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(echo((echo(((((step(step((shuffle(X) |echo(X,4,6) ) ,12) ,12) +(shuffle(((X+transpose(X,12) ) +X) ) +arpeggio(X) ) ) +transpose(step(arpeggio((echo(((X+transpose(X,12) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,4,6) |transpose(((arpeggio(echo(X,4,6) ) +transpose(X,4) ) +transpose(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ,7) ) ,4) ) ) ,12) ,4) ) +transpose(((((transpose(shuffle(shuffle(X) ) ,-5) +transpose((X|transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) ,4) ) +transpose(echo(X,4,6) ,7) ) +arpeggio(transpose(transpose(X,-5) ,-5) ) ) +transpose((((X+transpose(transpose(echo(X,4,6) ,-7) ,4) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) |X) ,7) ) +shuffle(shuffle((X+transpose(X,12) ) ) ) ) ,4) ) ,7) ) +transpose((step(X,12) |X) ,4) ) ,4,6) +transpose((arpeggio(shuffle(transpose(echo(transpose(arpeggio(transpose(X,4) ) ,4) ,4,6) ,-5) ) ) +((arpeggio(arpeggio(((((echo((transpose((X+((X+transpose(X,4) ) +transpose(X,7) ) ) ,4) |transpose((X+X) ,-7) ) ,4,6) +transpose(step(step(transpose((X+transpose(X,7) ) ,-7) ,12) ,12) ,4) ) +transpose(transpose((transpose(echo(X,4,6) ,-7) +transpose(transpose((X|X) ,-5) ,7) ) ,4) ,7) ) +transpose((((arpeggio((X+transpose(X,12) ) ) +transpose(shuffle(shuffle(X) ) ,4) ) +transpose(shuffle(transpose(X,4) ) ,7) ) +transpose((arpeggio(transpose(X,4) ) |((X+X) +transpose(X,7) ) ) ,12) ) ,4) ) +transpose((transpose(((shuffle((X|(transpose(X,-5) +transpose(X,7) ) ) ) +transpose((transpose(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ,-7) +transpose(shuffle(step(X,12) ) ,7) ) ,4) ) +transpose((((step(X,12) +transpose(X,4) ) +transpose(transpose(X,-5) ,7) ) |X) ,7) ) ,4) +((X+X) +transpose(transpose(arpeggio((X+transpose(X,7) ) ) ,-5) ,12) ) ) ,7) ) ) ) +transpose(transpose((step((shuffle(arpeggio(((((X+transpose(X,4) ) +transpose((X+transpose(X,7) ) ,7) ) +transpose(X,4) ) +transpose(step((X+X) ,12) ,7) ) ) ) +transpose((arpeggio(transpose((arpeggio(X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,-7) ) +transpose(step(((shuffle(X) |X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ,12) ,4) ) ,7) ) ,12) +(((((step((arpeggio(X) +transpose((X+X) ,7) ) ,12) +transpose(step((((X+transpose(X,4) ) +transpose(X,7) ) |X) ,12) ,12) ) +transpose(((arpeggio(transpose((X|(X+X) ) ,4) ) +transpose((echo(arpeggio((X+transpose(X,7) ) ) ,4,6) |arpeggio(step(X,12) ) ) ,4) ) +transpose(echo(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose(transpose(X,4) ,7) ) ,4,6) ,7) ) ,4) ) +transpose(shuffle((echo(X,4,6) +transpose(step((X|X) ,12) ,4) ) ) ,7) ) +transpose(((((X|X) |(arpeggio(echo(X,4,6) ) +((X+transpose(X,4) ) +transpose((X+X) ,7) ) ) ) +transpose(transpose(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-5) ,-7) ,4) ) +transpose(echo(((X+transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(X,7) ) ,4,6) ,7) ) ,7) ) |echo(shuffle(step(((echo(X,4,6) +transpose(echo(X,4,6) ,4) ) +transpose(shuffle(X) ,7) ) ,12) ) ,4,6) ) ) ,-5) ,4) ) +transpose(transpose(shuffle(echo(arpeggio(((shuffle(step((((X+transpose(echo(X,4,6) ,4) ) +transpose((X+transpose(X,7) ) ,7) ) |(((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,-5) ) ) ,12) ) +transpose(echo(arpeggio(X) ,4,6) ,4) ) +transpose(echo((echo((X+transpose(X,12) ) ,4,6) +echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ) ,4,6) ,7) ) ) ,4,6) ) ,4) ,7) ) ) ,7) ) ,4,6) ,4)
random seed used was 1

NOTE: Generated phrase was too large ( 6785 ) , it has been truncated at 5000 notes. EXPR = arpeggio(transpose(step(arpeggio(arpeggio(step(transpose(arpeggio(shuffle((arpeggio(((X+transpose(X,4) ) +transpose(X,7) ) ) +transpose(shuffle(X) ,7) ) ) ) ,4) ,12) ) ) ,12) ,-7) )
random seed used was 0 EXPR = echo(((((transpose(echo(shuffle((step((step((((((((((transpose((X+transpose(X,12) ) ,-7) +transpose(step(transpose(X,-5) ,12) ,4) ) +transpose(echo(step(X,12) ,4,6) ,7) ) +echo(X,4,6) ) +transpose(shuffle((transpose(step(X,12) ,-5) |transpose(arpeggio(step(X,12) ) ,-5) ) ) ,4) ) +transpose(shuffle(transpose((((transpose(X,-5) +X) +transpose(X,4) ) +transpose((echo(X,4,6) +transpose((X+X) ,12) ) ,7) ) ,-5) ) ,7) ) +transpose(arpeggio(echo((transpose(X,-5) +transpose(X,7) ) ,4,6) ) ,4) ) +transpose(echo(echo(step(echo(((X+X) +(X+X) ) ,4,6) ,12) ,4,6) ,4,6) ,7) ) +transpose(echo(transpose(transpose(step(((X+transpose(X,4) ) +transpose(transpose(step(X,12) ,-5) ,7) ) ,12) ,-7) ,-7) ,4,6) ,4) ) +transpose(step(step(echo(shuffle(transpose((X+transpose(transpose(X,-7) ,12) ) ,-5) ) ,4,6) ,12) ,12) ,7) ) ,12) +transpose((transpose(step(transpose(X,-7) ,12) ,-7) |step(transpose((X+transpose(X,7) ) ,-7) ,12) ) ,7) ) ,12) +transpose(step(echo((transpose(X,4) +transpose(X,4) ) ,4,6) ,12) ,12) ) ) ,4,6) ,-5) +transpose(arpeggio(transpose((echo(arpeggio(transpose((X+transpose(X,7) ) ,4) ) ,4,6) +(transpose(shuffle(((((arpeggio(X) +transpose(X,4) ) +transpose(((echo(X,4,6) +transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,7) ) +transpose((transpose(X,-7) +transpose(((X+transpose(X,12) ) |X) ,12) ) ,4) ) +transpose((step((X+transpose(X,12) ) ,12) |X) ,7) ) ) ,4) +transpose(shuffle(shuffle(transpose((X|X) ,4) ) ) ,-5) ) ) ,-7) ) ,4) ) +transpose(step(transpose(transpose(echo(transpose(transpose(transpose(((echo(echo(((X+transpose(X,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,4,6) ,4,6) +transpose(((arpeggio(shuffle(shuffle(X) ) ) +transpose((transpose(shuffle((X+X) ) ,4) +transpose(X,-5) ) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,4) ) +transpose(((step((X|step(X,12) ) ,12) +transpose(transpose(transpose(((transpose(X,-5) |transpose(X,4) ) +transpose(X,4) ) ,-5) ,-7) ,4) ) +transpose(transpose((X+transpose(X,7) ) ,-5) ,7) ) ,7) ) ,-7) ,-5) ,-5) ,4,6) ,4) ,4) ,12) ,7) ) +transpose((shuffle((transpose(shuffle((step(X,12) +transpose(shuffle(transpose(shuffle(X) ,4) ) ,7) ) ) ,-7) |transpose((((step(shuffle((arpeggio(X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,12) ) ) ,12) +transpose(((transpose(transpose(X,4) ,-7) +echo(((transpose(transpose(X,-7) ,-7) +transpose(transpose((X+transpose(X,12) ) ,-5) ,4) ) +transpose(step(arpeggio(X) ,12) ,7) ) ,4,6) ) |echo((X|((X+transpose(X,4) ) +transpose(X,7) ) ) ,4,6) ) ,4) ) +transpose(step(((transpose(X,4) +transpose(echo((X+X) ,4,6) ,4) ) +transpose(shuffle(X) ,7) ) ,12) ,7) ) +shuffle(((arpeggio(shuffle(X) ) +transpose(arpeggio(transpose(X,-5) ) ,4) ) +transpose(transpose((shuffle(X) +transpose((echo(X,4,6) |(X|X) ) ,12) ) ,-5) ,7) ) ) ) ,-5) ) ) |transpose((transpose(step(((arpeggio(((step(shuffle(X) ,12) +transpose(((step(transpose((X+X) ,4) ,12) +transpose(echo(transpose(X,4) ,4,6) ,4) ) +transpose(transpose(X,4) ,7) ) ,12) ) +(transpose(echo(X,4,6) ,-7) +(((X+transpose(arpeggio(X) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) +transpose(transpose(echo(X,4,6) ,-7) ,7) ) ) ) ) +transpose(transpose(step(echo(arpeggio(arpeggio(arpeggio((X+transpose(X,7) ) ) ) ) ,4,6) ,12) ,-5) ,4) ) +transpose((transpose(echo(transpose(transpose(X,-5) ,4) ,4,6) ,-7) +transpose(shuffle((transpose(shuffle(X) ,-7) +echo(X,4,6) ) ) ,7) ) ,7) ) ,12) ,-5) |step(((arpeggio(echo(((transpose(transpose(X,-7) ,-5) +transpose(transpose((arpeggio(step(X,12) ) |step(echo(X,4,6) ,12) ) ,-5) ,4) ) +transpose(transpose(X,-7) ,7) ) ,4,6) ) +transpose((transpose((transpose((((transpose((X|X) ,4) +transpose((X+transpose(X,12) ) ,4) ) +transpose((X+((X+transpose(X,4) ) +transpose(X,7) ) ) ,7) ) |transpose(((echo(X,4,6) +transpose(X,4) ) +transpose(transpose(X,4) ,7) ) ,4) ) ,4) +((arpeggio(((transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,-7) +transpose(X,4) ) +transpose((X+X) ,7) ) ) +transpose(arpeggio((((X+X) +transpose(X,4) ) +transpose(step(X,12) ,7) ) ) ,4) ) +transpose(((transpose(((transpose(X,4) +transpose(X,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,-5) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) |(X+X) ) +((X|X) |X) ) ,4) ) +transpose(step(((X+transpose((X|X) ,4) ) +transpose(transpose(X,-5) ,7) ) ,12) ,7) ) ,7) ) ) ,-7) +transpose(shuffle((((shuffle((echo(transpose(X,4) ,4,6) +echo(X,4,6) ) ) +transpose((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(shuffle(X) ,-5) ) ,12) ) +transpose(((((shuffle(X) +X) +((X+transpose(X,7) ) +X) ) +transpose(shuffle(arpeggio((X+transpose(X,12) ) ) ) ,4) ) +transpose(transpose((X|X) ,4) ,7) ) ,4) ) +transpose((transpose(step((X+X) ,12) ,-7) +transpose(transpose(transpose(step(transpose(X,4) ,12) ,4) ,-5) ,12) ) ,7) ) ) ,7) ) ,4) ) +transpose(transpose(shuffle(X) ,-7) ,7) ) ,12) ) ,-7) ) ,4) ) +transpose((shuffle(shuffle(transpose(transpose(((echo((((shuffle(X) +transpose(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,7) ) +transpose((X|X) ,12) ) ,4) ) +transpose(step(step(X,12) ,12) ,7) ) +transpose(step(shuffle(transpose(X,4) ) ,12) ,7) ) ,4,6) +transpose(echo(echo(((transpose(((X+X) +transpose(step(echo(X,4,6) ,12) ,7) ) ,-7) +transpose(echo((shuffle(X) |((X|X) |(X+transpose(X,12) ) ) ) ,4,6) ,12) ) +transpose(shuffle(transpose(arpeggio((X|((X+transpose(X,4) ) +transpose(X,7) ) ) ) ,-5) ) ,7) ) ,4,6) ,4,6) ,4) ) +transpose(step(shuffle(transpose(echo(X,4,6) ,4) ) ,12) ,7) ) ,-7) ,-7) ) ) |transpose(shuffle(step(echo(((transpose(shuffle((transpose((step(shuffle(X) ,12) |shuffle(((X+transpose(arpeggio(X) ,4) ) +transpose((X|X) ,7) ) ) ) ,-5) +(arpeggio(transpose((((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(X,4) ) +transpose(X,7) ) +arpeggio(X) ) ,-5) ) +transpose(step(arpeggio((X|X) ) ,12) ,4) ) ) ) ,4) +transpose(((((transpose((transpose((arpeggio(transpose(X,-7) ) +transpose(arpeggio(arpeggio(X) ) ,12) ) ,4) |((X+shuffle(X) ) +step(echo(X,4,6) ,12) ) ) ,4) +transpose((step(((transpose(echo(shuffle(X) ,4,6) ,-7) +transpose(arpeggio((arpeggio(X) |(X|shuffle(X) ) ) ) ,4) ) +transpose(((arpeggio(((X|X) +echo(X,4,6) ) ) +transpose(transpose(((echo(X,4,6) +transpose(X,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,-5) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) ,7) ) ,12) |(echo(echo((X+transpose(X,7) ) ,4,6) ,4,6) +((transpose(transpose(arpeggio(X) ,-5) ,-7) +transpose(transpose((X|X) ,4) ,4) ) +transpose(arpeggio(arpeggio(echo(X,4,6) ) ) ,7) ) ) ) ,12) ) +transpose((step(step(transpose(transpose(X,-5) ,-5) ,12) ,12) +(transpose(X,4) +(echo((X|X) ,4,6) +transpose(transpose((X+X) ,4) ,12) ) ) ) ,4) ) +transpose(step(transpose((shuffle(((step(X,12) +transpose(transpose(X,4) ,12) ) |transpose((X+X) ,-5) ) ) +transpose((transpose(echo(((X+transpose(X,4) ) +transpose(transpose(X,4) ,7) ) ,4,6) ,-5) +transpose(echo(shuffle(X) ,4,6) ,7) ) ,12) ) ,-5) ,12) ,7) ) +transpose((((step(echo(((X|X) +transpose((X+X) ,12) ) ,4,6) ,12) +transpose((transpose(echo(X,4,6) ,-5) +transpose(((arpeggio(((X+transpose(shuffle(transpose(X,4) ) ,4) ) +transpose(step(X,12) ,7) ) ) +transpose((X|X) ,4) ) +transpose(echo(X,4,6) ,7) ) ,7) ) ,4) ) +transpose((transpose(transpose(X,-5) ,-7) +(transpose(shuffle(X) ,-5) +transpose(((shuffle(echo(X,4,6) ) +transpose(((X+transpose(X,12) ) |step(X,12) ) ,4) ) +transpose((shuffle(X) +transpose(X,12) ) ,7) ) ,12) ) ) ,7) ) +transpose(echo(echo(transpose((((X+transpose(X,7) ) +transpose(X,4) ) +transpose(X,7) ) ,-5) ,4,6) ,4,6) ,12) ) ,7) ) ,4) ) +transpose((step(echo(echo(step((((X+transpose(X,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) |transpose(step(X,12) ,-7) ) ,12) ,4