nix-support.sh

# prepare nix files on "nix" branch
git checkout -b nix

# tuck everything except shell.nix under a nix/ directory
mkdir -p nix

# generate nix expressions for dependencies
nix-shell --packages bundler --run 'bundle lock'
nix-shell --packages bundix --run 'bundix --gemset=nix/gemset.nix'

# pin nixpkgs
cat > nix/nixpkgs.nix <<EOF
import (builtins.fetchTarball {
  url = "https://github.com/NixOS/nixpkgs/archive/be1461fc0ab29c45c69e7b2c2097c887750e4fe0.tar.gz";
  sha256 = "1fdlnfipa3qpyzqqqy3cf5zicgj6chwmd40yz8n60nil8qi6452w";
})
EOF

# write shell.nix
vim shell.nix

# write an init script that can bootstrap nix support in a fresh repo
vim nix/init.sh

# commit with bootstrap instructions
git add shell.nix nix/
git commit -m 'initial nix support

To initialize nix support in a local repo, run:

  tmpDir=$(mktemp --tmpdir -d fakeproject-nix.XXXXXX)
  git clone --depth 1 --branch nix \
      git@github.com:ivanbrennan/fakeproject.git $tmpDir
  $tmpDir/nix/init.sh
  rm -rf $tmpDir && unset tmpDir
'