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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After 19 generations the expression "X" became this:
((transpose(arpeggio((((arpeggio(((((transpose(X,4) |transpose(X,-5) ) +(transpose(X,-7) +(X|X) ) ) |(((((X+transpose(X,4) ) +transpose(X,7) ) |((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose((((X+X) +X) +(X|step(X,12) ) ) ,7) ) +transpose(((transpose(X,-5) +X) +transpose(((transpose(X,-7) +transpose(X,7) ) +transpose(arpeggio(shuffle(X) ) ,12) ) ,7) ) ,12) ) ) |transpose(echo((transpose(X,-7) |(X|X) ) ,4,6) ,-7) ) ) |shuffle(((transpose((X+transpose(shuffle(X) ,12) ) ,-7) +transpose((((X+transpose(X,12) ) +transpose(transpose(X,-7) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,12) ) +transpose(transpose(step(X,12) ,4) ,12) ) ) ) +transpose((transpose(((((((transpose(transpose((X+transpose(X,12) ) ,-7) ,-7) +transpose((transpose(shuffle(X) ,-7) |X) ,4) ) +transpose((transpose(X,-5) +(((X+X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(arpeggio(X) ,7) ) ) ,7) ) +transpose((shuffle(arpeggio((X+transpose(X,12) ) ) ) |((X+transpose(step(X,12) ,4) ) +transpose(X,7) ) ) ,7) ) +transpose(((step(X,12) |transpose(X,4) ) +(echo(X,4,6) +transpose(((X+transpose(X,7) ) +transpose(transpose(X,-5) ,12) ) ,7) ) ) ,-7) ) +echo(step((X+X) ,12) ,4,6) ) +transpose((step(shuffle(X) ,12) +transpose((step(shuffle(X) ,12) |arpeggio((echo(X,4,6) +transpose((X+X) ,12) ) ) ) ,7) ) ,12) ) ,-5) +transpose(step(((transpose((echo(X,4,6) +step((X+transpose((X|X) ,7) ) ,12) ) ,4) +transpose(echo(echo(X,4,6) ,4,6) ,4) ) +transpose(transpose(transpose(step(X,12) ,-7) ,4) ,7) ) ,12) ,7) ) ,4) ) +transpose(((echo(transpose((X+X) ,-5) ,4,6) +transpose((((X+transpose((X+transpose(X,7) ) ,4) ) +transpose(shuffle(X) ,7) ) |((X+transpose(X,12) ) +transpose(X,12) ) ) ,4) ) +transpose(echo(((transpose(transpose(X,-5) ,-7) +transpose((arpeggio(X) +transpose(transpose(X,4) ,12) ) ,-5) ) +transpose(echo(X,4,6) ,7) ) ,4,6) ,7) ) ,-7) ) ) ,-5) +transpose(((transpose(transpose(((((arpeggio(arpeggio(transpose(X,-5) ) ) +transpose(transpose(transpose((X+transpose(X,7) ) ,-5) ,-7) ,12) ) +transpose((arpeggio((step(X,12) +(echo(X,4,6) +transpose(transpose(X,4) ,7) ) ) ) +transpose((transpose(transpose(X,-7) ,4) +(transpose((X+transpose(X,12) ) ,-7) +transpose((X|X) ,4) ) ) ,7) ) ,4) ) +transpose(transpose(step(X,12) ,-5) ,7) ) |transpose(shuffle(step((X+transpose(X,12) ) ,12) ) ,-5) ) ,4) ,4) +transpose(transpose(echo((transpose(((((X+X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose((X|X) ,7) ) |shuffle(X) ) ,4) +(((transpose(((X+transpose((X|X) ,4) ) +transpose(X,7) ) ,-5) |(step((shuffle(step(X,12) ) +transpose((transpose(X,-5) +(X+transpose(X,12) ) ) ,7) ) ,12) +transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) ,7) ) ) |transpose(transpose(((arpeggio(X) +transpose(transpose((X+transpose(X,12) ) ,-7) ,4) ) +transpose(transpose(X,-7) ,7) ) ,-7) ,-7) ) +((((transpose(X,-7) +transpose((X+transpose(X,7) ) ,4) ) +transpose(transpose(X,4) ,7) ) +transpose(((transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ,4) +transpose((transpose(transpose(X,4) ,-7) +echo(X,4,6) ) ,4) ) +transpose(shuffle(shuffle(X) ) ,7) ) ,7) ) +((((transpose(transpose(X,-7) ,-5) +transpose(X,12) ) +transpose(shuffle((X+((X+transpose(X,4) ) +transpose(X,7) ) ) ) ,7) ) +transpose(((X+transpose(X,12) ) |X) ,12) ) |(((transpose(X,-5) |((X+transpose(X,4) ) +transpose(arpeggio(X) ,7) ) ) +transpose(((X|X) +transpose(X,7) ) ,4) ) +transpose(echo(((X+transpose(X,12) ) +step(X,12) ) ,4,6) ,7) ) ) ) ) ) ,4,6) ,-7) ,4) ) +transpose(((((arpeggio(echo(X,4,6) ) +transpose((transpose(step((transpose(X,4) +transpose((X+X) ,12) ) ,12) ,4) +transpose(arpeggio(arpeggio((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(X,12) ) ,7) ) ) ) ,12) ) ,12) ) +transpose(arpeggio(((transpose(transpose((X+transpose((X+transpose(X,12) ) ,12) ) ,4) ,4) +transpose((transpose(X,-5) +transpose(transpose((transpose(shuffle(X) ,-7) +transpose(echo(X,4,6) ,-7) ) ,4) ,12) ) ,4) ) +transpose((transpose(((transpose((arpeggio(X) +X) ,4) +transpose(transpose(transpose(transpose(X,4) ,-7) ,-7) ,4) ) +transpose(((X+transpose(X,7) ) +transpose(echo(X,4,6) ,12) ) ,7) ) ,4) |arpeggio(transpose(X,4) ) ) ,7) ) ) ,7) ) |echo((arpeggio(transpose(transpose(transpose((X+transpose(X,7) ) ,-5) ,4) ,-7) ) +step(transpose(arpeggio((X+transpose(X,12) ) ) ,-5) ,12) ) ,4,6) ) +transpose(((transpose(arpeggio(echo(transpose(transpose(transpose((X+transpose(X,12) ) ,-5) ,4) ,-7) ,4,6) ) ,-7) +transpose(echo(transpose(echo(step(step(((X+transpose(X,7) ) |transpose(transpose((X|X) ,4) ,-7) ) ,12) ,12) ,4,6) ,-7) ,4,6) ,-5) ) +transpose(step((shuffle((shuffle(((((transpose(X,4) +(X+X) ) +transpose((X|X) ,12) ) +transpose(echo((echo(X,4,6) +transpose(transpose(X,-7) ,-5) ) ,4,6) ,4) ) +transpose(transpose(transpose(X,-5) ,-5) ,7) ) ) +transpose(((transpose(transpose(X,-7) ,-5) +transpose(echo(transpose(X,4) ,4,6) ,7) ) +(((X+(X+X) ) +(shuffle(X) +transpose((X+X) ,12) ) ) |transpose(transpose((transpose(X,4) |transpose(X,4) ) ,4) ,-7) ) ) ,7) ) ) +(((step((echo(X,4,6) +transpose(((X|X) |arpeggio(X) ) ,12) ) ,12) +transpose((((transpose((transpose(X,4) +transpose(((transpose(X,-7) +transpose(X,4) ) +transpose(shuffle(X) ,7) ) ,7) ) ,-7) +transpose((step((X+transpose(X,7) ) ,12) |arpeggio(X) ) ,7) ) +transpose((((X+X) +transpose((X+transpose(X,7) ) ,-7) ) +((transpose(X,4) +transpose(transpose(X,-7) ,4) ) +transpose(X,7) ) ) ,4) ) +transpose((transpose(X,-5) +transpose(echo(step(arpeggio(X) ,12) ,4,6) ,12) ) ,7) ) ,4) ) +transpose(step(echo((((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,7) ) +transpose((X+transpose(X,12) ) ,7) ) |(transpose(X,-7) |X) ) ,4,6) ,12) ,7) ) +transpose(arpeggio(((((X+transpose(X,12) ) +transpose(arpeggio(X) ,7) ) |arpeggio((X+X) ) ) +((transpose(X,-7) +transpose((X|X) ,7) ) +((X+transpose(X,12) ) |X) ) ) ) ,-5) ) ) ,12) ,7) ) ,12) ) ,7) ) ,12) ) |((((transpose(transpose(transpose(((((X|X) +transpose((X+transpose(X,12) ) ,12) ) +((X+transpose(X,7) ) |shuffle(X) ) ) |transpose(X,-7) ) ,4) ,-7) ,-5) |(transpose(transpose((transpose(step((transpose((X+transpose((X|X) ,12) ) ,4) |(arpeggio((X+X) ) +transpose((X+transpose((X+X) ,7) ) ,12) ) ) ,12) ,-5) |transpose(arpeggio(((((X+X) +transpose(((X+X) +transpose(shuffle(X) ,12) ) ,7) ) |X) +transpose(((transpose(transpose(transpose(X,-5) ,-7) ,4) +transpose(transpose(X,-7) ,4) ) +transpose(((X+transpose((X+transpose(X,7) ) ,12) ) +transpose(step(transpose(X,-7) ,12) ,7) ) ,7) ) ,12) ) ) ,-7) ) ,-7) ,-7) |transpose(transpose(step((shuffle((transpose(X,-7) |X) ) +transpose(((transpose((X+transpose((X+X) ,7) ) ,-7) +transpose(step(X,12) ,4) ) +transpose(((X+transpose(X,7) ) +transpose(X,12) ) ,7) ) ,7) ) ,12) ,-7) ,-5) ) ) +step(transpose((arpeggio(((transpose(((transpose(X,-5) +transpose((X+transpose(transpose(X,-5) ,12) ) ,4) ) +transpose(transpose(transpose(X,4) ,-5) ,7) ) ,-5) +arpeggio(((((X|X) +transpose(transpose(X,4) ,12) ) +transpose(transpose(X,4) ,4) ) +transpose((arpeggio(X) +X) ,7) ) ) ) +(((X+(X+transpose(X,12) ) ) +transpose((shuffle(X) |X) ,4) ) +transpose((((X+X) +X) +(X|(X|X) ) ) ,7) ) ) ) |(((shuffle(transpose(X,4) ) +transpose(transpose(transpose(transpose(X,-5) ,-7) ,-5) ,12) ) +transpose(((transpose(X,-7) +transpose((step(X,12) +transpose(arpeggio(X) ,12) ) ,4) ) +transpose(transpose(X,4) ,7) ) ,-5) ) +step(echo(((((transpose(X,4) +(X+transpose(X,12) ) ) +echo((X+transpose(X,12) ) ,4,6) ) |shuffle(shuffle(X) ) ) |(step(transpose(step(X,12) ,-5) ,12) +arpeggio(shuffle(X) ) ) ) ,4,6) ,12) ) ) ,-5) ,12) ) +transpose((((transpose(arpeggio(transpose((transpose((shuffle(X) +step(transpose(X,4) ,12) ) ,4) +transpose((shuffle(transpose(X,4) ) +transpose(((((step(transpose(X,-5) ,12) +X) |((X+X) +X) ) +transpose(transpose((X|X) ,-7) ,12) ) +(transpose(X,-7) |((shuffle(echo((X+transpose(X,7) ) ,4,6) ) +transpose(transpose((transpose(X,-7) +X) ,-5) ,4) ) +transpose(shuffle((X+transpose(X,12) ) ) ,7) ) ) ) ,7) ) ,12) ) ,-5) ) ,-7) |(transpose((((shuffle(arpeggio(((((X+transpose(X,12) ) +transpose(X,-7) ) +transpose(transpose(X,-7) ,4) ) +transpose(step(X,12) ,7) ) ) ) +transpose(transpose((X+transpose((transpose(transpose(X,-5) ,4) +(X+transpose(X,7) ) ) ,12) ) ,-5) ,-7) ) +transpose(((arpeggio(transpose(X,-5) ) |((transpose(X,4) +transpose(X,4) ) +transpose(X,7) ) ) |(shuffle(transpose(arpeggio(X) ,-5) ) |((((transpose(X,4) +transpose(transpose(X,-5) ,7) ) |((X|X) +step(X,12) ) ) +((X+transpose((X+transpose(X,12) ) ,7) ) +shuffle((transpose(X,-5) +transpose(transpose(X,4) ,12) ) ) ) ) +transpose((X+transpose(X,12) ) ,12) ) ) ) ,4) ) +transpose(shuffle(transpose(transpose(transpose(X,-5) ,-7) ,4) ) ,7) ) ,4) |shuffle(echo(transpose(transpose(((X+X) +transpose(transpose(X,4) ,7) ) ,4) ,4) ,4,6) ) ) ) +transpose((((((transpose(((arpeggio(X) |X) +((transpose(transpose(transpose(step(X,12) ,-7) ,-5) ,4) +transpose(echo(step(X,12) ,4,6) ,4) ) +transpose(((step((X+(X+X) ) ,12) +transpose(((transpose(X,4) |X) +transpose(transpose(X,-5) ,12) ) ,4) ) +transpose(((((X+transpose(X,7) ) |X) +transpose(step(transpose(X,4) ,12) ,4) ) +transpose(X,7) ) ,7) ) ,7) ) ) ,-7) +transpose(echo(transpose(((((echo((X|X) ,4,6) +transpose(transpose(transpose(transpose(X,-5) ,-5) ,-5) ,7) ) +transpose((((X+transpose(X,-7) ) +transpose(transpose((X+transpose(X,12) ) ,4) ,12) ) +transpose(transpose(X,-5) ,7) ) ,4) ) +transpose((arpeggio(echo(X,4,6) ) +((transpose(X,4) +transpose(transpose(X,-7) ,4) ) +transpose(X,7) ) ) ,7) ) +arpeggio(((transpose((X+X) ,4) +transpose((transpose(X,-7) +transpose(X,-7) ) ,4) ) +transpose((((transpose(X,-5) +transpose(X,4) ) +transpose((X|X) ,7) ) +transpose(transpose(echo(X,4,6) ,4) ,12) ) ,7) ) ) ) ,-7) ,4,6) ,4) ) +transpose(shuffle(transpose(((arpeggio(transpose((step(((X|X) +transpose((X|X) ,7) ) ,12) +transpose(transpose(transpose(X,-7) ,-5) ,12) ) ,-7) ) |transpose((transpose(arpeggio(X) ,4) +transpose(((arpeggio(X) +transpose(echo(X,4,6) ,12) ) +transpose(shuffle(X) ,12) ) ,7) ) ,4) ) +(arpeggio((((X+transpose(X,4) ) +transpose(X,7) ) +(step((X+transpose(X,12) ) ,12) +transpose(((X+transpose(X,7) ) +transpose(step(X,12) ,7) ) ,7) ) ) ) +transpose(((step(X,12) +transpose((transpose(X,-5) +transpose(step(X,12) ,4) ) ,4) ) +transpose(((transpose(transpose(X,-7) ,-5) +transpose((X+arpeggio(X) ) ,4) ) +transpose(((X+transpose(X,7) ) +transpose(X,-7) ) ,7) ) ,7) ) ,