose(transpose(((shuffle((X|X) ) +transpose(transpose(X,4) ,-7) ) +arpeggio(transpose((((X+transpose(X,12) ) +transpose((X|X) ,4) ) +transpose((X+X) ,7) ) ,-5) ) ) ,-7) ,7) ) ,-7) ,7) ) +transpose((shuffle(transpose(((transpose(X,4) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ,4) ) +transpose((X+transpose(X,4) ) ,7) ) ,-7) ) +arpeggio(step(transpose(transpose((X+transpose(X,7) ) ,-7) ,-7) ,12) ) ) ,7) ) +(transpose((((transpose(((((X+transpose((X|X) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) +transpose((X|X) ,-7) ) +(transpose(X,4) |(X+transpose(X,12) ) ) ) ,4) |transpose(arpeggio(((X|X) +transpose(shuffle(X) ,12) ) ) ,-7) ) |transpose(echo(echo((X|X) ,4,6) ,4,6) ,4) ) +transpose(transpose(step((echo(X,4,6) |transpose(X,-5) ) ,12) ,4) ,7) ) ,4) +(transpose(((transpose(transpose(((((X+transpose(X,7) ) |transpose(X,-5) ) +(X+transpose(X,7) ) ) +X) ,4) ,4) +transpose((transpose(echo(X,4,6) ,-7) |transpose(((transpose(X,-5) +transpose(step(X,12) ,4) ) +transpose(X,7) ) ,4) ) ,4) ) +transpose((((transpose(X,-7) +transpose(transpose(X,-7) ,12) ) |((X|X) +transpose(X,7) ) ) |shuffle(((step(X,12) |(X|(X+transpose(X,7) ) ) ) +transpose((X|X) ,12) ) ) ) ,7) ) ,-5) +(transpose((((((X+transpose(X,4) ) +transpose(X,7) ) |X) |(transpose(X,4) +shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) ) ) +transpose((transpose(((X+transpose(X,12) ) |((transpose(X,-7) +transpose((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,7) ) +transpose(shuffle((transpose(X,4) |transpose(X,4) ) ) ,12) ) ) ,-7) +(((transpose(X,4) +transpose(((X+X) +transpose(X,-5) ) ,7) ) +transpose(shuffle(transpose(X,-5) ) ,4) ) +transpose(shuffle((X+transpose(X,4) ) ) ,7) ) ) ,12) ) ,-5) |(transpose(((transpose(X,-5) |shuffle(X) ) |(X+transpose(X,7) ) ) ,-7) +transpose(transpose(step(((step((X+transpose(X,12) ) ,12) +X) +(X|echo(X,4,6) ) ) ,12) ,-5) ,12) ) ) ) ) ) ) ,-5) +transpose(transpose(((shuffle(((shuffle((transpose(echo(transpose(echo(shuffle(echo(X,4,6) ) ,4,6) ,4) ,4,6) ,-5) +transpose(transpose(transpose((step(transpose(shuffle(X) ,-7) ,12) +transpose((X+X) ,7) ) ,4) ,4) ,12) ) ) |(step(((step(((transpose(X,-7) +transpose(echo(X,4,6) ,4) ) +transpose(transpose(X,-5) ,7) ) ,12) |echo(step(transpose(transpose(transpose(X,-5) ,4) ,-5) ,12) ,4,6) ) |arpeggio(((transpose((X+transpose(X,12) ) ,4) +transpose(echo((X+transpose(arpeggio(X) ,7) ) ,4,6) ,4) ) +transpose(echo(transpose(transpose(X,4) ,-7) ,4,6) ,7) ) ) ) ,12) +(transpose((((((X+transpose(echo(step(X,12) ,4,6) ,4) ) +transpose(X,7) ) +transpose(X,7) ) |(transpose(X,4) +(X+X) ) ) +transpose(((shuffle(((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(step(arpeggio(X) ,12) ,4) ) +transpose((((step(X,12) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) +transpose(transpose(X,-7) ,12) ) +transpose((transpose(X,-7) +transpose((X+transpose(X,12) ) ,7) ) ,12) ) ,7) ) ,12) ) ,-5) +transpose(((X+transpose(shuffle(arpeggio((X+X) ) ) ,12) ) |transpose(transpose(X,-5) ,4) ) ,7) ) ) ) |(transpose((((arpeggio((X+X) ) |((((transpose(transpose((X+transpose(X,7) ) ,4) ,-5) |step(X,12) ) +transpose((transpose(((transpose(X,-7) +transpose(X,4) ) +transpose(step(X,12) ,7) ) ,-7) +transpose(((((X+transpose(X,7) ) +transpose(X,12) ) +transpose(((echo(X,4,6) +transpose(echo(X,4,6) ,4) ) +transpose(X,7) ) ,4) ) +transpose((transpose(X,-7) +(X+X) ) ,7) ) ,7) ) ,7) ) +transpose(((shuffle(X) +transpose(echo(X,4,6) ,4) ) +transpose(step(transpose(X,4) ,12) ,7) ) ,4) ) +transpose(transpose(transpose(((transpose(transpose(X,4) ,-5) +transpose(((transpose(X,-7) +transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) ,4) ) +transpose(transpose(X,-5) ,7) ) ,-7) ,4) ,7) ) ) +transpose(transpose(echo(((transpose((X|X) ,-7) +transpose((transpose(X,-5) +transpose((X|X) ,7) ) ,4) ) +transpose(X,7) ) ,4,6) ,4) ,4) ) +transpose(arpeggio(((transpose(transpose(X,4) ,-5) +transpose(((X+transpose((X|X) ,12) ) |transpose(transpose(X,-7) ,-7) ) ,4) ) +transpose(((arpeggio(X) +(X+transpose(X,7) ) ) |transpose(X,-7) ) ,7) ) ) ,7) ) ,-5) +transpose(transpose(shuffle((X+(((X+X) +transpose(arpeggio(X) ,12) ) +transpose(step(arpeggio(X) ,12) ,7) ) ) ) ,-7) ,7) ) ) ) |((arpeggio(transpose(echo(transpose(transpose(transpose(transpose(((X+transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) ,-7) ,-5) ,-5) ,-5) ,4,6) ,4) ) +transpose((shuffle(transpose(transpose(((((X+X) +transpose(step(X,12) ,4) ) +transpose(transpose(transpose(X,-5) ,4) ,7) ) |X) ,-5) ,4) ) |(((((transpose((transpose(transpose((transpose(X,4) +transpose(echo(X,4,6) ,7) ) ,-5) ,4) +echo(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,4,6) ) ,4) +transpose(transpose((((X|X) |X) |arpeggio(transpose(transpose((X+X) ,-5) ,4) ) ) ,-5) ,4) ) +transpose(step((arpeggio(transpose((transpose(X,-7) +transpose(echo((X+transpose(X,12) ) ,4,6) ,12) ) ,4) ) +(arpeggio(step((X+X) ,12) ) +shuffle(((X+X) +transpose((X|X) ,7) ) ) ) ) ,12) ,7) ) +transpose(echo(transpose(((((transpose(transpose(X,4) ,-5) +arpeggio(((X+X) |X) ) ) +transpose(X,4) ) +transpose((transpose(((echo((X+X) ,4,6) |transpose(X,-7) ) +transpose((X+transpose((X|X) ,7) ) ,12) ) ,4) +transpose(echo((echo(transpose(X,-5) ,4,6) +transpose(step(transpose((X+transpose(X,7) ) ,-5) ,12) ,7) ) ,4,6) ,12) ) ,4) ) +transpose(arpeggio(((echo(arpeggio(transpose(step(X,12) ,-5) ) ,4,6) +transpose(((shuffle(X) |arpeggio(X) ) +transpose(transpose(transpose(X,-7) ,4) ,7) ) ,4) ) +transpose(transpose(transpose(transpose(X,4) ,-5) ,4) ,7) ) ) ,7) ) ,-7) ,4,6) ,4) ) +transpose((shuffle(step(echo(arpeggio(transpose(step(X,12) ,4) ) ,4,6) ,12) ) |(transpose(transpose(X,-5) ,-7) +transpose(transpose(X,-7) ,-5) ) ) ,7) ) +transpose(step(step(transpose(arpeggio(X) ,4) ,12) ,12) ,-7) ) ) ,4) ) +transpose(((transpose(((((X+transpose(X,12) ) |transpose(transpose(X,-7) ,-7) ) +transpose(transpose(((((((X+transpose(X,-5) ) +transpose(echo(X,4,6) ,4) ) +transpose(transpose(X,-5) ,7) ) +transpose(((X|X) +X) ,4) ) +transpose(transpose((X+transpose(X,12) ) ,4) ,7) ) +transpose(echo(((X+X) +transpose((X+X) ,12) ) ,4,6) ,-7) ) ,-7) ,7) ) |transpose(transpose(((transpose(transpose((shuffle(X) |transpose((X|X) ,4) ) ,4) ,-5) +transpose(transpose(((arpeggio((X|X) ) +transpose