The lua interpreter packages do not set native search paths, so they cannot find lua modules.
$ guix environment --ad-hoc lua lua-lpeg $ lua > require('lpeg') … ERROR … However: $ guix environment --ad-hoc lua lua-lpeg $ export LUA_PATH="$GUIX_ENVIRONMENT/share/lua/5.3/?.lua;$GUIX_ENVIRONMENT/share/lua/5.3/?/?.lua" $ export LUA_CPATH="$GUIX_ENVIRONMENT/lib/lua/5.3/?.so;$GUIX_ENVIRONMENT/lib/lua/5.3/?/?.so" $ lua > require('lpeg') table: 0x1b80300 -- Ricardo GPG: BCA6 89B6 3655 3801 C3C6 2150 197A 5888 235F ACAC http://elephly.net