#!/usr/bin/env nix-shell
#!nix-shell -i bash -p bash -p nix

# script to reclaim some hard drive space
# some of this is documented here:
# - <https://nixos.wiki/wiki/Storage_optimization>

if [ "$(id -u)" -ne 0 ]; then
  echo 'must be run as root!'
fi

set -xeu

# scan the store and hard-link identical files
# nix-store --optimise

nix-collect-garbage --delete-older-than 30d

set +x

echo 'to free more space (e.g. boot space), manually manage the profiles'
echo '- nix-env --profile /nix/var/nix/profiles/system --list-generations'
echo '- nix-env --profile /nix/var/nix/profiles/system --delete-generations {first..last}'
echo '- sudo sane-reclaim-boot-space`