,6) ,4,6) ,12) +echo(((((transpose((echo(X,4,6) +((X+transpose(X,4) ) +transpose(X,7) ) ) ,4) +(X+transpose(arpeggio(X) ,-7) ) ) +transpose(arpeggio(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) ,7) ) +transpose(transpose(shuffle(shuffle(shuffle((X+transpose(X,12) ) ) ) ) ,-5) ,4) ) +transpose((echo(step(shuffle(echo(((X+transpose(X,4) ) +transpose(X,7) ) ,4,6) ) ,12) ,4,6) +step(arpeggio(transpose((X|X) ,4) ) ,12) ) ,7) ) ,4,6) ) ,7) ) ,4,6) ,12) ) ,4) ) ,7) ) ,4,6)
random seed used was 0

NOTE: Generated phrase was too large ( 46300 ) , it has been truncated at 5000 notes. EXPR = arpeggio((transpose((step(((((((((shuffle(shuffle((X+transpose(X,7) ) ) ) +transpose((transpose(shuffle(X) ,-7) +transpose(step(X,12) ,7) ) ,12) ) +transpose(echo(transpose(X,-5) ,4,6) ,12) ) +transpose(transpose(transpose(((X+transpose(transpose(X,4) ,4) ) +transpose(X,7) ) ,-5) ,4) ,4) ) +transpose(arpeggio(arpeggio(transpose(X,4) ) ) ,7) ) +transpose(echo(echo((((step(X,12) +transpose(transpose(X,-7) ,7) ) +transpose(step(X,12) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,4,6) ,4,6) ,4) ) +transpose(step(transpose(step((X+transpose(X,12) ) ,12) ,-7) ,12) ,7) ) +transpose(shuffle(((echo(((arpeggio(X) +transpose((X+X) ,4) ) +transpose(transpose(X,-5) ,7) ) ,4,6) +transpose(arpeggio(X) ,7) ) |(transpose(step(step(echo(X,4,6) ,12) ,12) ,-5) +transpose(transpose((arpeggio(X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ,-5) ,12) ) ) ) ,7) ) +transpose(((step(arpeggio((transpose(transpose(X,4) ,-7) +transpose(echo(X,4,6) ,4) ) ) ,12) +transpose(echo((X+transpose(step(X,12) ,12) ) ,4,6) ,4) ) +transpose(transpose(transpose((transpose((X|echo(X,4,6) ) ,-5) +transpose(step(X,12) ,4) ) ,4) ,-5) ,7) ) ,12) ) ,12) |transpose(echo(shuffle(transpose(transpose(transpose((X|X) ,-5) ,4) ,-5) ) ,4,6) ,-5) ) ,-7) |((arpeggio(((step(transpose((echo((((arpeggio(shuffle(arpeggio(X) ) ) +transpose(shuffle(transpose(transpose(X,-5) ,-7) ) ,4) ) +transpose((X+transpose(X,12) ) ,7) ) |((X|shuffle(X) ) +echo(X,4,6) ) ) ,4,6) +transpose(transpose(transpose(shuffle(step(transpose(X,-5) ,12) ) ,4) ,-7) ,-7) ) ,-7) ,12) +transpose((echo((((echo((shuffle((X+transpose(X,12) ) ) +transpose(arpeggio(X) ,7) ) ,4,6) +transpose(transpose(shuffle(transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) ,-7) ,4) ) +transpose((((X+transpose(X,12) ) +X) |step((X+transpose(X,12) ) ,12) ) ,7) ) +transpose((((transpose((X+transpose((X+transpose(X,12) ) ,12) ) ,-7) +transpose(transpose((X+((X+transpose(transpose(X,-7) ,4) ) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,7) ) ) ,4) ,7) ) +((echo(echo(X,4,6) ,4,6) |transpose(X,-5) ) +transpose((X+transpose(X,12) ) ,7) ) ) |(shuffle(shuffle((arpeggio(shuffle(X) ) |echo((arpeggio(X) |X) ,4,6) ) ) ) +(arpeggio((((shuffle(X) +transpose(((X+transpose(X,4) ) +transpose(X,7) ) ,4) ) +transpose(transpose(X,4) ,7) ) +X) ) |((X+transpose(X,4) ) +transpose(X,7) ) ) ) ) ,7) ) ,4,6) +transpose(echo(arpeggio(arpeggio(echo((arpeggio((X+transpose(X,7) ) ) |echo(X,4,6) ) ,4,6) ) ) ,4,6) ,7) ) ,4) ) +transpose(arpeggio(transpose(step(((step(X,12) +((transpose(echo((X|X) ,4,6) ,-7) +transpose((echo(X,4,6) +step(X,12) ) ,4) ) +transpose(((X+transpose(X,12) ) +(X+X) ) ,7) ) ) +transpose((echo(X,4,6) +transpose(X,12) ) ,4) ) ,12) ,-7) ) ,7) ) ) +transpose(((transpose(echo(transpose(echo(shuffle(((((transpose(shuffle(arpeggio(echo(X,4,6) ) ) ,-5) +transpose((step(X,12) +transpose(transpose(step(transpose(X,4) ,12) ,-5) ,12) ) ,4) ) +transpose(arpeggio((X+shuffle(X) ) ) ,7) ) +transpose(shuffle(transpose(((X+transpose(echo(X,4,6) ,7) ) +(step(X,12) |(shuffle(X) |(X+transpose(X,7) ) ) ) ) ,-5) ) ,4) ) +transpose(shuffle((echo(step((X+X) ,12) ,4,6) |transpose((X|X) ,-7) ) ) ,7) ) ) ,4,6) ,-5) ,4,6) ,-5) +transpose(echo(shuffle(step(arpeggio((transpose(transpose(((echo(((echo(X,4,6) +transpose((X+transpose(X,12) ) ,4) ) +transpose(X,7) ) ,4,6) +transpose(shuffle((X+transpose(echo(X,4,6) ,12) ) ) ,4) ) +transpose((shuffle(X) |((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(transpose(X,-7) ,4) ) +transpose((X+X) ,7) ) ) ,7) ) ,-5) ,-5) |transpose((transpose(arpeggio(shuffle(transpose(X,-5) ) ) ,-5) +echo((transpose(arpeggio(X) ,-5) +transpose((X+transpose(X,12) ) ,7) ) ,4,6) ) ,-5) ) ) ,12) ) ,4,6) ,4) ) +transpose((transpose(transpose(echo(transpose(echo(((arpeggio((arpeggio(X) +transpose(((X+X) +X) ,7) ) ) +transpose(arpeggio(arpeggio(echo(X,4,6) ) ) ,4) ) +transpose(transpose((arpeggio(X) |echo(X,4,6) ) ,-7) ,7) ) ,4,6) ,4) ,4,6) ,-5) ,-7) +transpose(shuffle(transpose((transpose(transpose((((shuffle((X+transpose(X,7) ) ) +transpose(transpose(X,-7) ,4) ) +transpose(shuffle(transpose(X,-5) ) ,7) ) +transpose(shuffle(X) ,12) ) ,4) ,-7) +transpose((arpeggio(transpose(shuffle(arpeggio(X) ) ,-5) ) |(step(X,12) |(X+transpose(X,12) ) ) ) ,7) ) ,-7) ) ,7) ) ,7) ) ,4) ) +transpose(shuffle(transpose(transpose(((step((step(X,12) +transpose(transpose(transpose(arpeggio(((((X+transpose(X,4) ) +transpose(X,7) ) +transpose(echo(X,4,6) ,4) ) +transpose(shuffle(X) ,7) ) ) ,4) ,-5) ,7) ) ,12) +transpose(step(transpose(X,-7) ,12) ,4) ) +transpose(((transpose(step((((X+X) +transpose(step(X,12) ,4) ) +transpose(X,7) ) ,12) ,4) +transpose(((transpose(echo((transpose(X,-7) +transpose(echo(X,4,6) ,7) ) ,4,6) ,-7) +transpose((shuffle(X) +transpose(step(transpose(transpose(X,4) ,-5) ,12) ,12) ) ,4) ) +transpose(echo(shuffle(((X|(X+X) ) |echo(X,4,6) ) ) ,4,6) ,7) ) ,4) ) +transpose(transpose(transpose((transpose(echo(X,4,6) ,-5) +transpose(arpeggio(transpose(X,-7) ) ,12) ) ,4) ,-7) ,7) ) ,7) ) ,-7) ,-7) ) ,7) ) ) )
random seed used was 0


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