concrete

#!/bin/bash
FILE=Rockfile
WALL=$(printf "%s/.wall" $(pwd))
TEMP=$(printf "%s/.tmp" $(pwd))

function rock_git() {
    mkdir -p $TEMP
    DIR=$(basename $1 .git)
    pushd $TEMP
    git clone $1
    pushd $DIR
    if [ -n "$2" ]; then
        git checkout $2
    else
	git checkout master
    fi
    SPEC=$(ls *.rockspec | sort | tail -n 1)
    luarocks --tree=$WALL make $SPEC
    popd
    popd
}

function rock() {
    if [ $1 == 'git' ]; then
	rock_git $2 $3
    else
	luarocks --tree=$WALL install $1 $2
    fi
}
. $FILE

Rockfile

rock https://raw.github.com/Neopallium/lua-pb/master/lua-pb-scm-0.rockspec
rock git https://github.com/bakins/lua-resty-riak refactor