open Elpe
open Lwt.Syntax
let _ =
  let deriv =
    object (self)
      inherit derivation
      method name = "cowsay-shell"
      method! setup =
        print_endline "Starting setup"; 
        let* package = (ubuntu "cowsay")#build in
        let outdir = (List.hd package.destdir) in
        let change_path = "export PATH=$PATH:" ^ outdir ^ "/usr/games/" in
        let change_cowpath = "export COWPATH=" ^ outdir ^ "/usr/share/cowsay/cows/" in
        Lwt.return (change_path ^ "\n" ^ change_cowpath)
    end
  in build deriv