# thanks: https://muffinresearch.co.uk/showing-last-two-directories-of-pwd-in-bash-prompt/

function PWD {
  pwd | sed 's/^\/Users\/<YOUR_USERNAME>/~/' | awk -F\/ '{print $(NF-1),$(NF)}' | sed 's/ /\//' | sed 's/~\/~/~/'
}

export PS1="\u\[\e[m\]:\[\e[36m\]\$(PWD)\[\e[m\] "

# backslash before $ tells it to run the function each time; 
# else it is only run once and won't update as you switch directories