((arpeggio(arpeggio(X) ) |transpose((X+transpose(X,12) ) ,4) ) ,4) ) +transpose((((X+transpose(X,7) ) |transpose(arpeggio(X) ,-5) ) +transpose((((X+transpose((X+transpose(X,12) ) ,4) ) +transpose(X,7) ) +(X+transpose(X,-5) ) ) ,7) ) ,7) ) ,-5) ,7) ) +echo(((step(transpose(shuffle(echo(X,4,6) ) ,-5) ,12) +transpose(shuffle(transpose(transpose(shuffle(X) ,-7) ,-7) ) ,-5) ) |arpeggio(transpose((shuffle(echo(X,4,6) ) +transpose((step(X,12) +transpose(transpose(X,-7) ,12) ) ,12) ) ,-7) ) ) ,4,6) ) ,4) ,4) ) ,-5) +transpose(transpose(transpose(transpose(((transpose((transpose((arpeggio(X) +transpose(X,7) ) ,-7) +transpose(transpose(transpose((echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) +((X|X) +transpose(transpose(X,4) ,12) ) ) ,-5) ,-5) ,12) ) ,-5) |transpose(((arpeggio(transpose(echo((X+X) ,4,6) ,4) ) +transpose(((shuffle(transpose(X,-5) ) +transpose(((arpeggio(X) +transpose(arpeggio(X) ,4) ) +transpose(step(X,12) ,7) ) ,7) ) +transpose(shuffle(X) ,7) ) ,12) ) |transpose((transpose(transpose((X+transpose(X,12) ) ,4) ,-7) |transpose(transpose(((X+transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,4) ,4) ) ,-7) ) ,4) ) +transpose((transpose(((transpose(((X+transpose(transpose(X,4) ,4) ) +transpose(echo((X+transpose(X,7) ) ,4,6) ,7) ) ,4) +transpose(step(X,12) ,-5) ) +transpose(transpose(transpose((X+transpose(X,-5) ) ,-7) ,4) ,7) ) ,-7) +transpose(((arpeggio(transpose(arpeggio(((X|X) +transpose((X|X) ,12) ) ) ,4) ) +transpose(shuffle((transpose(echo(arpeggio(X) ,4,6) ,-5) +transpose(transpose((X+X) ,-5) ,12) ) ) ,4) ) +transpose(((X|X) |shuffle(shuffle(X) ) ) ,7) ) ,12) ) ,12) ) ,4) ,4) ,-7) ,4) ) +transpose(transpose((((transpose(step(step(echo((X+X) ,4,6) ,12) ,12) ,-7) +transpose(transpose((shuffle(transpose(shuffle(((X+transpose(X,7) ) +transpose(X,12) ) ) ,-7) ) +(step((X+transpose(X,-5) ) ,12) |((echo(X,4,6) |transpose(arpeggio(X) ,4) ) |transpose((((X+transpose(X,4) ) +transpose(X,7) ) |(X+transpose(X,12) ) ) ,-5) ) ) ) ,-5) ,12) ) +((transpose(X,-5) +transpose((arpeggio((X|X) ) |transpose(X,-7) ) ,12) ) |((echo(echo((X+transpose(X,7) ) ,4,6) ,4,6) +transpose((echo(transpose(transpose(X,-5) ,-7) ,4,6) +transpose(((X+transpose(X,7) ) +transpose(X,7) ) ,-7) ) ,4) ) +transpose(transpose(X,-5) ,7) ) ) ) |((transpose(transpose(transpose(X,-5) ,-7) ,4) |(transpose(transpose(((X+X) +X) ,-5) ,4) +transpose((transpose(X,-5) +(arpeggio(X) +transpose(((transpose(X,4) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(echo(X,4,6) ,7) ) ,4) ) ) ,12) ) ) |arpeggio((transpose((X|X) ,-7) |(transpose(X,-5) |X) ) ) ) ) ,-5) ,7) ) ,7) ) ) |shuffle((((transpose(arpeggio(echo((shuffle(arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) ) +transpose((step(X,12) +transpose(((X+transpose(X,4) ) +transpose(step(X,12) ,7) ) ,12) ) ,7) ) ,4,6) ) ,-5) +transpose(((((echo((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) ,4,6) |(((X|step(X,12) ) +transpose((((X+transpose(shuffle(X) ,4) ) +transpose(X,7) ) +transpose(((X+transpose(X,7) ) |echo(X,4,6) ) ,7) ) ,7) ) |(step(transpose(arpeggio(X) ,-7) ,12) +transpose((((X|X) +transpose