Tips for golfing in Pip
Use preinitialized variables
Pip has many global variables that are pre-initialized so you can avoid manually writing a number/string/something else out yourself.
Here are some of them (complete list):

_ Identity function (== {a})

h 100

i 0

k &quot;, &quot;

l Empty list

m 1000 (mnemonic: Roman numeral M)

n Newline character

o 1

s Space character

t 10

v -1

w Matches whitespace \s+

x Empty string

z Lowercase alphabet a to z

B Block that returns its second argument ({b})

G Block that returns its argument list ({g})

AZ Uppercase alphabet A to Z

CZ Lowercase consonants b to z

PA All Printable ASCII characters, 32 through 126

PI \$\pi\$ (3.141592653589793)

VW Lowercase vowels a to u

VY Lowercase vowels a to y

XA Matches one Latin letter [A-Za-z] (there are more X* commands)


Link to documentation