-q to quote the input

[nkh]

in command: piper --global hi blue '\d+' red

'\d' needs to be quadruple quote as in this example:
time seq 20 | rust-parallel 'echo {} | piper --global hi blue '\\d+' red'

FYI, gnu parallel needed the \ to be doubled or -q option to be used

[mmstick]

Quoting has been added to version 0.6.1