((X+X) ,4) ) +transpose((X|X) ,7) ) ,4) ) ) ) +transpose(((((transpose(X,-7) +X) +transpose((X+transpose(X,12) ) ,4) ) +transpose(shuffle(X) ,7) ) +transpose(transpose(transpose((transpose(X,-5) +arpeggio(X) ) ,-5) ,-5) ,12) ) ,-5) ) +transpose((echo((((X+transpose((X+transpose(X,7) ) ,4) ) +transpose(transpose(X,-5) ,7) ) |shuffle((X|(X|X) ) ) ) ,4,6) |(arpeggio(arpeggio(((X|X) +transpose(transpose(X,-7) ,12) ) ) ) |((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) +transpose(transpose(step(X,12) ,-5) ,4) ) +transpose(((shuffle(X) +echo(X,4,6) ) |arpeggio(X) ) ,7) ) ) ) ,7) ) +transpose(shuffle(transpose((arpeggio(((transpose(X,-5) |echo(((X|X) +transpose(X,4) ) ,4,6) ) +(transpose((transpose(X,-5) +echo(transpose(X,4) ,4,6) ) ,-5) +((X|X) +transpose((X+transpose(X,7) ) ,4) ) ) ) ) +transpose((((X|transpose((X+transpose(X,7) ) ,-7) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +(transpose(X,-5) +X) ) ,7) ) |(shuffle(X) +transpose(arpeggio(transpose(X,4) ) ,7) ) ) ,-5) ) ,4) ) ,7) ) ,7) ) |echo(((shuffle(transpose(transpose(arpeggio(((transpose((X+transpose(X,12) ) ,-7) +(transpose(X,-5) +transpose((X+X) ,7) ) ) +transpose((arpeggio(((X+transpose(step(X,12) ,4) ) +transpose(transpose(X,-5) ,7) ) ) +transpose(((echo(X,4,6) +transpose((X+transpose((X|X) ,12) ) ,4) ) +transpose(transpose(X,-5) ,7) ) ,12) ) ,7) ) ) ,-5) ,4) ) +transpose(transpose(transpose(((arpeggio(echo(transpose(transpose(X,4) ,-5) ,4,6) ) +transpose(arpeggio(echo(arpeggio(shuffle(X) ) ,4,6) ) ,12) ) +(arpeggio(transpose(((X|X) +X) ,-7) ) +transpose(((((X+transpose(X,12) ) +transpose(X,-7) ) +transpose(step(X,12) ,-7) ) +transpose((transpose(transpose(X,-5) ,-7) +(((X|X) +transpose(transpose(X,-7) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ) ,7) ) ,7) ) ) ,4) ,-7) ,4) ) +(shuffle(((echo((((X+transpose(X,4) ) +transpose(X,7) ) |X) ,4,6) +transpose(((transpose(X,4) +transpose(transpose(X,-5) ,4) ) +transpose(transpose(transpose(X,-5) ,-7) ,7) ) ,4) ) +transpose(arpeggio(transpose(echo(echo(X,4,6) ,4,6) ,4) ) ,7) ) ) +transpose(arpeggio(((step(step(X,12) ,12) +transpose(arpeggio((transpose((step(X,12) +transpose(X,12) ) ,4) +transpose(echo(X,4,6) ,12) ) ) ,4) ) +transpose((transpose(((transpose((X|X) ,4) +(X+transpose(X,-7) ) ) +transpose(transpose(X,-5) ,12) ) ,4) +transpose(((X+transpose(X,4) ) +(shuffle(X) +transpose((transpose(X,-7) |(shuffle(X) +transpose(X,12) ) ) ,12) ) ) ,12) ) ,7) ) ) ,12) ) ) ,4,6) ) |step(((arpeggio((((X|(X+X) ) +transpose(shuffle(X) ,7) ) |transpose(arpeggio(transpose((X|(X+transpose(X,12) ) ) ,4) ) ,-7) ) ) +transpose(((X+transpose(((X|X) |((arpeggio(X) +transpose(X,4) ) +transpose(X,7) ) ) ,4) ) +transpose(step((X+transpose(X,-7) ) ,12) ,7) ) ,4) ) +transpose((((transpose(((transpose(X,-7) +transpose(transpose(X,4) ,4) ) +transpose((X+X) ,7) ) ,-5) |X) +transpose(transpose(transpose((shuffle(X) +transpose(X,-5) ) ,-7) ,4) ,12) ) +transpose(transpose(transpose(step(echo(transpose(X,-5) ,4,6) ,12) ,-5) ,-5) ,7) ) ,7) ) ,12) ) ) ) ,-5) ,12) )
random seed used was 95958010

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