4) ) ) ,-7) ) ,7) ) +transpose(transpose(((shuffle(transpose(((X+transpose(X,7) ) |(X|X) ) ,4) ) +transpose(((transpose(echo(transpose(X,-7) ,4,6) ,-7) |(transpose(X,4) +transpose((X+X) ,7) ) ) |(shuffle(transpose(X,-7) ) +transpose(step((((X+transpose(X,4) ) +transpose(X,7) ) +transpose((X+transpose(X,12) ) ,12) ) ,12) ,7) ) ) ,4) ) +transpose((((((X|echo((X+transpose(X,12) ) ,4,6) ) +(((X+transpose(echo(X,4,6) ,7) ) +transpose((transpose(X,-7) +transpose((X+transpose(X,12) ) ,12) ) ,4) ) +transpose((X|X) ,7) ) ) +transpose((shuffle(X) +transpose(((X+transpose(X,12) ) +transpose((X+transpose(X,7) ) ,7) ) ,4) ) ,4) ) +transpose(((shuffle(transpose(echo(X,4,6) ,-5) ) +transpose((X+transpose((transpose(X,-7) |transpose((X+transpose(X,7) ) ,-7) ) ,12) ) ,4) ) +transpose(((((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) +transpose(step(shuffle(X) ,12) ,4) ) +transpose((((X+X) +transpose(step(X,12) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,7) ) +transpose((((X+transpose(X,7) ) +transpose((X+X) ,12) ) +(arpeggio(X) |X) ) ,4) ) +transpose((transpose(transpose(X,-7) ,4) +(arpeggio(X) +X) ) ,7) ) ,7) ) ,7) ) |(transpose(X,-5) +transpose(((X+transpose(shuffle(X) ,7) ) +(X+step(X,12) ) ) ,12) ) ) ,7) ) ,-5) ,4) ) +transpose((((shuffle(step(step(transpose(transpose(((X+transpose(X,12) ) +(X|X) ) ,4) ,-5) ,12) ,12) ) +transpose((transpose(transpose((((transpose(echo(transpose(X,-5) ,4,6) ,-7) +transpose(((((X+transpose((shuffle(X) +transpose(transpose(X,-5) ,12) ) ,4) ) +transpose(X,7) ) +transpose(transpose(transpose(X,4) ,4) ,4) ) +transpose(arpeggio(shuffle(transpose(X,4) ) ) ,7) ) ,4) ) +transpose(shuffle(((transpose(X,-7) |((X+transpose(X,4) ) +transpose(X,7) ) ) |(X+X) ) ) ,7) ) +transpose(echo(transpose(transpose((X|X) ,-7) ,-5) ,4,6) ,7) ) ,-5) ,-7) +(transpose(arpeggio(transpose(arpeggio((transpose((X+X) ,-5) +transpose(transpose(X,-7) ,12) ) ) ,-5) ) ,4) +((transpose(arpeggio(echo(X,4,6) ) ,-7) +transpose((transpose(arpeggio(echo(echo(X,4,6) ,4,6) ) ,-7) |transpose((transpose(echo(arpeggio(X) ,4,6) ,-5) +transpose((transpose(X,-5) +transpose((X|X) ,12) ) ,12) ) ,-7) ) ,4) ) +transpose((transpose(X,4) |shuffle((X+X) ) ) ,7) ) ) ) ,7) ) +transpose(step((shuffle(transpose((transpose(X,4) |(X+transpose(X,12) ) ) ,-5) ) +transpose((((arpeggio((X+transpose(X,12) ) ) +transpose(((X+transpose(X,-7) ) +transpose((X+transpose(X,7) ) ,7) ) ,7) ) |echo(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ,4,6) ) +transpose(echo(((X+(transpose(X,-5) +X) ) |step((echo(X,4,6) +X) ,12) ) ,4,6) ,7) ) ,7) ) ,12) ,4) ) +transpose(transpose(transpose((step(X,12