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:
Seed:
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Phrase for X:
# of Tracks:
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After 20 generations the expression "X" became this:
step((shuffle(transpose(transpose(((shuffle(((transpose(shuffle((step(X,12) +transpose(echo(X,4,6) ,12) ) ) ,-7) |(echo((echo(X,4,6) +transpose((X+transpose(X,12) ) ,7) ) ,4,6) +transpose(((echo(step(transpose(X,-5) ,12) ,4,6) +transpose(((transpose(X,4) +transpose(X,12) ) +transpose(transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ,-5) ,12) ) ,4) ) +transpose(transpose((X+X) ,4) ,7) ) ,7) ) ) |transpose(transpose(((transpose(arpeggio(X) ,4) |(X+transpose((arpeggio(X) +transpose(step(X,12) ,12) ) ,4) ) ) |transpose((transpose(shuffle(transpose(transpose(X,-5) ,-5) ) ,4) +(transpose(((X+X) |X) ,4) +(transpose((((X|X) +transpose(X,4) ) +transpose((X+transpose(X,7) ) ,7) ) ,-5) +transpose(arpeggio(X) ,-7) ) ) ) ,-5) ) ,-5) ,-5) ) ) +transpose(((echo((((((((transpose(X,-5) |(X|X) ) +transpose(shuffle(X) ,4) ) |transpose(transpose(arpeggio(X) ,-7) ,-5) ) |step((X+transpose((X+transpose(X,7) ) ,12) ) ,12) ) |shuffle(transpose((echo(step(X,12) ,4,6) |(X+(X+transpose(X,12) ) ) ) ,-7) ) ) +(transpose(X,4) +transpose((X+transpose((X+X) ,12) ) ,12) ) ) |(((((X+X) +transpose((shuffle((X+X) ) |X) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +X) ,7) ) +shuffle((X+transpose(X,7) ) ) ) +(((((X+transpose(X,7) ) +transpose(X,-7) ) +((X+transpose(X,12) ) +transpose((X+transpose(X,12) ) ,7) ) ) +transpose(transpose(arpeggio(transpose(X,4) ) ,4) ,7) ) +transpose(((shuffle(X) +X) +transpose((transpose((X+transpose(X,12) ) ,4) |X) ,7) ) ,12) ) ) ) ,4,6) +(((((transpose(((transpose(X,-7) +transpose(X,7) ) +transpose((X+transpose(X,7) ) ,7) ) ,-7) |((((X+X) +transpose((arpeggio(X) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(X,7) ) ,12) ) ,12) ) ,4) ) +transpose((((X+transpose((X|X) ,4) ) +transpose((X|X) ,7) ) +arpeggio(step(X,12) ) ) ,7) ) +(echo(transpose(X,4) ,4,6) |((transpose((X+transpose(X,7) ) ,-7) +transpose((X+X) ,4) ) +transpose(echo((X|X) ,4,6) ,7) ) ) ) ) +echo((((shuffle(transpose(X,-5) ) +transpose((X+transpose(X,4) ) ,4) ) +transpose((X+(X+transpose(X,7) ) ) ,7) ) +step((transpose(echo(X,4,6) ,-5) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ) ,12) ) ,4,6) ) |transpose(shuffle((step(X,12) +transpose(transpose((X|X) ,-7) ,12) ) ) ,-5) ) +transpose(((transpose(transpose((X+transpose(X,7) ) ,-5) ,4) +transpose(((transpose(X,4) |X) +transpose(step((transpose(X,4) +transpose(X,7) ) ,12) ,7) ) ,12) ) +transpose(((((X+X) +transpose(transpose(X,-5) ,12) ) +transpose(transpose(transpose((X+transpose(X,7) ) ,-5) ,-5) ,4) ) +transpose(echo(((arpeggio(X) +transpose(arpeggio(X) ,12) ) +transpose((X|X) ,-7) ) ,4,6) ,7) ) ,12) ) ,12) ) +transpose(((transpose(((transpose((X|X) ,4) +transpose((echo(transpose(X,4) ,4,6) |step((X+transpose(X,7) ) ,12) ) ,12) ) +transpose(((X|(transpose(X,-5) +(X+transpose(X,7) ) ) ) +transpose(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ,12) ) ,7) ) ,-5) +transpose((step(echo((X+transpose(transpose(transpose(X,-7) ,-5) ,7) ) ,4,6) ,12) +transpose(echo(X,4,6) ,7) ) ,4) ) +transpose(shuffle((echo(X,4,6) +transpose((((X+transpose(X,7) ) +transpose(echo(step(X,12) ,4,6) ,4) ) +transpose(X,7) ) ,12) ) ) ,7) ) ,12) ) ) +transpose(shuffle((arpeggio(transpose((transpose(transpose(transpose(transpose(X,4) ,-7) ,4) ,4) +transpose((transpose(X,-5) |step(transpose((X+transpose(X,12) ) ,4) ,12) ) ,7) ) ,-7) ) +transpose(step(transpose(transpose((X+transpose(X,7) ) ,-5) ,4) ,12) ,7) ) ) ,12) ) ,12) ) +transpose((echo(transpose((shuffle(transpose(transpose(echo(X,4,6) ,-7) ,-5) ) +transpose((arpeggio(echo(transpose(X,-5) ,4,6) ) |((transpose(X,4) +transpose((shuffle(X) |transpose(X,-7) ) ,7) ) +transpose(echo(step(echo(X,4,6) ,12) ,4,6) ,7) ) ) ,-7) ) ,4) ,4,6) +transpose(transpose(transpose(echo(transpose(transpose(echo(((transpose(X,4) +transpose(step(transpose(X,-7) ,12) ,4) ) +transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,7) ) ,4,6) ,4) ,4) ,4,6) ,-5) ,4) ,7) ) ,12) ) ,-7) ,4) ) +transpose(((((((transpose(transpose((transpose(arpeggio(transpose((echo(shuffle(X) ,4,6) +(transpose(X,-7) |arpeggio((X+X) ) ) ) ,4) ) ,4) +transpose(echo(((X+transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,4,6) ,7) ) ,4) ,-7) |transpose(transpose((transpose((X+transpose(((step((echo(X,4,6) +transpose(X,12) ) ,12) +transpose(echo((X+X) ,4,6) ,-7) ) +transpose((arpeggio(transpose(X,-7) ) |((transpose(X,4) +transpose(X,-7) ) +X) ) ,7) ) ,12) ) ,-7) +arpeggio(echo((X+transpose(step(X,12) ,12) ) ,4,6) ) ) ,-5) ,-5) ) +transpose((((((((((X+transpose(X,7) ) |X) |((X+transpose(X,7) ) +transpose(X,-7) ) ) +transpose((transpose(X,-7) |((echo(X,4,6) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ) ,7) ) +transpose(echo(arpeggio((transpose(X,4) |((X+transpose(X,7) ) +(X+X) ) ) ) ,4,6) ,12) ) |(transpose(arpeggio(transpose(X,4) ) ,-7) +transpose(transpose(((transpose(X,-7) +step(X,12) ) +step((echo(transpose(X,4) ,4,6) +(((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,7) ) ) ,12) ) ,-5) ,12) ) ) |(echo(transpose(((X+transpose(X,7) ) +shuffle(transpose(X,-5) ) ) ,-5) ,4,6) |transpose(transpose(transpose(transpose(transpose(X,4) ,4) ,-5) ,4) ,-7) ) ) +((transpose(((shuffle(X) +((X+transpose(X,7) ) +transpose(X,4) ) ) +(((transpose(arpeggio(X) ,-5) |X) |(transpose(X,-7) +transpose((X|X) ,12) ) ) +transpose(transpose(arpeggio(transpose(shuffle(X) ,-7) ) ,-5) ,-7) ) ) ,-7) |arpeggio(transpose((arpeggio((((transpose((X+X) ,-7) +transpose(((X+transpose(X,4) ) +transpose(echo(X,4,6) ,7) ) ,12) ) +transpose(transpose(X,-7) ,4) ) +transpose((arpeggio(arpeggio(X) ) +transpose(transpose(X,4) ,12) ) ,7) ) ) |(arpeggio(((X|(X+transpose(X,12) ) ) +transpose(transpose(X,-5) ,12) ) ) +transpose(transpose((echo(X,4,6) |X) ,-7) ,12) ) ) ,4) ) ) |shuffle(arpeggio(((((X|X) +transpose((X+transpose(X,12) ) ,7) ) +transpose(X,4) ) +((((X+transpose(X,-5) ) +transpose((arpeggio(X) +transpose(transpose(transpose(X,4) ,4) ,12) ) ,4) ) +transpose((X|step(X,12) ) ,7) ) +(transpose(transpose(step(X,12) ,-7) ,-5) |step((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,12) ) ) ) ) ) ) ) |transpose(transpose((((transpose(echo(transpose(transpose((X+transpose(X,12) ) ,-5) ,4) ,4,6) ,-5) |(transpose(X,-7) +transpose(transpose((X+X) ,-7) ,-7) ) ) |(X|echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ) ) |transpose((((X+transpose(((X+transpose(X,4) ) +transpose((X|X) ,7) ) ,12) ) |((X+step(X,12) ) +transpose(transpose(transpose(X,4) ,-5) ,4) ) ) +echo(((transpose(X,-5) +transpose(step(echo(transpose(X,4) ,4,6) ,12) ,4) ) +transpose((transpose((X+transpose(X,7) ) ,4) |(X+(X|X) ) ) ,7) ) ,4,6) ) ,4) ) ,-5) ,4) ) ,4) ) +transpose(transpose(transpose(((shuffle(((transpose(((arpeggio(arpeggio(X) ) +transpose(transpose(transpose(X,4) ,4) ,4) ) +transpose(X,7) ) ,-7) +((step((((arpeggio(X) +shuffle(transpose(X,-5) ) ) +arpeggio(X) ) +(((echo(X,4,6) +transpose(((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(transpose(X,4) ,7) ) ,4) ) +transpose((transpose(X,-5) +transpose(arpeggio(X) ,7) ) ,7) ) +transpose(X,-5) ) ) ,12) +step((transpose(X,-7) +transpose(X,-5) ) ,12) ) |((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose(X,-7) ,12) ) |(shuffle(X) +transpose(X,-7) ) ) ) ) +transpose(transpose((((shuffle((X|X) ) +transpose(((echo((X+transpose((X|X) ,12) ) ,4,6) +transpose(X,4) ) +transpose(transpose(arpeggio(transpose(X,-5) ) ,4) ,7) ) ,7) ) +transpose(((transpose(shuffle(X) ,4) +transpose(transpose(transpose(step(X,12) ,4) ,-5) ,4) ) +transpose((X|shuffle(transpose((X|X) ,-7) ) ) ,7) ) ,4) ) +transpose((transpose(X,4) +transpose(X,7) ) ,7) ) ,-7) ,12) ) ) +transpose((((transpose(echo((X+X) ,4,6) ,-7) +transpose(((X+transpose(transpose((X+X) ,-5) ,12) ) +transpose((transpose(X,-5) |transpose(transpose(X,4) ,-7) ) ,7) ) ,12) ) +transpose((transpose(X,4) |(((X+transpose(X,4) ) +transpose(X,7) ) +shuffle(X) ) ) ,-5) ) +transpose(transpose((((step(transpose((X+transpose(X,12) ) ,4) ,12) |step(X,12) ) |transpose(step(echo((transpose(X,4) +(X+transpose(X,7) ) ) ,4,6) ,12) ,-5) ) +transpose(echo((step(X,12) +transpose((X+transpose(X,7) ) ,7) ) ,4,6) ,-5) ) ,4) ,7) ) ,4) ) +transpose((((((transpose(X,-5) +shuffle(X) ) |(transpose(X,-5) +transpose(transpose(transpose(transpose((X|X) ,-7) ,-7) ,-5) ,7) ) ) +transpose(transpose((transpose(shuffle((X|X) ) ,4) +transpose(transpose(transpose(((transpose(X,-7) +transpose(transpose(X,-7) ,4) ) +transpose(X,7) ) ,4) ,4) ,7) ) ,-7) ,12) ) +transpose(transpose(((transpose(X,-7) +shuffle(X) ) +transpose((X+transpose(X,-5) ) ,-5) ) ,-7) ,4) ) +transpose(step(transpose(transpose((transpose((X|X) ,-7) +transpose((X+transpose(X,7) ) ,7) ) ,-7) ,4) ,12) ,7) ) ,7) ) ,-5) ,4) ,7) ) |echo(transpose(transpose((((shuffle((transpose(transpose((X+transpose(X,7) ) ,-7) ,-7) +transpose(step((shuffle(transpose(X,-5) ) |shuffle((transpose(X,-5) |X) ) ) ,12) ,7) ) ) +transpose(shuffle(transpose((((echo(transpose(X,-7) ,4,6) +transpose(transpose(shuffle(step(X,12) ) ,4) ,12) ) +transpose(transpose((transpose((X|X) ,4) +arpeggio((transpose(X,4) +transpose(X,7) ) ) ) ,4) ,4) ) +transpose(transpose(transpose(X,4) ,4) ,7) ) ,4) ) ,7) ) +transpose((((shuffle((echo((echo((X+transpose(X,12) ) ,4,6) +((X+transpose(X,12) ) +transpose(transpose(X,-7) ,12) ) ) ,4,6) +step(arpeggio(transpose(shuffle(X) ,-5) ) ,12) ) ) +transpose((transpose(transpose((echo(X,4,6) +transpose((transpose((X+transpose(X,7) ) ,-5) |(((X|X) +transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) ) ,12) ) ,-7) ,-7) +transpose((((((X|X) |X) +transpose(step(transpose(X,4) ,12) ,12) ) +transpose(shuffle(X) ,-7) ) +transpose(shuffle((transpose(X,-7) |(X|X) ) ) ,12) ) ,12) ) ,7) ) +transpose(transpose((((shuffle((((X+transpose(X,12) ) +transpose(X,4) ) +transpose(transpose(X,-5) ,7) ) ) +transpose(((X|X) |echo(X,4,6) ) ,4) ) +transpose(shuffle(transpose(transpose(X,4) ,-5) ) ,7) ) +transpose(transpose((transpose(X,-7) +(X|X) ) ,4) ,7) ) ,4) ,4) ) +transpose(echo((transpose(transpose(transpose(X,4) ,4) ,4) |arpeggio((X|X) ) ) ,4,6) ,7) ) ,12) ) +(((transpose(transpose(arpeggio(shuffle(X) ) ,-5) ,4) +transpose((transpose(transpose((echo(transpose(X,4) ,4,6) +transpose((X+transpose(X,7) ) ,4) ) ,-5) ,4) +(transpose(transpose(((X|transpose(X,4) ) +transpose(((X+transpose((X+X) ,12) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +X) ,4) ) ,12) ) ,-7) ,-5) +transpose(((((transpose(X,-5) |X) +transpose(shuffle(X) ,4) ) +transpose((X|X) ,7) ) |(X+transpose((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,7) ) ) ,7) ) ) ,7) ) +transpose(arpeggio((shuffle((transpose(transpose(X,-7) ,-7) +transpose(((shuffle(X) +transpose(transpose(X,-7) ,12) ) |((X+(X+transpose(X,7) ) ) |X) ) ,7) ) ) |((step((((shuffle(X) |X) +transpose((step(X,12) +(((X+transpose(X,4) ) +transpose(X,7) ) +(X|X) ) ) ,4) ) +transpose((shuffle(arpeggio(X) ) +transpose((echo(X,4,6) +transpose(X,7) ) ,12) ) ,7) ) ,12) +transpose((transpose(echo(((transpose(X,-7) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,4,6) ,-7) |echo(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,7) ) +transpose((X|(X+transpose(X,7) ) ) ,7) ) ,4,6) ) ,4) ) +transpose((transpose(((X+transpose(X,7) ) +transpose(transpose(X,-5) ,7) ) ,-7) +transpose(arpeggio(transpose((X+X) ,-7) ) ,12) ) ,7) ) ) ) ,4) ) +transpose((step(((shuffle(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) +transpose(transpose(((X+transpose((shuffle((X+X) ) +transpose((X|((X+transpose(X,4) ) +transpose(X,7) ) ) ,12) ) ,4) ) +transpose(arpeggio(transpose((X+transpose(X,7) ) ,4) ) ,7) ) ,-7) ,4) ) +transpose(arpeggio(shuffle(((transpose(transpose(X,-5) ,4) +transpose((X|X) ,7) ) +transpose((arpeggio(X) +transpose(X,12) ) ,12) ) ) ) ,7) ) ,12) +shuffle((step