$ nix eval cachix.meta.outputsToInstall -f .
[ "bin" ]

$ du -shc $(nix-store -qR $(nix eval --raw cachix.bin.outPath -f .))
29M     /nix/store/bjmg1g133m9xwxa0iy5inp2snvnfg151-glibc-2.27
12M     /nix/store/397caphb7dl7i20amsm105a654y52s2z-ncurses-6.1-20190112
68K     /nix/store/d5a6j2hs4x93fs1412qi0k50crvvc45y-libffi-3.2.1
140K    /nix/store/kn8zwvcvqbz1bncm84nkmz1s9wxz46wi-zlib-1.2.11
352K    /nix/store/s2fy0ks3w2mn4c01lxvj4c188rf3d08s-xz-5.2.4
5.7M    /nix/store/9yb1sriwirgm68dhz1h6jw7x3ar5z49g-gcc-7.4.0-lib
704K    /nix/store/xhanrizisc0ljrrvrgy5qcrdrh83sysg-gmp-6.1.2
9.7M    /nix/store/67md18y1c20c8g2sl41nwl4fd6w0w4r0-cachix-0.2.1-bin
58M     total

$ nix-env -f . -iA cachix --store `pwd`/tmp                                                            
installing 'cachix-0.2.1'                                                                                         
these paths will be fetched (303.47 MiB download, 3603.11 MiB unpacked):