sbt - How to parallellize tasks given on the command line -

i'd able execute dynamically tasks in sbt.

so, i'm using command line:

sbt taska taskb taskc 

it works ok, of them executed sequentially.

on other hand, if programmatically write inside build.sbt:

val alltasks = taskkey[unit]("all") alltasks := {   taska.value   taskb.value   taskc.value } 

all of them executed in parallel.

how can behavior on command line?

you can use all command:

build.sbt

taskkey[string]("taska") := { println("a start"); thread.sleep(3000); println("a end"); "a" } taskkey[string]("taskb") := { println("b start"); thread.sleep(2000); println("b end"); "b" } taskkey[string]("taskc") := { println("c start"); thread.sleep(1000); println("c end"); "c" } 

and running it:

> taska taskb taskc c start start b start c end b end end