(transpose((((X+transpose(X,7) ) +transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) ,4) ,12) |echo((((step(X,12) +transpose(transpose(X,-7) ,4) ) +transpose((X+X) ,7) ) +transpose(X,7) ) ,4,6) ) ) ) ,7) ) ) ,-5) ,4) ,4,6) ) |(((shuffle(step(arpeggio(transpose(transpose(transpose(arpeggio(transpose(transpose(arpeggio(shuffle((transpose(X,4) +X) ) ) ,-5) ,-5) ) ,4) ,-7) ,-5) ) ,12) ) +transpose(step((echo(((arpeggio(transpose(((transpose((X+transpose(X,7) ) ,4) |X) |transpose(shuffle(X) ,-7) ) ,-5) ) +transpose((((X|X) +echo(transpose(X,4) ,4,6) ) +transpose((echo(X,4,6) |shuffle(X) ) ,12) ) ,7) ) +transpose((((transpose((transpose(X,-7) +(X+X) ) ,4) |transpose(X,-7) ) +transpose(transpose(((transpose(X,-7) +transpose(X,12) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ) ,-5) ,4) ) |echo(arpeggio(X) ,4,6) ) ,7) ) ,4,6) +(transpose((transpose(((X+transpose(X,12) ) +transpose(X,-7) ) ,-7) +transpose(((transpose(arpeggio(X) ,4) +transpose(transpose(transpose((X+transpose(X,7) ) ,-7) ,-7) ,4) ) +transpose(transpose(echo(X,4,6) ,4) ,7) ) ,7) ) ,-5) |arpeggio(step((echo(X,4,6) +X) ,12) ) ) ) ,12) ,12) ) +transpose(((transpose(shuffle(transpose(((((transpose(transpose(X,-5) ,-5) |transpose((shuffle(X) +X) ,-7) ) +transpose((((step(X,12) +transpose(X,12) ) +arpeggio(X) ) +((transpose(step(X,12) ,4) +transpose(shuffle(X) ,4) ) +transpose((arpeggio(X) |X) ,7) ) ) ,12) ) +transpose((shuffle(transpose(transpose(X,-7) ,-7) ) +transpose((arpeggio(X) |X) ,12) ) ,4) ) +transpose((echo(shuffle((X|X) ) ,4,6) +transpose(shuffle(transpose(((X|X) +transpose(((X+X) +transpose(X,7) ) ,7) ) ,-5) ) ,12) ) ,7) ) ,-7) ) ,-7) +transpose(transpose(echo(transpose((transpose((((shuffle(X) |X) |arpeggio((X+transpose(X,7) ) ) ) +transpose(echo((X+transpose(X,12) ) ,4,6) ,7) ) ,-5) +transpose(echo((transpose(X,-5) +((X+transpose(X,7) ) +X) ) ,4,6) ,12) ) ,-7) ,4,6) ,-5) ,4) ) +transpose(transpose(((transpose(((transpose(((arpeggio(X) |(X+X) ) +transpose((X+transpose(X,7) ) ,7) ) ,4) |echo(transpose(step(X,12) ,-5) ,4,6) ) +((transpose(transpose(shuffle(X) ,4) ,4) +transpose((arpeggio(X) |(X+transpose(X,12) ) ) ,7) ) +transpose(arpeggio(transpose(((X+X) |((X+X) +transpose(X,4) ) ) ,-5) ) ,7) ) ) ,-7) |(step((transpose((X+transpose(X,7) ) ,4) |(step(arpeggio(X) ,12) |(X+(X+transpose(X,12) ) ) ) ) ,12) +transpose(arpeggio(((shuffle(transpose((X|X) ,4) ) +transpose((((echo(X,4,6) +transpose((X+X) ,7) ) +transpose((X+transpose(X,12) ) ,7) ) +(((((X+transpose(X,4) ) +transpose(transpose(X,-7) ,7) ) +transpose(X,4) ) +transpose((X|transpose(X,4) ) ,7) ) +(X+X) ) ) ,4) ) +transpose(echo(((transpose(step(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ,-5) +transpose(step(arpeggio(transpose(X,-5) ) ,12) ,4) ) +transpose(echo(X,4,6) ,7) ) ,4,6) ,7) ) ) ,7) ) ) |shuffle(shuffle(((transpose(transpose((X+X) ,-7) ,-5) +transpose(transpose(((transpose(transpose(X,4) ,4) +transpose(X,4) ) +transpose(step((step(X,12) +X) ,12) ,7) ) ,-5) ,4) ) +transpose((shuffle(transpose(X,-5) ) +transpose(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ,7) ) ,7) ) ) ) ) ,-7) ,7) ) ,4) ) +transpose(arpeggio(step(transpose(((echo(shuffle(transpose((transpose((X|X) ,-7) +transpose(transpose(transpose((X|X) ,-5) ,-5) ,7) ) ,-7) ) ,4,6) +transpose((transpose((((X+transpose(X,12) ) |step((X+transpose(X,12) ) ,12) ) +transpose((transpose(X,-7) +transpose((shuffle(X) +X) ,12) ) ,12) ) ,-7) +(shuffle(transpose(X,-7) ) +transpose(arpeggio(transpose(((((X+transpose(X,7) ) +transpose(X,4) ) +transpose(X,7) ) +transpose(X,12) ) ,-7) ) ,12) ) ) ,4) ) +echo(step(step((transpose(arpeggio((shuffle(X) +echo(X,4,6) ) ) ,4) +transpose(arpeggio(arpeggio(echo(X,4,6) ) ) ,7) ) ,12) ,12) ,4,6) ) ,4) ,12) ) ,7) ) ) |(transpose(echo(((shuffle(transpose(transpose((shuffle(transpose((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) +(transpose(step(X,12) ,4) +transpose(echo(X,4,6) ,-5) ) ) ,4) ) +((step(transpose(((step(X,12) +step(X,12) ) +transpose((X+X) ,7) ) ,4) ,12) +transpose((step(((X+transpose((X+transpose(X,7) ) ,4) ) +transpose(X,7) ) ,12) |transpose((step(X,12) |(((X+transpose(X,4) ) +transpose(X,7) ) +(X+transpose(X,7) ) ) ) ,-5) ) ,4) ) +transpose((transpose((transpose(((X+transpose(X,7) ) +(X+transpose(X,12) ) ) ,-7) +transpose(transpose(X,-5) ,12) ) ,4) +(echo((step(X,12) +transpose(transpose(X,-5) ,7) ) ,4,6) +transpose((echo(X,4,6) +transpose(((transpose(X,-7) +transpose((X+X) ,4) ) +transpose(X,7) ) ,7) ) ,7) ) ) ,7) ) ) ,4) ,-5) ) +transpose(step((transpose(transpose((echo(transpose((X+transpose(X,4) ) ,4) ,4,6) +transpose(echo((X+transpose(X,7) ) ,4,6) ,-7) ) ,-5) ,-5) +step((arpeggio((arpeggio(X) +transpose(X,12) ) ) +transpose(transpose((((X+transpose(X,7) ) |X) +(X+transpose(X,12) ) ) ,4) ,12) ) ,12) ) ,12) ,4) ) +transpose(transpose((transpose(transpose(transpose((X+X) ,-5) ,-7) ,-5) +(transpose(echo(shuffle((transpose(((transpose(X,-5) +transpose((X+transpose(X,12) ) ,4) ) +transpose(X,7) ) ,-7) +transpose(transpose(X,-7) ,12) ) ) ,4,6) ,-7) +transpose(shuffle(((shuffle(X) +(X+transpose(X,12) ) ) +(arpeggio((X|X) ) +transpose(((shuffle(X) +step(X,12) ) +(((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(X,7) ) ,7) ) ) ,12) ) ) ) ,7) ) ) ,-5) ,7) ) ,4,6) ,-7) +transpose(arpeggio(((((echo(echo((X+transpose(X,7) ) ,4,6) ,4,6) +transpose(transpose((transpose(X,-5) +((X+transpose(X,12) ) |transpose(X,-5) ) ) ,-7) ,4) ) +transpose(shuffle(echo(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ,4,6) ) ,7) ) |(transpose(((transpose(X,-7) +((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose((echo(X,4,6) |step(X,12) ) ,7) ) ,4) +(X+(((X+transpose(X,4) ) +transpose(X,7) ) |(transpose(X,4) +transpose(X,12) ) ) ) ) ) +transpose(step(step((transpose(shuffle(shuffle(X) ) ,4) |transpose(arpeggio(step(arpeggio(X) ,12) ) ,-5) ) ,12) ,12) ,7) ) ) ,7) ) ) ,7) ) ,12)
random seed used was 3691115

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