al-quran.reflectslight.io/bin/check-dependencies

#!/bin/sh

find_dep() {
    dep=$1
    which $dep > /dev/null 2>&1
    if [ $? -eq 0 ]; then
        echo found: $dep
    else
        echo error: $dep is required, but not installed
    fi
}

find_dep ruby
find_dep bundle
find_dep node
find_dep npm
find_dep nginx
find_dep doas