) |(X+transpose(X,7) ) ) ,-5) ,-7) ,7) ) ,7) ) +transpose(((transpose((transpose(step(transpose(X,-5) ,12) ,4) +transpose((transpose((transpose(((X+transpose(X,7) ) |step(X,12) ) ,-7) |(((arpeggio(X) +transpose(echo(X,4,6) ,7) ) +transpose(step((X|X) ,12) ,4) ) +transpose(transpose(X,-5) ,7) ) ) ,4) +transpose(transpose((X+X) ,-7) ,-5) ) ,12) ) ,-7) |(arpeggio(transpose((X|X) ,4) ) +transpose(arpeggio(transpose((((X+transpose(X,12) ) +transpose((X+X) ,12) ) +echo(X,4,6) ) ,-7) ) ,7) ) ) |transpose((((((((transpose(X,4) +transpose((X|X) ,12) ) +(X+transpose((X|X) ,7) ) ) |transpose(X,4) ) +transpose((X+transpose(X,12) ) ,4) ) +transpose(transpose((transpose(X,4) |(X|X) ) ,-5) ,4) ) +transpose(echo(transpose((((X+transpose(X,7) ) +transpose(transpose(transpose(X,-5) ,4) ,4) ) +transpose(X,7) ) ,4) ,4,6) ,7) ) +((((((X|X) +(X+X) ) +transpose(((X+transpose(X,12) ) |(X|X) ) ,4) ) +transpose(arpeggio((X+X) ) ,7) ) +(echo(((X+transpose(X,7) ) +X) ,4,6) +transpose(transpose(transpose(X,4) ,-5) ,12) ) ) |(((step(X,12) +transpose(transpose(X,-7) ,12) ) +((X+transpose(X,4) ) +transpose(X,7) ) ) +echo(step(step((X+X) ,12) ,12) ,4,6) ) ) ) ,-7) ) ,7) ) ,12) ) +transpose((transpose(((transpose(echo(transpose((((transpose(step(X,12) ,-7) |((transpose(echo(X,4,6) ,4) +transpose(transpose(X,-7) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) |transpose(transpose(X,4) ,-7) ) ,7) ) ) +transpose(step((((transpose(X,-7) +X) +transpose(step(((transpose(X,-5) +transpose(X,4) ) +transpose(X,7) ) ,12) ,4) ) +transpose(shuffle(transpose(X,-5) ) ,7) ) ,12) ,4) ) +transpose(((transpose(echo(transpose(X,-7) ,4,6) ,-5) +transpose((shuffle(echo((X+transpose(X,12) ) ,4,6) ) +transpose(arpeggio(X) ,7) ) ,12) ) +shuffle((X+transpose(X,7) ) ) ) ,7) ) ,4) ,4,6) ,4) +transpose((echo(((shuffle(step(transpose(X,-5) ,12) ) +transpose(((((X+X) +transpose(transpose(X,4) ,7) ) |step((X+transpose(X,12) ) ,12) ) +echo(transpose(echo(X,4,6) ,-5) ,4,6) ) ,4) ) +transpose(transpose((((echo(X,4,6) |((X+X) +X) ) +transpose(((transpose(X,-5) +transpose(echo(X,4,6) ,4) ) +transpose(arpeggio(X) ,7) ) ,7) ) +transpose((transpose(X,4) +transpose(step((X|X) ,12) ,12) ) ,7) ) ,-7) ,7) ) ,4,6) +transpose((transpose(arpeggio(((transpose(X,-7) +transpose((X+(X+transpose(X,7) ) ) ,12) ) +transpose(((X+transpose(transpose(transpose(X,-5) ,-7) ,4) ) +transpose(step(X,12) ,7) ) ,12) ) ) ,4) |((shuffle(X) +step((((step(X,12) +transpose((X+transpose(X,12) ) ,4) ) +transpose(X,7) ) +transpose(((X|X) +X) ,7) ) ,12) ) |transpose((transpose(transpose(echo(transpose(X,4) ,4,6) ,4) ,4) +transpose(((echo(arpeggio(X) ,4,6) +transpose((transpose(X,-5) |X) ,7) ) +transpose(transpose(((X+X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,-5) ,12) ) ,7) ) ,4) ) ) ,12) ) ,4) ) +transpose(((transpose(transpose(((transpose(X,-7) |((X+transpose(transpose((X+X) ,4) ,12) ) +transpose((transpose(X,-5) +transpose(X,12) ) ,12) ) ) +transpose((transpose(transpose(X,4) ,-7) |(transpose(X,4) +X) ) ,7) ) ,4) ,-7) +transpose(transpose(transpose(transpose(arpeggio(transpose(echo(X,4,6) ,-7) ) ,4) ,-5) ,4) ,4) ) +transpose((echo((((step(transpose(X,-5) ,12) +transpose((arpeggio(X) +(X|X) ) ,12) ) |transpose(transpose((X|step(X,12) ) ,-5) ,-5) ) |(X|(X|X) ) ) ,4,6) |(echo((X|X) ,4,6) +(step(transpose(X,4) ,12) +(transpose(transpose((X+transpose(X,12) ) ,4) ,-5) |transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +X) +transpose((X+X) ,7) ) ,4) ) ) ) ) ,7) ) ,7) ) ,4) |((((step((arpeggio(((transpose(X,-5) +transpose(transpose((X+X) ,-5) ,4) ) +transpose(transpose((X+transpose(X,7) ) ,4) ,7) ) ) +arpeggio((step(X,12) +transpose(X,12) ) ) ) ,12) +transpose(transpose((((((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(arpeggio(X) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) +transpose(transpose(echo(X,4,6) ,-5) ,12) ) +transpose(transpose((transpose(X,-5) +(X+X) ) ,4) ,4) ) +transpose(transpose(transpose(transpose(X,-7) ,-5) ,-7) ,7) ) ,4) ,12) ) +transpose(step((((echo(((shuffle(X) +transpose(arpeggio(X) ,7) ) +transpose(echo(step(X,12) ,4,6) ,7) ) ,4,6) +transpose(transpose(transpose(X,-5) ,-7) ,4) ) +transpose(transpose(((X+X) +transpose((X+transpose(X,4) ) ,7) ) ,4) ,4) ) +transpose(transpose(((transpose(X,-5) +transpose(X,-7) ) +shuffle(X) ) ,4) ,7) ) ,12) ,4) ) +transpose(((X|((X|X) |X) ) +transpose(transpose(X,-5) ,-5) ) ,7) ) |arpeggio(transpose((transpose(X,-5) +(X+transpose((X+X) ,7) ) ) ,4) ) ) ) ,12) ) ,4) ) +transpose(echo((transpose(echo((transpose(transpose((((X|X) +(transpose(X,-5) +transpose(transpose(X,-5) ,12) ) ) +transpose(transpose(arpeggio((X|X) ) ,-7) ,7) ) ,4) ,4) |(((transpose((X+transpose(X,7) ) ,-5) +transpose(((X+transpose(X,7) ) +(X|X) ) ,4) ) +transpose(transpose((X+X) ,4) ,7) ) |(shuffle(transpose(echo(X,4,6) ,4) ) +transpose((transpose(X,4) +transpose(X,4) ) ,-7) ) ) ) ,4,6) ,-7) +shuffle((step(transpose(transpose(transpose(arpeggio(transpose(X,-5) ) ,-7) ,-5) ,-7) ,12) +transpose(transpose((transpose(step(transpose(transpose((X+X) ,-5) ,4) ,12) ,-7) |transpose(arpeggio((transpose(X,-5) +transpose(transpose(X,-5) ,12) ) ) ,-5) ) ,4) ,12) ) ) ) ,4,6) ,7) ) )
random seed used was 140113444

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